Merge branch 'master' into pr/3675

.eslintrc.yml

@@ -5,6 +5,7 @@ plugins:
   - babel
   - react
   - prettier
+  - json
 
 extends:
   - prettier

.github/CONTRIBUTING.md

@@ -28,7 +28,7 @@ time as the team learns, listens and refines how we work with the community.
 
 ### Code of Conduct
 
-This project adheres to the Contributor Covenant [code of conduct](CODE_OF_CONDUCT.md).
+This project adheres to the Contributor Covenant [code of conduct](../CODE_OF_CONDUCT.md).
 By participating, you are expected to uphold this code.
 Please report unacceptable behavior to [opensource+desktop@github.com](mailto:opensource+desktop@github.com).
 
@@ -58,7 +58,7 @@ reports :mag_right:.
 Before creating bug reports, please check [this list](#before-submitting-a-bug-report)
 as you might find out that you don't need to create one. When you are creating
 a bug report, please [include as many details as possible](#how-do-i-submit-a-good-bug-report).
-Fill out [the required template](./.github/ISSUE_TEMPLATE.md), the information
+Fill out [the required template](ISSUE_TEMPLATE.md), the information
 it asks for helps us resolve issues faster.
 
 #### Before Submitting A Bug Report
@@ -73,7 +73,7 @@ comment to the existing issue if there is extra information you can contribute.
 Bugs are tracked as [GitHub issues](https://guides.github.com/features/issues/).
 
 Simply create an issue on the [GitHub Desktop issue tracker](https://github.com/desktop/desktop/issues)
-and fill out the provided [issue template](./.github/ISSUE_TEMPLATE.md).
+and fill out the provided [issue template](ISSUE_TEMPLATE.md).
 
 The information we are interested in includes:
 
@@ -93,7 +93,7 @@ community understand your suggestion :pencil: and find related suggestions
 Before creating enhancement suggestions, please check [this list](#before-submitting-an-enhancement-suggestion)
 as you might find out that you don't need to create one. When you are creating
 an enhancement suggestion, please [include as many details as possible](#how-do-i-submit-a-good-enhancement-suggestion).
-Fill in [the template](./.github/ISSUE_TEMPLATE.md), including the steps
+Fill in [the template](ISSUE_TEMPLATE.md), including the steps
 that you imagine you would take if the feature you're requesting existed.
 
 #### Before Submitting An Enhancement Suggestion
@@ -151,7 +151,7 @@ pull requests.
 | `enhancement` | [search](https://github.com/desktop/desktop/labels/enhancement) | Feature requests. |
 | `bug` | [search](https://github.com/desktop/desktop/labels/bug)  | Confirmed bugs or reports that are very likely to be bugs. |
 | `more-information-needed` | [search](https://github.com/desktop/desktop/labels/more-information-needed) | More information needs to be collected about these problems or feature requests (e.g. steps to reproduce). |
-| `needs-reproduction` | [search](https://github.com/desktop/desktop/labels/needs-reproduction)  | Likely bugs, but haven't been reliably reproduced. |
+| `reviewer-needs-to-reproduce` | [search](https://github.com/desktop/desktop/labels/reviewer-needs-to-reproduce)  | Likely bugs, but haven't been reliably reproduced by a reviewer. |
 | `stale` | [search](https://github.com/desktop/desktop/labels/stale) | Issues that are inactive and marked to be closed. |
 | `macOS` | [search](https://github.com/desktop/desktop/labels/macOS)  | Issues specific to macOS users. |
 | `Windows` | [search](https://github.com/desktop/desktop/labels/Windows)  | Issues specific to Windows users. |
@@ -170,4 +170,5 @@ pull requests.
 
 | Label name | :mag_right: | Description |
 | --- | --- | --- |
+| `infrastructure` | [search](https://github.com/desktop/desktop/labels/infrastructure) | Pull requests not related to the core application - documentation, dependencies, tooling, etc. |
 | `ready-for-review` | [search](https://github.com/desktop/desktop/labels/ready-for-review)  | Pull Requests that are ready to be reviewed by the maintainers. |

.github/ISSUE_TEMPLATE.md

@@ -1,89 +1,65 @@
 <!--
+First and foremost, we’d like to thank you for taking the time to contribute to our project. Before submitting your issue, please follow these steps:
 
-Please summarize the issue in the title, and then use the template below to
-fill out the details so we can reproduce the issue on our end.
-
+1. Familiarize yourself with our contributing guide:
+	* https://github.com/desktop/desktop/blob/master/CONTRIBUTING.md#contributing-to-github-desktop
+2. Check if your issue (and sometimes workaround) is in the known-issues doc:
+	* https://github.com/desktop/desktop/blob/master/docs/known-issues.md
+3. Make sure your issue isn’t a duplicate of another issue
+4. If you have made it to this step, go ahead and fill out the template below
 -->
 
-### Description
-
-[Description of the issue]
-
-### Version
-
+## Description
 <!--
-
-What version of GitHub Desktop are you running? This is displayed under the
-`About GitHub Desktop` menu item. If you are running from source, include
-the commit by running `git rev-parse HEAD` from your local repository.
-
+Provide a detailed description of the behavior you're seeing or the behavior you'd like to see **below** this comment.
 -->
 
-**GitHub Desktop version:** [version here]
 
+## Version
 <!--
+Place the version of GitHub Desktop you have installed **below** this comment. This is displayed under the 'About GitHub Desktop' menu item. If you are running from source, include the commit by running `git rev-parse HEAD` from the local repository.
+-->
+* GitHub Desktop:
+<!--
+Place the version of your operating system **below** this comment. The operating system you are running on may also help with reproducing the issue. If you are on macOS, launch 'About This Mac' and write down the OS version listed. If you are on Windows, open 'Command Prompt' and attach the output of this command: 'cmd /c ver'
+-->
+* Operating system:
 
-The operating system you are running on may also help with reproducing the
-issue:
-
- - If you are on macOS, launch `About This Mac` and write down the OS version
-   listed.
- - If you are on Windows, open `Command Prompt` and attach the output of this
-   command: `cmd /c ver`
 
+## Steps to Reproduce
+<!--
+List the steps to reproduce your issue **below** this comment
+ex,
+1. `step 1`
+2. `step 2`
+3. `and so on…`
 -->
 
-**OS version:** [version here]
+### Expected Behavior
+<!-- What you expected to happen -->
 
-### Steps to Reproduce
+### Actual Behavior
+<!-- What actually happens -->
 
-1. [First step]
-1. [Second step]
-1. [and so on]
 
+## Additional Information
 <!--
+Place any additional information, configuration, or data that might be necessary to reproduce the issue **below** this comment.
 
-If the issue involves a specific public repository, including the information
-about that repository will make it is easier to recreate the issue.
+If you have screen shots or gifs that demonstrate the issue, please include them.
 
-If you think screenshots or a GIF recording will help demonstrate the issue
-better, feel free to add them here.
+If the issue involves a specific public repository, including the information about it will make it easier to recreate the issue.
 
+If you are dealing with a performance issue or regression, attaching a Timeline profile of the task will help the developers understand the runtime behavior of the application on your machine.
+https://github.com/desktop/desktop/blob/master/docs/contributing/timeline-profile.md
 -->
 
-**Expected behavior:** [What you expected to happen]
-
-**Actual behavior:** [What actually happened]
-
-**Reproduces how often:** [What percentage of the time does it reproduce?]
-
 ### Logs
-
 <!--
+Attach your log file (You can simply drag your file here to insert it) to this issue. Please make sure the generated link to your log file is **below** this comment section otherwise it will not appear when you submit your issue.
 
-There may be some relevant information in log files generated by GitHub
-Desktop:
-
- - If you are on macOS, attach the most recent log file from:
-   `~/Library/Application Support/GitHub Desktop/logs/*.desktop.production.log`
- - If you are on Windows, attach the most recent log file from:
-   `%APPDATA%\GitHub Desktop\logs\*.desktop.production.log`
-
-The log files are organized by date, so see if anything was generated for
-today's date.
-
--->
-
-#### Additional Information
-
-<!--
-
-Any additional information, configuration or data that might be necessary to
-reproduce the issue.
-
-If you are dealing with a performance issue or regression, attaching a
-[Timeline profile](https://github.com/desktop/desktop/blob/master/docs/contributing/timeline-profile.md)
-of the task will help the developers understand the runtime behavior of the
-application on your machine.
+macOS logs location: `~/Library/Application Support/GitHub Desktop/logs/*.desktop.production.log`
+Windows logs location: `%APPDATA%\GitHub Desktop\logs\*.desktop.production.log`
 
+The log files are organized by date, so see if anything was generated for today's date.
 -->

.github/config.yml

@@ -2,12 +2,17 @@
 
 # *Required* Comment to reply with
 requestInfoReplyComment: >
-  We require the template to be filled out on all new issues. We do this so that we can be certain we have
-  all the information we need to address your submission efficiently. This allows the maintainers to spend
-  more time fixing bugs, implementing enhancements, and reviewing and merging pull requests.
+  Thanks for reaching out!
+
+  We require the [template](https://github.com/desktop/desktop/blob/master/.github/CONTRIBUTING.md#how-do-i-submit-a-good-bug-report) to be filled out with all new issues. We do this so that
+  we can be certain we have all the information we need to address your
+  submission efficiently. This allows the maintainers to spend more time fixing
+  bugs, implementing enhancements, and reviewing and merging pull requests.
+
+  Thanks for understanding and meeting us halfway 😀
 
 requestInfoLabelToAdd: more-information-needed
 
 requestInfoOn:
   pullRequest: false
-  issue: true
+  issue: true

.gitignore

@@ -7,4 +7,5 @@ app/node_modules/
 .DS_Store
 .awcache
 .idea/
+.vs/
 .eslintcache

.travis.yml

@@ -57,7 +57,7 @@ install:
   - yarn install --force
 
 script:
-  - yarn lint && yarn build:prod && yarn test:setup && yarn test
+  - yarn lint && yarn validate-changelog && yarn build:prod && yarn test:setup && yarn test
 
 after_failure:
   - yarn test:review

README.md

@@ -48,13 +48,16 @@ First, please search the [open issues](https://github.com/desktop/desktop/issues
 and [closed issues](https://github.com/desktop/desktop/issues?q=is%3Aclosed)
 to see if your issue hasn't already been reported (it may also be fixed).
 
+There is also a list of [known issues](https://github.com/desktop/desktop/blob/master/docs/known-issues.md)
+that are being tracked against Desktop, and some of these issues have workarounds.
+
 If you can't find an issue that matches what you're seeing, open a [new issue](https://github.com/desktop/desktop/issues/new)
 and fill out the template to provide us with enough information to investigate
 further.
 
 ## How can I contribute to GitHub Desktop?
 
-The [CONTRIBUTING.md](./CONTRIBUTING.md) document will help you get setup and
+The [CONTRIBUTING.md](./.github/CONTRIBUTING.md) document will help you get setup and
 familiar with the source. The [documentation](docs/) folder also contains more
 resources relevant to the project.
 

app/.npmrc

@@ -1,4 +1,4 @@
 runtime = electron
 disturl = https://atom.io/download/electron
-target = 1.7.11
+target = 1.8.3
 arch = x64

app/package.json

@@ -3,7 +3,7 @@
   "productName": "GitHub Desktop",
   "bundleID": "com.github.GitHubClient",
   "companyName": "GitHub, Inc.",
-  "version": "1.0.14-beta4",
+  "version": "1.1.2-beta1",
   "main": "./main.js",
   "repository": {
     "type": "git",
@@ -25,7 +25,7 @@
     "codemirror-mode-elixir": "1.1.1",
     "deep-equal": "^1.0.1",
     "dexie": "^2.0.0",
-    "dugite": "1.57.0",
+    "dugite": "1.61.0",
     "electron-window-state": "^4.0.2",
     "event-kit": "^2.0.0",
     "file-uri-to-path": "0.0.2",
@@ -37,11 +37,11 @@
     "moment": "^2.17.1",
     "mri": "^1.1.0",
     "primer-support": "^4.0.0",
-    "react": "^15.6.2",
+    "react": "^16.2.0",
     "react-addons-shallow-compare": "^15.6.2",
-    "react-dom": "^15.6.2",
+    "react-dom": "^16.2.0",
     "react-transition-group": "^1.2.0",
-    "react-virtualized": "^9.10.1",
+    "react-virtualized": "^9.18.5",
     "registry-js": "^1.0.7",
     "runas": "^3.1.1",
     "source-map-support": "^0.4.15",
@@ -58,9 +58,7 @@
   "devDependencies": {
     "devtron": "^1.4.0",
     "electron-debug": "^1.1.0",
-    "electron-devtools-installer": "^2.2.1",
-    "react-addons-perf": "15.4.2",
-    "react-addons-test-utils": "^15.6.2",
+    "electron-devtools-installer": "^2.2.3",
     "style-loader": "^0.13.2",
     "temp": "^0.8.3",
     "webpack-hot-middleware": "^2.10.0"

app/src/lib/app-state.ts

@@ -343,11 +343,11 @@ export interface IRepositoryState {
   readonly gitHubUsers: Map<string, IGitHubUser>
 
   /** The commits loaded, keyed by their full SHA. */
-  readonly commits: Map<string, Commit>
+  readonly commitLookup: Map<string, Commit>
 
   /**
    * The ordered local commit SHAs. The commits themselves can be looked up in
-   * `commits.`
+   * `commitLookup.`
    */
   readonly localCommitSHAs: ReadonlyArray<string>
 

app/src/lib/compare.ts

@@ -65,13 +65,21 @@ export function compareDescending<T>(x: T, y: T): number {
   return 0
 }
 
+/**
+ * Compares the two strings in a case-insensitive manner and returns a value
+ * indicating whether these are equal
+ */
+export function caseInsensitiveEquals(x: string, y: string): boolean {
+  return x.toLowerCase() === y.toLowerCase()
+}
+
 /**
  * Compares the two strings in a case-insensitive manner and returns a value
  * indicating whether one is greater than the other. When the return value is
  * used in a sort operation the comparands will be sorted in ascending order.
  */
 export function caseInsensitiveCompare(x: string, y: string): number {
-  return compare(x.toLowerCase(), y.toLocaleLowerCase())
+  return compare(x.toLowerCase(), y.toLowerCase())
 }
 
 /**
@@ -80,5 +88,5 @@ export function caseInsensitiveCompare(x: string, y: string): number {
  * used in a sort operation the comparands will be sorted in descending order.
  */
 export function caseInsensitiveCompareDescending(x: string, y: string): number {
-  return compareDescending(x.toLowerCase(), y.toLocaleLowerCase())
+  return compareDescending(x.toLowerCase(), y.toLowerCase())
 }

app/src/lib/databases/github-user-database.ts

@@ -30,8 +30,8 @@ export interface IMentionableAssociation {
 }
 
 export class GitHubUserDatabase extends BaseDatabase {
-  public users: Dexie.Table<IGitHubUser, number>
-  public mentionables: Dexie.Table<IMentionableAssociation, number>
+  public users!: Dexie.Table<IGitHubUser, number>
+  public mentionables!: Dexie.Table<IMentionableAssociation, number>
 
   public constructor(name: string, schemaVersion?: number) {
     super(name, schemaVersion)

app/src/lib/databases/issues-database.ts

@@ -10,7 +10,7 @@ export interface IIssue {
 }
 
 export class IssuesDatabase extends BaseDatabase {
-  public issues: Dexie.Table<IIssue, number>
+  public issues!: Dexie.Table<IIssue, number>
 
   public constructor(name: string, schemaVersion?: number) {
     super(name, schemaVersion)

app/src/lib/databases/pull-request-database.ts

@@ -70,8 +70,8 @@ export interface IPullRequestStatus {
 }
 
 export class PullRequestDatabase extends BaseDatabase {
-  public pullRequests: Dexie.Table<IPullRequest, number>
-  public pullRequestStatus: Dexie.Table<IPullRequestStatus, number>
+  public pullRequests!: Dexie.Table<IPullRequest, number>
+  public pullRequestStatus!: Dexie.Table<IPullRequestStatus, number>
 
   public constructor(name: string, schemaVersion?: number) {
     super(name, schemaVersion)

app/src/lib/databases/repositories-database.ts

@@ -30,13 +30,13 @@ export interface IDatabaseRepository {
 /** The repositories database. */
 export class RepositoriesDatabase extends BaseDatabase {
   /** The local repositories table. */
-  public repositories: Dexie.Table<IDatabaseRepository, number>
+  public repositories!: Dexie.Table<IDatabaseRepository, number>
 
   /** The GitHub repositories table. */
-  public gitHubRepositories: Dexie.Table<IDatabaseGitHubRepository, number>
+  public gitHubRepositories!: Dexie.Table<IDatabaseGitHubRepository, number>
 
   /** The GitHub repository owners table. */
-  public owners: Dexie.Table<IDatabaseOwner, number>
+  public owners!: Dexie.Table<IDatabaseOwner, number>
 
   /**
    * Initialize a new repository database.

app/src/lib/diff-parser.ts

@@ -58,7 +58,7 @@ export class DiffParser {
    * The offset into the text property where the current line starts (ie either zero
    * or one character ahead of the last newline character).
    */
-  private ls: number
+  private ls!: number
 
   /**
    * Line end pointer.
@@ -66,12 +66,12 @@ export class DiffParser {
    * The offset into the text property where the current line ends (ie it points to
    * the newline character) or -1 if the line boundary hasn't been determined yet
    */
-  private le: number
+  private le!: number
 
   /**
    * The text buffer containing the raw, unified diff output to be parsed
    */
-  private text: string
+  private text!: string
 
   public constructor() {
     this.reset()

app/src/lib/dispatcher/dispatcher.ts

@@ -487,8 +487,8 @@ export class Dispatcher {
   }
 
   /** Update the repository's issues from GitHub. */
-  public updateIssues(repository: GitHubRepository): Promise<void> {
-    return this.appStore._updateIssues(repository)
+  public refreshIssues(repository: GitHubRepository): Promise<void> {
+    return this.appStore._refreshIssues(repository)
   }
 
   /** End the Welcome flow. */
@@ -806,6 +806,18 @@ export class Dispatcher {
         } catch (e) {
           rejectOAuthRequest(e)
         }
+
+        if (__DARWIN__) {
+          // workaround for user reports that the application doesn't receive focus
+          // after completing the OAuth signin in the browser
+          const window = remote.getCurrentWindow()
+          if (!window.isFocused()) {
+            log.info(
+              `refocusing the main window after the OAuth flow is completed`
+            )
+            window.focus()
+          }
+        }
         break
 
       case 'open-repository-from-url':

app/src/lib/feature-flag.ts

@@ -26,8 +26,8 @@ function enableBetaFeatures(): boolean {
   return enableDevelopmentFeatures() || __RELEASE_CHANNEL__ === 'beta'
 }
 
-/** Should PR integration be enabled? */
-export function enablePRIntegration(): boolean {
+/** Should the new Compare view be enabled? */
+export function enableCompareBranch(): boolean {
   return enableBetaFeatures()
 }
 

app/src/lib/file-system.ts

@@ -76,9 +76,14 @@ export function tailByLine(
   cb: (line: string) => void
 ): Disposable {
   const tailer = new Tailer(path)
-  const disposable = tailer.onDataAvailable(stream => {
+
+  const onErrorDisposable = tailer.onError(error => {
+    log.warn(`Unable to tail path: ${path}`, error)
+  })
+
+  const onDataDisposable = tailer.onDataAvailable(stream => {
     byline(stream).on('data', (buffer: Buffer) => {
-      if (disposable.disposed) {
+      if (onDataDisposable.disposed) {
         return
       }
 
@@ -90,7 +95,8 @@ export function tailByLine(
   tailer.start()
 
   return new Disposable(() => {
-    disposable.dispose()
+    onDataDisposable.dispose()
+    onErrorDisposable.dispose()
     tailer.stop()
   })
 }

app/src/lib/git/core.ts

@@ -245,6 +245,8 @@ function getDescriptionForError(error: DugiteError): string {
       return 'This branch cannot be deleted from the remote repository because it is marked as protected.'
     case DugiteError.ProtectedBranchRequiredStatus:
       return 'The push was rejected by the remote server because a required status check has not been satisfied.'
+    case DugiteError.BranchRenameFailed:
+      return 'The branch could not be renamed.'
     default:
       return assertNever(error, `Unknown error: ${error}`)
   }

app/src/lib/git/diff.ts

@@ -17,6 +17,8 @@ import {
   Image,
   LineEndingsChange,
   parseLineEndingText,
+  ILargeTextDiff,
+  IUnrenderableDiff,
 } from '../../models/diff'
 
 import { spawnAndComplete } from './spawn'
@@ -24,23 +26,23 @@ import { spawnAndComplete } from './spawn'
 import { DiffParser } from '../diff-parser'
 
 /**
- * V8 has a limit on the size of string it can create, and unless we want to
+ * V8 has a limit on the size of string it can create (~256MB), and unless we want to
  * trigger an unhandled exception we need to do the encoding conversion by hand.
  *
  * This is a hard limit on how big a buffer can be and still be converted into
  * a string.
  */
-const MaxDiffBufferSize = 268435441
+const MaxDiffBufferSize = 70e6 // 70MB in decimal
 
 /**
  * Where `MaxDiffBufferSize` is a hard limit, this is a suggested limit. Diffs
  * bigger than this _could_ be displayed but it might cause some slowness.
  */
-const MaxReasonableDiffSize = 3000000
+const MaxReasonableDiffSize = MaxDiffBufferSize / 16 // ~4.375MB in decimal
 
 /**
  * The longest line length we should try to display. If a diff has a line longer
- * than this, we probably shouldn't attempt it.
+ * than this, we probably shouldn't attempt it
  */
 const MaxLineLength = 500000
 
@@ -48,15 +50,15 @@ const MaxLineLength = 500000
  * Utility function to check whether parsing this buffer is going to cause
  * issues at runtime.
  *
- * @param output A buffer of binary text from a spawned process
+ * @param buffer A buffer of binary text from a spawned process
  */
 function isValidBuffer(buffer: Buffer) {
-  return buffer.length < MaxDiffBufferSize
+  return buffer.length <= MaxDiffBufferSize
 }
 
 /** Is the buffer too large for us to reasonably represent? */
 function isBufferTooLarge(buffer: Buffer) {
-  return !isValidBuffer(buffer) || buffer.length >= MaxReasonableDiffSize
+  return buffer.length >= MaxReasonableDiffSize
 }
 
 /** Is the diff too large for us to reasonably represent? */
@@ -75,7 +77,14 @@ function isDiffTooLarge(diff: IRawDiff) {
 /**
  *  Defining the list of known extensions we can render inside the app
  */
-const imageFileExtensions = new Set(['.png', '.jpg', '.jpeg', '.gif', '.ico'])
+const imageFileExtensions = new Set([
+  '.png',
+  '.jpg',
+  '.jpeg',
+  '.gif',
+  '.ico',
+  '.webp',
+])
 
 /**
  * Render the difference between a file in the given commit and its parent
@@ -110,16 +119,8 @@ export async function getCommitDiff(
     repository.path,
     'getCommitDiff'
   )
-  if (isBufferTooLarge(output)) {
-    return { kind: DiffType.TooLarge, length: output.length }
-  }
 
-  const diffText = diffFromRawDiffOutput(output)
-  if (isDiffTooLarge(diffText)) {
-    return { kind: DiffType.TooLarge, length: output.length }
-  }
-
-  return convertDiff(repository, file, diffText, commitish)
+  return buildDiff(output, repository, file, commitish)
 }
 
 /**
@@ -196,20 +197,9 @@ export async function getWorkingDirectoryDiff(
     'getWorkingDirectoryDiff',
     successExitCodes
   )
-  if (isBufferTooLarge(output)) {
-    // we know we can't transform this process output into a diff, so let's
-    // just return a placeholder for now that we can display to the user
-    // to say we're at the limits of the runtime
-    return { kind: DiffType.TooLarge, length: output.length }
-  }
-
-  const diffText = diffFromRawDiffOutput(output)
-  if (isDiffTooLarge(diffText)) {
-    return { kind: DiffType.TooLarge, length: output.length }
-  }
-
   const lineEndingsChange = parseLineEndingsWarning(error)
-  return convertDiff(repository, file, diffText, 'HEAD', lineEndingsChange)
+
+  return buildDiff(output, repository, file, 'HEAD', lineEndingsChange)
 }
 
 async function getImageDiff(
@@ -314,6 +304,9 @@ function getMediaType(extension: string) {
   if (extension === '.ico') {
     return 'image/x-icon'
   }
+  if (extension === '.webp') {
+    return 'image/webp'
+  }
 
   // fallback value as per the spec
   return 'text/plain'
@@ -365,6 +358,37 @@ function diffFromRawDiffOutput(output: Buffer): IRawDiff {
   return parser.parse(pieces[pieces.length - 1])
 }
 
+function buildDiff(
+  buffer: Buffer,
+  repository: Repository,
+  file: FileChange,
+  commitish: string,
+  lineEndingsChange?: LineEndingsChange
+): Promise<IDiff> {
+  if (!isValidBuffer(buffer)) {
+    // the buffer's diff is too large to be renderable in the UI
+    return Promise.resolve<IUnrenderableDiff>({ kind: DiffType.Unrenderable })
+  }
+
+  const diff = diffFromRawDiffOutput(buffer)
+
+  if (isBufferTooLarge(buffer) || isDiffTooLarge(diff)) {
+    // we don't want to render by default
+    // but we keep it as an option by
+    // passing in text and hunks
+    const largeTextDiff: ILargeTextDiff = {
+      kind: DiffType.LargeText,
+      text: diff.contents,
+      hunks: diff.hunks,
+      lineEndingsChange,
+    }
+
+    return Promise.resolve(largeTextDiff)
+  }
+
+  return convertDiff(repository, file, diff, commitish, lineEndingsChange)
+}
+
 /**
  * Retrieve the binary contents of a blob from the object database
  *
@@ -381,11 +405,7 @@ export async function getBlobImage(
 ): Promise<Image> {
   const extension = Path.extname(path)
   const contents = await getBlobContents(repository, commitish, path)
-  const diff: Image = {
-    contents: contents.toString('base64'),
-    mediaType: getMediaType(extension),
-  }
-  return diff
+  return new Image(contents.toString('base64'), getMediaType(extension))
 }
 /**
  * Retrieve the binary contents of a blob from the working directory
@@ -403,9 +423,8 @@ export async function getWorkingDirectoryImage(
   const contents = await fileSystem.readFile(
     Path.join(repository.path, file.path)
   )
-  const diff: Image = {
-    contents: contents.toString('base64'),
-    mediaType: getMediaType(Path.extname(file.path)),
-  }
-  return diff
+  return new Image(
+    contents.toString('base64'),
+    getMediaType(Path.extname(file.path))
+  )
 }

app/src/lib/git/for-each-ref.ts

@@ -3,11 +3,14 @@ import { Repository } from '../../models/repository'
 import { Commit } from '../../models/commit'
 import { Branch, BranchType } from '../../models/branch'
 import { CommitIdentity } from '../../models/commit-identity'
+import { ForkedRemotePrefix } from '../../models/remote'
 import {
   getTrailerSeparatorCharacters,
   parseRawUnfoldedTrailers,
 } from './interpret-trailers'
 
+const ForksReferencesPrefix = `refs/remotes/${ForkedRemotePrefix}`
+
 /** Get all the branches. */
 export async function getBranches(
   repository: Repository,
@@ -102,6 +105,14 @@ export async function getBranches(
       continue
     }
 
+    if (ref.startsWith(ForksReferencesPrefix)) {
+      // hide refs from our known remotes as these are considered plumbing
+      // and can add noise to everywhere in the user interface where we
+      // display branches as forks will likely contain duplicates of the same
+      // ref names
+      continue
+    }
+
     branches.push(
       new Branch(name, upstream.length > 0 ? upstream : null, tip, type)
     )

app/src/lib/git/interpret-trailers.ts

@@ -12,6 +12,14 @@ export interface ITrailer {
   readonly value: string
 }
 
+/**
+ * Gets a value indicating whether the trailer token is
+ * Co-Authored-By. Does not validate the token value.
+ */
+export function isCoAuthoredByTrailer(trailer: ITrailer) {
+  return trailer.token.toLowerCase() === 'co-authored-by'
+}
+
 /**
  * Parse a string containing only unfolded trailers produced by
  * git-interpret-trailers --only-input --only-trailers --unfold or

app/src/lib/git/remote.ts

@@ -1,6 +1,7 @@
 import { git } from './core'
 import { Repository } from '../../models/repository'
 import { IRemote } from '../../models/remote'
+import { findDefaultRemote } from '../stores/helpers/find-default-remote'
 
 /** Get the remote names. */
 export async function getRemotes(
@@ -21,18 +22,7 @@ export async function getRemotes(
 export async function getDefaultRemote(
   repository: Repository
 ): Promise<IRemote | null> {
-  const remotes = await getRemotes(repository)
-  if (remotes.length === 0) {
-    return null
-  }
-
-  const remote = remotes.find(x => x.name === 'origin')
-
-  if (remote) {
-    return remote
-  }
-
-  return remotes[0]
+  return findDefaultRemote(await getRemotes(repository))
 }
 
 /** Add a new remote with the given URL. */
@@ -40,8 +30,10 @@ export async function addRemote(
   repository: Repository,
   name: string,
   url: string
-): Promise<void> {
+): Promise<IRemote> {
   await git(['remote', 'add', name, url], repository.path, 'addRemote')
+
+  return { url, name }
 }
 
 /** Removes an existing remote, or silently errors if it doesn't exist */

app/src/lib/git/submodule.ts

@@ -1,10 +1,22 @@
 import { git } from './core'
 import { Repository } from '../../models/repository'
 import { SubmoduleEntry } from '../../models/submodule'
+import { pathExists } from '../file-system'
+import * as Path from 'path'
 
 export async function listSubmodules(
   repository: Repository
 ): Promise<ReadonlyArray<SubmoduleEntry>> {
+  const [submodulesFile, submodulesDir] = await Promise.all([
+    pathExists(Path.join(repository.path, '.gitmodules')),
+    pathExists(Path.join(repository.path, '.git', 'modules')),
+  ])
+
+  if (!submodulesFile && !submodulesDir) {
+    log.info('No submodules found. Skipping "git submodule status"')
+    return []
+  }
+
   // We don't recurse when listing submodules here because we don't have a good
   // story about managing these currently. So for now we're only listing
   // changes to the top-level submodules to be consistent with `git status`

app/src/lib/is-git-on-path.ts

@@ -1,4 +1,5 @@
 import { spawn } from 'child_process'
+import * as Path from 'path'
 
 export function isGitOnPath(): Promise<boolean> {
   // Modern versions of macOS ship with a Git shim that guides you through
@@ -11,12 +12,20 @@ export function isGitOnPath(): Promise<boolean> {
 
   // adapted from http://stackoverflow.com/a/34953561/1363815
   return new Promise<boolean>((resolve, reject) => {
-    const process = spawn('where', ['git'])
-
     if (__WIN32__) {
+      const windowsRoot = process.env.SystemRoot || 'C:\\Windows'
+      const wherePath = Path.join(windowsRoot, 'System32', 'where.exe')
+
+      const cp = spawn(wherePath, ['git'])
+
+      cp.on('error', error => {
+        log.warn('Unable to spawn where.exe', error)
+        resolve(false)
+      })
+
       // `where` will return 0 when the executable
       // is found under PATH, or 1 if it cannot be found
-      process.on('close', function(code) {
+      cp.on('close', function(code) {
         resolve(code === 0)
       })
       return

app/src/lib/menu-item.ts

@@ -0,0 +1,21 @@
+export interface IMenuItem {
+  /** The user-facing label. */
+  readonly label?: string
+
+  /** The action to invoke when the user selects the item. */
+  readonly action?: () => void
+
+  /** The type of item. */
+  readonly type?: 'separator'
+
+  /** Is the menu item enabled? Defaults to true. */
+  readonly enabled?: boolean
+
+  /**
+   * The predefined behavior of the menu item.
+   *
+   * When specified the click property will be ignored.
+   * See https://electronjs.org/docs/api/menu-item#roles
+   */
+  readonly role?: string
+}

app/src/lib/repository-matching.ts

@@ -4,8 +4,11 @@ import * as Path from 'path'
 import { CloningRepository } from '../models/cloning-repository'
 import { Repository } from '../models/repository'
 import { Account } from '../models/account'
+import { IRemote } from '../models/remote'
 import { getHTMLURL } from './api'
 import { parseRemote } from './remote-parsing'
+import { caseInsensitiveEquals } from './compare'
+import { GitHubRepository } from '../models/github-repository'
 
 export interface IMatchedGitHubRepository {
   /**
@@ -92,3 +95,56 @@ export function matchExistingRepository(
     }) || null
   )
 }
+
+/**
+ * Check whether or not a GitHub repository matches a given remote.
+ *
+ * @param gitHubRepository the repository containing information from the GitHub API
+ * @param remote the remote details found in the Git repository
+ */
+export function repositoryMatchesRemote(
+  gitHubRepository: GitHubRepository,
+  remote: IRemote
+): boolean {
+  return (
+    urlMatchesRemote(gitHubRepository.htmlURL, remote) ||
+    urlMatchesRemote(gitHubRepository.cloneURL, remote)
+  )
+}
+
+/**
+ * Check whether or not a GitHub repository URL matches a given remote, by
+ * parsing and comparing the structure of the each URL.
+ *
+ * @param url a URL associated with the GitHub repository
+ * @param remote the remote details found in the Git repository
+ */
+export function urlMatchesRemote(url: string | null, remote: IRemote): boolean {
+  if (url == null) {
+    return false
+  }
+
+  const cloneUrl = parseRemote(url)
+  const remoteUrl = parseRemote(remote.url)
+
+  if (remoteUrl == null || cloneUrl == null) {
+    return false
+  }
+
+  if (!caseInsensitiveEquals(remoteUrl.hostname, cloneUrl.hostname)) {
+    return false
+  }
+
+  if (remoteUrl.owner == null || cloneUrl.owner == null) {
+    return false
+  }
+
+  if (remoteUrl.name == null || cloneUrl.name == null) {
+    return false
+  }
+
+  return (
+    caseInsensitiveEquals(remoteUrl.owner, cloneUrl.owner) &&
+    caseInsensitiveEquals(remoteUrl.name, cloneUrl.name)
+  )
+}

app/src/lib/shells/win32.ts

@@ -1,7 +1,9 @@
 import { spawn, ChildProcess } from 'child_process'
 import * as Path from 'path'
-import { assertNever } from '../fatal-error'
 import { enumerateValues, HKEY, RegistryValueType } from 'registry-js'
+
+import { pathExists } from '../file-system'
+import { assertNever } from '../fatal-error'
 import { IFoundShell } from './found-shell'
 
 export enum Shell {
@@ -43,75 +45,127 @@ export async function getAvailableShells(): Promise<
     },
   ]
 
+  const powerShellPath = await findPowerShell()
+  if (powerShellPath != null) {
+    shells.push({
+      shell: Shell.PowerShell,
+      path: powerShellPath,
+    })
+  }
+
+  const hyperPath = await findHyper()
+  if (hyperPath != null) {
+    shells.push({
+      shell: Shell.Hyper,
+      path: hyperPath,
+    })
+  }
+
+  const gitBashPath = await findGitBash()
+  if (gitBashPath != null) {
+    shells.push({
+      shell: Shell.GitBash,
+      path: gitBashPath,
+    })
+  }
+
+  return shells
+}
+
+async function findPowerShell(): Promise<string | null> {
   const powerShell = enumerateValues(
     HKEY.HKEY_LOCAL_MACHINE,
     'Software\\Microsoft\\Windows\\CurrentVersion\\App Paths\\PowerShell.exe'
   )
-  if (powerShell.length > 0) {
-    const first = powerShell[0]
 
-    // NOTE:
-    // on Windows 7 these are both REG_SZ, which technically isn't supposed
-    // to contain unexpanded references to environment variables. But given
-    // it's also %SystemRoot% and we do the expanding here I think this is
-    // a fine workaround to do to support the maximum number of setups.
+  if (powerShell.length === 0) {
+    return null
+  }
 
-    if (
-      first.type === RegistryValueType.REG_EXPAND_SZ ||
-      first.type === RegistryValueType.REG_SZ
-    ) {
-      const path = first.data.replace(
-        /^%SystemRoot%/i,
-        process.env.SystemRoot || 'C:\\Windows'
+  const first = powerShell[0]
+
+  // NOTE:
+  // on Windows 7 these are both REG_SZ, which technically isn't supposed
+  // to contain unexpanded references to environment variables. But given
+  // it's also %SystemRoot% and we do the expanding here I think this is
+  // a fine workaround to do to support the maximum number of setups.
+
+  if (
+    first.type === RegistryValueType.REG_EXPAND_SZ ||
+    first.type === RegistryValueType.REG_SZ
+  ) {
+    const path = first.data.replace(
+      /^%SystemRoot%/i,
+      process.env.SystemRoot || 'C:\\Windows'
+    )
+
+    if (await pathExists(path)) {
+      return path
+    } else {
+      log.debug(
+        `[PowerShell] registry entry found but does not exist at '${path}'`
       )
-      shells.push({
-        shell: Shell.PowerShell,
-        path,
-      })
     }
   }
 
+  return null
+}
+
+async function findHyper(): Promise<string | null> {
   const hyper = enumerateValues(
     HKEY.HKEY_CURRENT_USER,
     'Software\\Classes\\Directory\\Background\\shell\\Hyper\\command'
   )
-  if (hyper.length > 0) {
-    const first = hyper[0]
-    if (first.type === RegistryValueType.REG_SZ) {
-      // Registry key is structured as "{installationPath}\app-x.x.x\Hyper.exe" "%V"
 
-      // This regex is designed to get the path to the version-specific Hyper.
-      // commandPieces = ['"{installationPath}\app-x.x.x\Hyper.exe"', '"', '{installationPath}\app-x.x.x\Hyper.exe', ...]
-      const commandPieces = first.data.match(/(["'])(.*?)\1/)
-      const path = commandPieces
-        ? commandPieces[2]
-        : process.env.LocalAppData.concat('\\hyper\\Hyper.exe') // fall back to the launcher in install root
-      shells.push({
-        shell: Shell.Hyper,
-        path: path,
-      })
+  if (hyper.length === 0) {
+    return null
+  }
+
+  const first = hyper[0]
+  if (first.type === RegistryValueType.REG_SZ) {
+    // Registry key is structured as "{installationPath}\app-x.x.x\Hyper.exe" "%V"
+
+    // This regex is designed to get the path to the version-specific Hyper.
+    // commandPieces = ['"{installationPath}\app-x.x.x\Hyper.exe"', '"', '{installationPath}\app-x.x.x\Hyper.exe', ...]
+    const commandPieces = first.data.match(/(["'])(.*?)\1/)
+    const path = commandPieces
+      ? commandPieces[2]
+      : process.env.LocalAppData.concat('\\hyper\\Hyper.exe') // fall back to the launcher in install root
+
+    if (await pathExists(path)) {
+      return path
+    } else {
+      log.debug(`[Hyper] registry entry found but does not exist at '${path}'`)
     }
   }
 
-  const gitBash = enumerateValues(
+  return null
+}
+
+async function findGitBash(): Promise<string | null> {
+  const registryPath = enumerateValues(
     HKEY.HKEY_LOCAL_MACHINE,
     'SOFTWARE\\GitForWindows'
   )
 
-  if (gitBash.length > 0) {
-    const installPathEntry = gitBash.find(e => e.name === 'InstallPath')
-    if (
-      installPathEntry &&
-      installPathEntry.type === RegistryValueType.REG_SZ
-    ) {
-      shells.push({
-        shell: Shell.GitBash,
-        path: Path.join(installPathEntry.data, 'git-bash.exe'),
-      })
+  if (registryPath.length === 0) {
+    return null
+  }
+
+  const installPathEntry = registryPath.find(e => e.name === 'InstallPath')
+  if (installPathEntry && installPathEntry.type === RegistryValueType.REG_SZ) {
+    const path = Path.join(installPathEntry.data, 'git-bash.exe')
+
+    if (await pathExists(path)) {
+      return path
+    } else {
+      log.debug(
+        `[Git Bash] registry entry found but does not exist at '${path}'`
+      )
     }
   }
 
-  return shells
+  return null
 }
 
 export function launch(

app/src/lib/stats/stats-database.ts

@@ -37,11 +37,14 @@ export interface IDailyMeasures {
 
   /** The number of partial commits. */
   readonly partialCommits: number
+
+  /** The number of commits created with one or more co-authors. */
+  readonly coAuthoredCommits: number
 }
 
 export class StatsDatabase extends Dexie {
-  public launches: Dexie.Table<ILaunchStats, number>
-  public dailyMeasures: Dexie.Table<IDailyMeasures, number>
+  public launches!: Dexie.Table<ILaunchStats, number>
+  public dailyMeasures!: Dexie.Table<IDailyMeasures, number>
 
   public constructor(name: string) {
     super(name)

app/src/lib/stats/stats-store.ts

@@ -28,6 +28,7 @@ const DefaultDailyMeasures: IDailyMeasures = {
   commits: 0,
   partialCommits: 0,
   openShellCount: 0,
+  coAuthoredCommits: 0,
 }
 
 interface ICalculatedStats {
@@ -279,6 +280,13 @@ export class StatsStore {
     }))
   }
 
+  /** Record that a commit was created with one or more co-authors. */
+  public recordCoAuthoredCommit(): Promise<void> {
+    return this.updateDailyMeasures(m => ({
+      coAuthoredCommits: m.coAuthoredCommits + 1,
+    }))
+  }
+
   /** Record that the user opened a shell. */
   public recordOpenShell(): Promise<void> {
     return this.updateDailyMeasures(m => ({

app/src/lib/stores/accounts-store.ts

@@ -24,6 +24,16 @@ interface IEmail {
   readonly visibility: EmailVisibility
 }
 
+function isKeyChainError(e: any) {
+  const error = e as Error
+  return (
+    error.message &&
+    error.message.startsWith(
+      'The user name or passphrase you entered is not correct'
+    )
+  )
+}
+
 /** The data-only interface for storage. */
 interface IAccount {
   readonly token: string
@@ -83,7 +93,16 @@ export class AccountsStore extends BaseStore {
       )
     } catch (e) {
       log.error(`Error adding account '${account.login}'`, e)
-      this.emitError(e)
+
+      if (__DARWIN__ && isKeyChainError(e)) {
+        this.emitError(
+          new Error(
+            `GitHub Desktop was unable to store the account token in the keychain. Please check you have unlocked access to the 'login' keychain.`
+          )
+        )
+      } else {
+        this.emitError(e)
+      }
       return
     }
 

app/src/lib/stores/app-store.ts

@@ -16,6 +16,7 @@ import {
   Progress,
   ImageDiffType,
   IRevertProgress,
+  IFetchProgress,
 } from '../app-state'
 import { Account } from '../../models/account'
 import { Repository } from '../../models/repository'
@@ -29,6 +30,7 @@ import { DiffSelection, DiffSelectionType, DiffType } from '../../models/diff'
 import {
   matchGitHubRepository,
   IMatchedGitHubRepository,
+  repositoryMatchesRemote,
 } from '../../lib/repository-matching'
 import { API, getAccountForEndpoint, IAPIUser } from '../../lib/api'
 import { caseInsensitiveCompare } from '../compare'
@@ -75,6 +77,7 @@ import {
   getMergeBase,
   getRemotes,
   ITrailer,
+  isCoAuthoredByTrailer,
 } from '../git'
 
 import { launchExternalEditor } from '../editors'
@@ -91,7 +94,6 @@ import {
   EmojiStore,
   GitHubUserStore,
   CloningRepositoriesStore,
-  ForkedRemotePrefix,
 } from '../stores'
 import { validatedRepositoryPath } from './helpers/validated-repository-path'
 import { IGitAccount } from '../git/authentication'
@@ -117,7 +119,7 @@ import { Owner } from '../../models/owner'
 import { PullRequest } from '../../models/pull-request'
 import { PullRequestUpdater } from './helpers/pull-request-updater'
 import * as QueryString from 'querystring'
-import { IRemote } from '../../models/remote'
+import { IRemote, ForkedRemotePrefix } from '../../models/remote'
 import { IAuthor } from '../../models/author'
 
 /**
@@ -412,7 +414,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
       },
       commitAuthor: null,
       gitHubUsers: new Map<string, IGitHubUser>(),
-      commits: new Map<string, Commit>(),
+      commitLookup: new Map<string, Commit>(),
       localCommitSHAs: [],
       aheadBehind: null,
       remote: null,
@@ -571,7 +573,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
     }))
 
     this.updateRepositoryState(repository, state => ({
-      commits: gitStore.commits,
+      commitLookup: gitStore.commitLookup,
       localCommitSHAs: gitStore.localCommitSHAs,
       aheadBehind: gitStore.aheadBehind,
       remote: gitStore.remote,
@@ -821,7 +823,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
     const gitHubRepository = repository.gitHubRepository
 
     if (gitHubRepository != null) {
-      this._updateIssues(gitHubRepository)
+      this._refreshIssues(gitHubRepository)
       this.loadPullRequests(repository, async () => {
         const promiseForPRs = this.pullRequestStore.fetchPullRequestsFromCache(
           gitHubRepository
@@ -869,14 +871,14 @@ export class AppStore extends TypedBaseStore<IAppState> {
     return this._repositoryWithRefreshedGitHubRepository(repository)
   }
 
-  public async _updateIssues(repository: GitHubRepository) {
+  public async _refreshIssues(repository: GitHubRepository) {
     const user = getAccountForEndpoint(this.accounts, repository.endpoint)
     if (!user) {
       return
     }
 
     try {
-      await this._issuesStore.fetchIssues(repository, user)
+      await this._issuesStore.refreshIssues(repository, user)
     } catch (e) {
       log.warn(`Unable to fetch issues for ${repository.fullName}`, e)
     }
@@ -1399,6 +1401,10 @@ export class AppStore extends TypedBaseStore<IAppState> {
         this.statsStore.recordPartialCommit()
       }
 
+      if (trailers != null && trailers.some(isCoAuthoredByTrailer)) {
+        this.statsStore.recordCoAuthoredCommit()
+      }
+
       await this._refreshRepository(repository)
       await this.refreshChangesSection(repository, {
         includingStatus: true,
@@ -1500,12 +1506,11 @@ export class AppStore extends TypedBaseStore<IAppState> {
     }
 
     await Promise.all([
-      gitStore.loadCurrentRemote(),
+      gitStore.loadRemotes(),
       gitStore.updateLastFetched(),
       this.refreshAuthor(repository),
       gitStore.loadContextualCommitMessage(),
       refreshSectionPromise,
-      gitStore.loadUpstreamRemote(),
     ])
 
     this._updateCurrentPullRequest(repository)
@@ -2216,7 +2221,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
     await gitStore.performFailableOperation(() =>
       addRemote(repository, 'origin', apiRepository.clone_url)
     )
-    await gitStore.loadCurrentRemote()
+    await gitStore.loadRemotes()
 
     // skip pushing if the current branch is a detached HEAD or the repository
     // is unborn
@@ -2340,17 +2345,48 @@ export class AppStore extends TypedBaseStore<IAppState> {
     )
   }
 
-  /** Fetch the repository. */
+  /**
+   * Fetch all relevant remotes in the the repository.
+   *
+   * See gitStore.fetch for more details.
+   *
+   * Note that this method will not perform the fetch of the specified remote
+   * if _any_ fetches or pulls are currently in-progress.
+   */
   public _fetch(repository: Repository, fetchType: FetchType): Promise<void> {
     return this.withAuthenticatingUser(repository, (repository, account) => {
       return this.performFetch(repository, account, fetchType)
     })
   }
 
+  /**
+   * Fetch a particular remote in a repository.
+   *
+   * Note that this method will not perform the fetch of the specified remote
+   * if _any_ fetches or pulls are currently in-progress.
+   */
+  private _fetchRemote(
+    repository: Repository,
+    remote: IRemote,
+    fetchType: FetchType
+  ): Promise<void> {
+    return this.withAuthenticatingUser(repository, (repository, account) => {
+      return this.performFetch(repository, account, fetchType, [remote])
+    })
+  }
+
+  /**
+   * Fetch all relevant remotes or one or more given remotes in the repository.
+   *
+   * @param remotes Optional, one or more remotes to fetch if undefined all
+   *                relevant remotes will be fetched. See gitStore.fetch for
+   *                more detail on what constitutes a relevant remote.
+   */
   private async performFetch(
     repository: Repository,
     account: IGitAccount | null,
-    fetchType: FetchType
+    fetchType: FetchType,
+    remotes?: IRemote[]
   ): Promise<void> {
     await this.withPushPull(repository, async () => {
       const gitStore = this.getGitStore(repository)
@@ -2360,12 +2396,23 @@ export class AppStore extends TypedBaseStore<IAppState> {
         const refreshWeight = 0.1
         const isBackgroundTask = fetchType === FetchType.BackgroundTask
 
-        await gitStore.fetch(account, isBackgroundTask, progress => {
+        const progressCallback = (progress: IFetchProgress) => {
           this.updatePushPullFetchProgress(repository, {
             ...progress,
             value: progress.value * fetchWeight,
           })
-        })
+        }
+
+        if (remotes === undefined) {
+          await gitStore.fetch(account, isBackgroundTask, progressCallback)
+        } else {
+          await gitStore.fetchRemotes(
+            account,
+            remotes,
+            isBackgroundTask,
+            progressCallback
+          )
+        }
 
         const refreshTitle = __DARWIN__
           ? 'Refreshing Repository'
@@ -2392,6 +2439,9 @@ export class AppStore extends TypedBaseStore<IAppState> {
 
         if (fetchType === FetchType.UserInitiatedTask) {
           this._refreshPullRequests(repository)
+          if (repository.gitHubRepository != null) {
+            this._refreshIssues(repository.gitHubRepository)
+          }
         }
       }
     })
@@ -2668,15 +2718,11 @@ export class AppStore extends TypedBaseStore<IAppState> {
     return this.signInStore.setTwoFactorOTP(otp)
   }
 
-  public _setAppFocusState(isFocused: boolean): Promise<void> {
-    const changed = this.appIsFocused !== isFocused
-    this.appIsFocused = isFocused
-
-    if (changed) {
+  public async _setAppFocusState(isFocused: boolean): Promise<void> {
+    if (this.appIsFocused !== isFocused) {
+      this.appIsFocused = isFocused
       this.emitUpdate()
     }
-
-    return Promise.resolve()
   }
 
   /**
@@ -2739,7 +2785,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
       // the accounts field
       const accounts = await this.accountsStore.getAll()
       const repoState = selectedState.state
-      const commits = repoState.commits.values()
+      const commits = repoState.commitLookup.values()
       this.loadAndCacheUsers(selectedState.repository, accounts, commits)
     }
   }
@@ -2822,7 +2868,12 @@ export class AppStore extends TypedBaseStore<IAppState> {
       await this.repositoriesStore.removeRepository(id)
     }
 
-    this._showFoldout({ type: FoldoutType.Repository })
+    const allRepositories = await this.repositoriesStore.getAll()
+    if (allRepositories.length === 0) {
+      this._closeFoldout(FoldoutType.Repository)
+    } else {
+      this._showFoldout({ type: FoldoutType.Repository })
+    }
   }
 
   public async _cloneAgain(url: string, path: string): Promise<void> {
@@ -3128,7 +3179,7 @@ export class AppStore extends TypedBaseStore<IAppState> {
         pr =>
           pr.head.ref === upstream &&
           pr.head.gitHubRepository != null &&
-          pr.head.gitHubRepository.cloneURL === remote.url
+          repositoryMatchesRemote(pr.head.gitHubRepository, remote)
       ) || null
 
     return pr
@@ -3233,7 +3284,16 @@ export class AppStore extends TypedBaseStore<IAppState> {
 
     if (isRefInThisRepo) {
       // We need to fetch FIRST because someone may have created a PR since the last fetch
-      await this._fetch(repository, FetchType.UserInitiatedTask)
+      const defaultRemote = await getDefaultRemote(repository)
+      // TODO: I think we could skip this fetch if we know that we have the branch locally
+      // already. That way we'd match the behavior of checking out a branch.
+      if (defaultRemote) {
+        await this._fetchRemote(
+          repository,
+          defaultRemote,
+          FetchType.UserInitiatedTask
+        )
+      }
       await this._checkoutBranch(repository, head.ref)
     } else if (head.gitHubRepository != null) {
       const cloneURL = forceUnwrap(
@@ -3244,11 +3304,11 @@ export class AppStore extends TypedBaseStore<IAppState> {
         head.gitHubRepository.owner.login
       )
       const remotes = await getRemotes(repository)
-      const remote = remotes.find(r => r.name === remoteName)
+      const remote =
+        remotes.find(r => r.name === remoteName) ||
+        (await addRemote(repository, remoteName, cloneURL))
 
-      if (remote == null) {
-        await addRemote(repository, remoteName, cloneURL)
-      } else if (remote.url !== cloneURL) {
+      if (remote.url !== cloneURL) {
         const error = new Error(
           `Expected PR remote ${remoteName} url to be ${cloneURL} got ${
             remote.url
@@ -3259,19 +3319,10 @@ export class AppStore extends TypedBaseStore<IAppState> {
         this.emitError(error)
       }
 
+      await this._fetchRemote(repository, remote, FetchType.UserInitiatedTask)
+
       const gitStore = this.getGitStore(repository)
 
-      await this.withAuthenticatingUser(repository, async (repo, account) => {
-        await gitStore.fetchRemote(account, remoteName, false, progress => {
-          this.updatePushPullFetchProgress(repository, {
-            ...progress,
-            value: progress.value,
-          })
-        })
-      })
-
-      this.updatePushPullFetchProgress(repository, null)
-
       const localBranchName = `pr/${pullRequest.number}`
       const doesBranchExist =
         gitStore.allBranches.find(branch => branch.name === localBranchName) !=

app/src/lib/stores/git-store.ts

@@ -18,7 +18,6 @@ import { queueWorkHigh } from '../../lib/queue-work'
 import {
   reset,
   GitResetMode,
-  getDefaultRemote,
   getRemotes,
   fetch as fetchRepo,
   fetchRefspec,
@@ -26,7 +25,6 @@ import {
   getBranches,
   deleteRef,
   IAheadBehind,
-  getBranchAheadBehind,
   getCommits,
   merge,
   setRemoteURL,
@@ -48,6 +46,7 @@ import {
   mergeTrailers,
   getTrailerSeparatorCharacters,
   parseSingleUnfoldedTrailer,
+  isCoAuthoredByTrailer,
 } from '../git'
 import { IGitAccount } from '../git/authentication'
 import { RetryAction, RetryActionType } from '../retry-actions'
@@ -57,6 +56,7 @@ import {
   findUpstreamRemote,
   UpstreamRemoteName,
 } from './helpers/find-upstream-remote'
+import { findDefaultRemote } from './helpers/find-default-remote'
 import { IAuthor } from '../../models/author'
 import { formatCommitMessage } from '../format-commit-message'
 import { GitAuthor } from '../../models/git-author'
@@ -81,7 +81,7 @@ export class GitStore extends BaseStore {
   private readonly shell: IAppShell
 
   /** The commits keyed by their SHA. */
-  public readonly commits = new Map<string, Commit>()
+  public readonly commitLookup = new Map<string, Commit>()
 
   private _history: ReadonlyArray<string> = new Array()
 
@@ -109,6 +109,8 @@ export class GitStore extends BaseStore {
 
   private _aheadBehind: IAheadBehind | null = null
 
+  private _defaultRemote: IRemote | null = null
+
   private _remote: IRemote | null = null
 
   private _upstream: IRemote | null = null
@@ -280,7 +282,7 @@ export class GitStore extends BaseStore {
     const commits = this._allBranches.map(b => b.tip)
 
     for (const commit of commits) {
-      this.commits.set(commit.sha, commit)
+      this.commitLookup.set(commit.sha, commit)
     }
 
     this.emitNewCommitsLoaded(commits)
@@ -447,7 +449,7 @@ export class GitStore extends BaseStore {
   /** Store the given commits. */
   private storeCommits(commits: ReadonlyArray<Commit>) {
     for (const commit of commits) {
-      this.commits.set(commit.sha, commit)
+      this.commitLookup.set(commit.sha, commit)
     }
   }
 
@@ -543,9 +545,7 @@ export class GitStore extends BaseStore {
     // Next we extract any co-authored-by trailers we
     // can find. We use interpret-trailers for this
     const foundTrailers = await parseTrailers(repository, message)
-    const coAuthorTrailers = foundTrailers.filter(
-      t => t.token.toLowerCase() === 'co-authored-by'
-    )
+    const coAuthorTrailers = foundTrailers.filter(isCoAuthoredByTrailer)
 
     // This is the happy path, nothing more for us to do
     if (coAuthorTrailers.length === 0) {
@@ -714,7 +714,7 @@ export class GitStore extends BaseStore {
   }
 
   /**
-   * Fetch the default and upstream remote, using the given account for
+   * Fetch the default, current, and upstream remotes, using the given account for
    * authentication.
    *
    * @param account          - The account to use for authentication if needed.
@@ -727,22 +727,34 @@ export class GitStore extends BaseStore {
     backgroundTask: boolean,
     progressCallback?: (fetchProgress: IFetchProgress) => void
   ): Promise<void> {
-    const remotes = []
-    const remote = this.remote
-    if (remote) {
-      remotes.push(remote)
+    // Use a map as a simple way of getting a unique set of remotes.
+    // Note that maps iterate in insertion order so the order in which
+    // we insert these will affect the order in which we fetch them
+    const remotes = new Map<string, IRemote>()
+
+    // We want to fetch the current remote first
+    if (this.remote) {
+      remotes.set(this.remote.name, this.remote)
     }
 
-    const upstream = this.upstream
-    if (upstream) {
-      remotes.push(upstream)
+    // And then the default remote if it differs from the current
+    if (this.defaultRemote) {
+      remotes.set(this.defaultRemote.name, this.defaultRemote)
     }
 
-    if (!remotes.length) {
-      return Promise.resolve()
+    // And finally the upstream if we're a fork
+    if (this.upstream) {
+      remotes.set(this.upstream.name, this.upstream)
     }
 
-    return this.fetchRemotes(account, remotes, backgroundTask, progressCallback)
+    if (remotes.size > 0) {
+      await this.fetchRemotes(
+        account,
+        [...remotes.values()],
+        backgroundTask,
+        progressCallback
+      )
+    }
   }
 
   /**
@@ -831,16 +843,6 @@ export class GitStore extends BaseStore {
     }
   }
 
-  /** Calculate the ahead/behind for the current branch. */
-  public async calculateAheadBehindForCurrentBranch(): Promise<void> {
-    if (this.tip.kind === TipState.Valid) {
-      const branch = this.tip.branch
-      this._aheadBehind = await getBranchAheadBehind(this.repository, branch)
-    }
-
-    this.emitUpdate()
-  }
-
   public async loadStatus(): Promise<IStatusResult | null> {
     const status = await this.performFailableOperation(() =>
       getStatus(this.repository)
@@ -856,7 +858,7 @@ export class GitStore extends BaseStore {
 
     if (currentBranch || currentTip) {
       if (currentTip && currentBranch) {
-        const cachedCommit = this.commits.get(currentTip)
+        const cachedCommit = this.commitLookup.get(currentTip)
         const branchTipCommit =
           cachedCommit ||
           (await this.performFailableOperation(() =>
@@ -888,45 +890,29 @@ export class GitStore extends BaseStore {
     return status
   }
 
-  /**
-   * Load the remote for the current branch, or the default remote if no
-   * tracking information found.
-   */
-  public async loadCurrentRemote(): Promise<void> {
-    const tip = this.tip
+  public async loadRemotes(): Promise<void> {
+    const remotes = await getRemotes(this.repository)
+    this._defaultRemote = findDefaultRemote(remotes)
 
-    if (tip.kind === TipState.Valid) {
-      const branch = tip.branch
+    const currentRemoteName =
+      this.tip.kind === TipState.Valid && this.tip.branch.remote !== null
+        ? this.tip.branch.remote
+        : null
 
-      if (branch.remote != null) {
-        const allRemotes = await getRemotes(this.repository)
-        const foundRemote = allRemotes.find(r => r.name === branch.remote)
+    // Load the remote that the current branch is tracking. If the branch
+    // is not tracking any remote or the remote which it's tracking has
+    // been removed we'll default to the default branch.
+    this._remote =
+      currentRemoteName !== null
+        ? remotes.find(r => r.name === currentRemoteName) || this._defaultRemote
+        : this._defaultRemote
 
-        if (foundRemote) {
-          this._remote = foundRemote
-        }
-      }
-    }
-
-    if (this._remote == null) {
-      this._remote = await getDefaultRemote(this.repository)
-    }
-
-    this.emitUpdate()
-  }
-
-  /** Load the upstream remote if it exists. */
-  public async loadUpstreamRemote(): Promise<void> {
     const parent =
       this.repository.gitHubRepository &&
       this.repository.gitHubRepository.parent
-    if (!parent) {
-      return
-    }
 
-    const remotes = await getRemotes(this.repository)
-    const upstream = findUpstreamRemote(parent, remotes)
-    this._upstream = upstream
+    this._upstream = parent ? findUpstreamRemote(parent, remotes) : null
+
     this.emitUpdate()
   }
 
@@ -982,6 +968,11 @@ export class GitStore extends BaseStore {
     return this._aheadBehind
   }
 
+  /** Get the remote we're working with. */
+  public get defaultRemote(): IRemote | null {
+    return this._defaultRemote
+  }
+
   /** Get the remote we're working with. */
   public get remote(): IRemote | null {
     return this._remote
@@ -1060,7 +1051,7 @@ export class GitStore extends BaseStore {
     await this.performFailableOperation(() =>
       setRemoteURL(this.repository, name, url)
     )
-    await this.loadCurrentRemote()
+    await this.loadRemotes()
 
     this.emitUpdate()
   }

app/src/lib/stores/helpers/find-default-remote.ts

@@ -0,0 +1,14 @@
+import { IRemote } from '../../../models/remote'
+
+/**
+ * Attempt to find the remote which we consider to be the "default"
+ * remote, i.e. in most cases the 'origin' remote.
+ *
+ * If no remotes are given this method will return null, if no "default"
+ * branch could be found the first remote is considered the default.
+ *
+ * @param remotes A list of remotes for a given repository
+ */
+export function findDefaultRemote(remotes: ReadonlyArray<IRemote>) {
+  return remotes.find(x => x.name === 'origin') || remotes[0] || null
+}

app/src/lib/stores/issues-store.ts

@@ -48,10 +48,10 @@ export class IssuesStore {
   }
 
   /**
-   * Fetch the issues for the repository. This will delete any issues that have
+   * Refresh the issues for the current repository. This will delete any issues that have
    * been closed and update or add any issues that have changed or been added.
    */
-  public async fetchIssues(repository: GitHubRepository, account: Account) {
+  public async refreshIssues(repository: GitHubRepository, account: Account) {
     const api = API.fromAccount(account)
     const lastUpdatedAt = await this.getLatestUpdatedAt(repository)
 

app/src/lib/stores/pull-request-store.ts

@@ -16,14 +16,7 @@ import {
 import { TypedBaseStore } from './base-store'
 import { Repository } from '../../models/repository'
 import { getRemotes, removeRemote } from '../git'
-import { IRemote } from '../../models/remote'
-
-/**
- * This is the magic remote name prefix
- * for when we add a remote on behalf of
- * the user.
- */
-export const ForkedRemotePrefix = 'github-desktop-'
+import { IRemote, ForkedRemotePrefix } from '../../models/remote'
 
 const Decrement = (n: number) => n - 1
 const Increment = (n: number) => n + 1
@@ -326,22 +319,29 @@ export class PullRequestStore extends TypedBaseStore<GitHubRepository> {
 
     const table = this.pullRequestDatabase.pullRequests
     const prsToInsert = new Array<IPullRequest>()
-    let githubRepo: GitHubRepository | null = null
 
     for (const pr of pullRequestsFromAPI) {
-      // Once the repo is found on first try, no need to keep looking
-      if (githubRepo == null && pr.head.repo != null) {
-        githubRepo = await this.repositoryStore.upsertGitHubRepository(
-          repository.endpoint,
-          pr.head.repo
+      // `pr.head.repo` represents the source of the pull request. It might be
+      // a branch associated with the current repository, or a fork of the
+      // current repository.
+      //
+      // In cases where the user has removed the fork of the repository after
+      // opening a pull request, this can be `null`, and the app will not store
+      // this pull request.
+
+      if (pr.head.repo == null) {
+        log.debug(
+          `Unable to store pull request #${pr.number} for repository ${
+            repository.fullName
+          } as it has no head repository associated with it`
         )
+        continue
       }
 
-      if (githubRepo == null) {
-        return fatalError(
-          "The PR doesn't seem to be associated with a GitHub repository"
-        )
-      }
+      const githubRepo = await this.repositoryStore.upsertGitHubRepository(
+        repository.endpoint,
+        pr.head.repo
+      )
 
       const githubRepoDbId = forceUnwrap(
         'PR cannot have non-existent repo',
@@ -381,16 +381,7 @@ export class PullRequestStore extends TypedBaseStore<GitHubRepository> {
       })
     }
 
-    if (prsToInsert.length <= 0) {
-      return
-    }
-
     return this.pullRequestDatabase.transaction('rw', table, async () => {
-      // since all PRs come from the same repository
-      // using the base repoId of the fist element
-      // is sufficient here
-      const repoDbId = prsToInsert[0].base.repoId!
-
       // we need to delete the stales PRs from the db
       // so we remove all for a repo to avoid having to
       // do diffing
@@ -399,7 +390,9 @@ export class PullRequestStore extends TypedBaseStore<GitHubRepository> {
         .equals(repoDbId)
         .delete()
 
-      await table.bulkAdd(prsToInsert)
+      if (prsToInsert.length > 0) {
+        await table.bulkAdd(prsToInsert)
+      }
     })
   }
 

app/src/lib/stores/repository-settings-store.ts

@@ -49,8 +49,20 @@ export class RepositorySettingsStore extends BaseStore {
   public async saveGitIgnore(text: string): Promise<void> {
     const repository = this._repository
     const ignorePath = Path.join(repository.path, '.gitignore')
-    const fileContents = await formatGitIgnoreContents(text, repository)
 
+    if (text === '') {
+      return new Promise<void>((resolve, reject) => {
+        FS.unlink(ignorePath, err => {
+          if (err) {
+            reject(err)
+          } else {
+            resolve()
+          }
+        })
+      })
+    }
+
+    const fileContents = await formatGitIgnoreContents(text, repository)
     return new Promise<void>((resolve, reject) => {
       FS.writeFile(ignorePath, fileContents, err => {
         if (err) {

app/src/lib/tailer.ts

@@ -31,6 +31,19 @@ export class Tailer {
     return this.emitter.on('data', fn)
   }
 
+  /**
+   * Register a function to be called whenever an error is reported by the underlying
+   * filesystem watcher.
+   */
+  public onError(fn: (error: Error) => void): Disposable {
+    return this.emitter.on('error', fn)
+  }
+
+  private handleError(error: Error) {
+    this.state = null
+    this.emitter.emit('error', error)
+  }
+
   /**
    * Start tailing the file. This can only be called again after calling `stop`.
    */
@@ -43,10 +56,12 @@ export class Tailer {
 
     try {
       const watcher = Fs.watch(this.path, this.onWatchEvent)
+      watcher.on('error', error => {
+        this.handleError(error)
+      })
       this.state = { watcher, position: 0 }
-    } catch (e) {
-      log.debug(`unable to watch path: ${this.path}`, e)
-      this.state = null
+    } catch (error) {
+      this.handleError(error)
     }
   }
 

app/src/lib/text-token-parser.ts

@@ -51,7 +51,7 @@ type LookupResult = {
  */
 export class Tokenizer {
   private readonly emoji: Map<string, string>
-  private readonly repository: GitHubRepository | null
+  private readonly repository: GitHubRepository | null = null
 
   private _results = new Array<TokenResult>()
   private _currentString = ''

app/src/main-process/main.ts

@@ -1,6 +1,6 @@
 import '../lib/logging/main/install'
 
-import { app, Menu, MenuItem, ipcMain, BrowserWindow, shell } from 'electron'
+import { app, Menu, ipcMain, BrowserWindow, shell } from 'electron'
 import * as Fs from 'fs'
 
 import { AppWindow } from './app-window'
@@ -21,6 +21,8 @@ import {
 } from '../lib/source-map-support'
 import { now } from './now'
 import { showUncaughtException } from './show-uncaught-exception'
+import { IMenuItem } from '../lib/menu-item'
+import { buildContextMenu } from './menu/build-context-menu'
 
 enableSourceMaps()
 
@@ -272,20 +274,10 @@ app.on('ready', () => {
 
   ipcMain.on(
     'show-contextual-menu',
-    (event: Electron.IpcMessageEvent, items: ReadonlyArray<any>) => {
-      const menu = new Menu()
-      const menuItems = items.map((item, i) => {
-        return new MenuItem({
-          label: item.label,
-          click: () => event.sender.send('contextual-menu-action', i),
-          type: item.type,
-          enabled: item.enabled,
-        })
-      })
-
-      for (const item of menuItems) {
-        menu.append(item)
-      }
+    (event: Electron.IpcMessageEvent, items: ReadonlyArray<IMenuItem>) => {
+      const menu = buildContextMenu(items, ix =>
+        event.sender.send('contextual-menu-action', ix)
+      )
 
       const window = BrowserWindow.fromWebContents(event.sender)
       menu.popup(window, { async: true })

app/src/main-process/menu/build-context-menu.ts

@@ -0,0 +1,82 @@
+import { IMenuItem } from '../../lib/menu-item'
+import { Menu, MenuItem } from 'electron'
+
+/**
+ * Gets a value indicating whether or not two roles are considered
+ * equal using a case-insensitive comparison.
+ */
+function roleEquals(x: string | undefined, y: string | undefined) {
+  return (x ? x.toLowerCase() : x) === (y ? y.toLowerCase() : y)
+}
+
+/**
+ * Get platform-specific edit menu items by leveraging Electron's
+ * built-in editMenu role.
+ */
+function getEditMenuItems(): ReadonlyArray<MenuItem> {
+  const menu = Menu.buildFromTemplate([{ role: 'editMenu' }]).items[0]
+
+  // Electron is violating its contract if there's no subMenu but
+  // we'd rather just ignore it than crash. It's not the end of
+  // the world if we don't have edit menu items.
+  const items = menu && menu.submenu ? menu.submenu.items : []
+
+  // We don't use styled inputs anywhere at the moment
+  // so let's skip this for now and when/if we do we
+  // can make it configurable from the callee
+  return items.filter(x => !roleEquals(x.role, 'pasteandmatchstyle'))
+}
+
+/**
+ * Create an Electron menu object for use in a context menu based on
+ * a template provided by the renderer.
+ *
+ * If the template contains a menu item with the role 'editMenu' the
+ * platform standard edit menu items will be inserted at the position
+ * of the 'editMenu' template.
+ *
+ * @param template One or more menu item templates as passed from
+ *                 the renderer.
+ * @param onClick  A callback function for when one of the menu items
+ *                 constructed from the template is clicked. Callback
+ *                 is passed the index of the menu item in the template
+ *                 as the first argument and the template item itself
+ *                 as the second argument. Note that the callback will
+ *                 not be called when expanded/automatically created
+ *                 edit menu items are clicked.
+ */
+export function buildContextMenu(
+  template: ReadonlyArray<IMenuItem>,
+  onClick: (ix: number, item: IMenuItem) => void
+): Menu {
+  const menuItems = new Array<MenuItem>()
+
+  for (const [ix, item] of template.entries()) {
+    // Special case editMenu in context menus. What we
+    // mean by this is that we want to insert all edit
+    // related menu items into the menu at this spot, we
+    // don't want a sub menu
+    if (roleEquals(item.role, 'editmenu')) {
+      menuItems.push(...getEditMenuItems())
+    } else {
+      // TODO: We're always overriding the click function here.
+      // It's possible that we might want to add a role-based
+      // menu item without a custom click function at some point
+      // in the future.
+      menuItems.push(
+        new MenuItem({
+          label: item.label,
+          type: item.type,
+          enabled: item.enabled,
+          role: item.role,
+          click: () => onClick(ix, item),
+        })
+      )
+    }
+  }
+
+  const menu = new Menu()
+  menuItems.forEach(x => menu.append(x))
+
+  return menu
+}

app/src/models/account.ts

@@ -6,43 +6,27 @@ import { getDotComAPIEndpoint, IAPIEmail } from '../lib/api'
  * This contains a token that will be used for operations that require authentication.
  */
 export class Account {
-  /** The access token used to perform operations on behalf of this account */
-  public readonly token: string
-  /** The login name for this account  */
-  public readonly login: string
-  /** The server for this account - GitHub or a GitHub Enterprise instance */
-  public readonly endpoint: string
-  /** The current list of email addresses associated with the account */
-  public readonly emails: ReadonlyArray<IAPIEmail>
-  /** The profile URL to render for this account */
-  public readonly avatarURL: string
-  /** The database id for this account */
-  public readonly id: number
-  /** The friendly name associated with this account */
-  public readonly name: string
-
   /** Create an account which can be used to perform unauthenticated API actions */
   public static anonymous(): Account {
     return new Account('', getDotComAPIEndpoint(), '', [], '', -1, '')
   }
 
   public constructor(
-    login: string,
-    endpoint: string,
-    token: string,
-    emails: ReadonlyArray<IAPIEmail>,
-    avatarURL: string,
-    id: number,
-    name: string
-  ) {
-    this.login = login
-    this.endpoint = endpoint
-    this.token = token
-    this.emails = emails
-    this.avatarURL = avatarURL
-    this.id = id
-    this.name = name
-  }
+    /** The login name for this account  */
+    public readonly login: string,
+    /** The server for this account - GitHub or a GitHub Enterprise instance */
+    public readonly endpoint: string,
+    /** The access token used to perform operations on behalf of this account */
+    public readonly token: string,
+    /** The current list of email addresses associated with the account */
+    public readonly emails: ReadonlyArray<IAPIEmail>,
+    /** The profile URL to render for this account */
+    public readonly avatarURL: string,
+    /** The database id for this account */
+    public readonly id: number,
+    /** The friendly name associated with this account */
+    public readonly name: string
+  ) {}
 
   public withToken(token: string): Account {
     return new Account(

app/src/models/commit.ts

@@ -1,14 +1,18 @@
 import { CommitIdentity } from './commit-identity'
-import { ITrailer } from '../lib/git/interpret-trailers'
+import { ITrailer, isCoAuthoredByTrailer } from '../lib/git/interpret-trailers'
 import { GitAuthor } from './git-author'
 import { GitHubRepository } from './github-repository'
 import { getDotComAPIEndpoint } from '../lib/api'
 
+/**
+ * Extract any Co-Authored-By trailers from an array of arbitrary
+ * trailers.
+ */
 function extractCoAuthors(trailers: ReadonlyArray<ITrailer>) {
   const coAuthors = []
 
   for (const trailer of trailers) {
-    if (trailer.token.toLowerCase() === 'co-authored-by') {
+    if (isCoAuthoredByTrailer(trailer)) {
       const author = GitAuthor.parse(trailer.value)
       if (author) {
         coAuthors.push(author)

app/src/models/diff.ts

@@ -19,6 +19,11 @@ export class Image {
    * The data URI media type, so the browser can render the image correctly
    */
   public readonly mediaType: string
+
+  public constructor(contents: string, mediaType: string) {
+    this.contents = contents
+    this.mediaType = mediaType
+  }
 }
 
 /** each diff is made up of a number of hunks */
@@ -46,16 +51,18 @@ export class DiffHunk {
 }
 
 export enum DiffType {
-  /** changes to a text file, which may be partially selected for commit */
+  /** Changes to a text file, which may be partially selected for commit */
   Text,
-  /** changes to files of a known format, which can be viewed in the app */
+  /** Changes to files of a known format, which can be viewed in the app */
   Image,
-  /** changes to an unknown file format, which Git is unable to present in a human-friendly format */
+  /** Changes to an unknown file format, which Git is unable to present in a human-friendly format */
   Binary,
-  /** change to a repository which is included as a submodule of this repository */
+  /** Change to a repository which is included as a submodule of this repository */
   Submodule,
-  /** diff too large to render in app */
-  TooLarge,
+  /** Diff is large enough to degrade ux if rendered */
+  LargeText,
+  /** Diff that will not be rendered */
+  Unrenderable,
 }
 
 /** indicate what a line in the diff represents */
@@ -118,18 +125,27 @@ export interface IBinaryDiff {
   readonly kind: DiffType.Binary
 }
 
-export interface IDiffTooLarge {
-  readonly kind: DiffType.TooLarge
-  /**
-   * The length of the diff output from Git which exceeds the runtime limits:
-   *
-   * 268435441 bytes = 256MB - 15 bytes
-   */
-  readonly length: number
+export interface ILargeTextDiff {
+  readonly kind: DiffType.LargeText
+  /** The unified text diff - including headers and context */
+  readonly text: string
+  /** The diff contents organized by hunk - how the git CLI outputs to the caller */
+  readonly hunks: ReadonlyArray<DiffHunk>
+  /** A warning from Git that the line endings have changed in this file and will affect the commit */
+  readonly lineEndingsChange?: LineEndingsChange
+}
+
+export interface IUnrenderableDiff {
+  readonly kind: DiffType.Unrenderable
 }
 
 /** The union of diff types that can be rendered in Desktop */
-export type IDiff = ITextDiff | IImageDiff | IBinaryDiff | IDiffTooLarge
+export type IDiff =
+  | ITextDiff
+  | IImageDiff
+  | IBinaryDiff
+  | ILargeTextDiff
+  | IUnrenderableDiff
 
 /** track details related to each line in the diff */
 export class DiffLine {

app/src/models/remote.ts

@@ -1,3 +1,10 @@
+/**
+ * This is the magic remote name prefix
+ * for when we add a remote on behalf of
+ * the user.
+ */
+export const ForkedRemotePrefix = 'github-desktop-'
+
 /** A remote as defined in Git. */
 export interface IRemote {
   readonly name: string

app/src/ui/app-menu/menu-pane.tsx

@@ -148,7 +148,7 @@ function createState(props: IMenuPaneProps): IMenuPaneState {
 }
 
 export class MenuPane extends React.Component<IMenuPaneProps, IMenuPaneState> {
-  private list: List | null
+  private list: List | null = null
 
   public constructor(props: IMenuPaneProps) {
     super(props)

app/src/ui/app.tsx

@@ -122,7 +122,7 @@ export class App extends React.Component<IAppProps, IAppState> {
    * modal dialog such as the preferences, or an error dialog.
    */
   private get isShowingModal() {
-    return this.state.currentPopup || this.state.errors.length
+    return this.state.currentPopup !== null || this.state.errors.length > 0
   }
 
   public constructor(props: IAppProps) {
@@ -535,11 +535,24 @@ export class App extends React.Component<IAppProps, IAppState> {
   }
 
   public componentDidMount() {
-    document.ondragover = document.ondrop = e => {
+    document.ondragover = e => {
+      if (this.isShowingModal) {
+        e.dataTransfer.dropEffect = 'none'
+      } else {
+        e.dataTransfer.dropEffect = 'copy'
+      }
+
+      e.preventDefault()
+    }
+
+    document.ondrop = e => {
       e.preventDefault()
     }
 
     document.body.ondrop = e => {
+      if (this.isShowingModal) {
+        return
+      }
       const files = e.dataTransfer.files
       this.handleDragAndDrop(files)
       e.preventDefault()
@@ -867,9 +880,7 @@ export class App extends React.Component<IAppProps, IAppState> {
     )
   }
 
-  private onPopupDismissed = () => {
-    this.props.dispatcher.closePopup()
-  }
+  private onPopupDismissed = () => this.props.dispatcher.closePopup()
 
   private onSignInDialogDismissed = () => {
     this.props.dispatcher.resetSignInState()
@@ -886,9 +897,8 @@ export class App extends React.Component<IAppProps, IAppState> {
     )
   }
 
-  private onUpdateAvailableDismissed = () => {
+  private onUpdateAvailableDismissed = () =>
     this.props.dispatcher.setUpdateBannerVisibility(false)
-  }
 
   private currentPopupContent(): JSX.Element | null {
     // Hide any dialogs while we're displaying an error
@@ -1250,9 +1260,7 @@ export class App extends React.Component<IAppProps, IAppState> {
     this.props.dispatcher.performRetry(retryAction)
   }
 
-  private onCheckForUpdates = () => {
-    this.checkForUpdates(false)
-  }
+  private onCheckForUpdates = () => this.checkForUpdates(false)
 
   private showAcknowledgements = () => {
     this.props.dispatcher.showPopup({ type: PopupType.Acknowledgements })
@@ -1283,9 +1291,7 @@ export class App extends React.Component<IAppProps, IAppState> {
     return <FullScreenInfo windowState={this.state.windowState} />
   }
 
-  private clearError = (error: Error) => {
-    this.props.dispatcher.clearError(error)
-  }
+  private clearError = (error: Error) => this.props.dispatcher.clearError(error)
 
   private onConfirmDiscardChangesChanged = (value: boolean) => {
     this.props.dispatcher.setConfirmDiscardChangesSetting(value)
@@ -1332,7 +1338,6 @@ export class App extends React.Component<IAppProps, IAppState> {
         onSelectionChanged={this.onSelectionChanged}
         repositories={this.state.repositories}
         onRemoveRepository={this.removeRepository}
-        onClose={this.onCloseRepositoryList}
         onOpenInShell={this.openInShell}
         onShowRepository={this.showRepository}
         onOpenInExternalEditor={this.openInExternalEditor}
@@ -1350,6 +1355,10 @@ export class App extends React.Component<IAppProps, IAppState> {
     this.props.dispatcher.openShell(repository.path)
   }
 
+  private openFileInExternalEditor = (path: string) => {
+    this.props.dispatcher.openInExternalEditor(path)
+  }
+
   private openInExternalEditor = (
     repository: Repository | CloningRepository
   ) => {
@@ -1368,10 +1377,6 @@ export class App extends React.Component<IAppProps, IAppState> {
     shell.showItemInFolder(repository.path)
   }
 
-  private onCloseRepositoryList = () => {
-    this.props.dispatcher.closeFoldout(FoldoutType.Repository)
-  }
-
   private onRepositoryDropdownStateChanged = (newState: DropdownState) => {
     if (newState === 'open') {
       this.props.dispatcher.showFoldout({ type: FoldoutType.Repository })
@@ -1390,9 +1395,12 @@ export class App extends React.Component<IAppProps, IAppState> {
     if (repository) {
       icon = iconForRepository(repository)
       title = repository.name
-    } else {
+    } else if (this.state.repositories.length > 0) {
       icon = OcticonSymbol.repo
       title = __DARWIN__ ? 'Select a Repository' : 'Select a repository'
+    } else {
+      icon = OcticonSymbol.repo
+      title = __DARWIN__ ? 'No Repositories' : 'No repositories'
     }
 
     const isOpen =
@@ -1586,6 +1594,8 @@ export class App extends React.Component<IAppProps, IAppState> {
     }
 
     if (selectedState.type === SelectionType.Repository) {
+      const externalEditorLabel = this.state.selectedExternalEditor
+
       return (
         <RepositoryView
           repository={selectedState.repository}
@@ -1602,6 +1612,8 @@ export class App extends React.Component<IAppProps, IAppState> {
             this.state.askForConfirmationOnDiscardChanges
           }
           accounts={this.state.accounts}
+          externalEditorLabel={externalEditorLabel}
+          onOpenInExternalEditor={this.openFileInExternalEditor}
         />
       )
     } else if (selectedState.type === SelectionType.CloningRepository) {

app/src/ui/autocompletion/autocompleting-text-input.tsx

@@ -10,6 +10,7 @@ interface IRange {
 }
 
 import getCaretCoordinates = require('textarea-caret')
+import { showContextualMenu } from '../main-process-proxy'
 
 interface IAutocompletingTextInputProps<ElementType> {
   /**
@@ -24,6 +25,9 @@ interface IAutocompletingTextInputProps<ElementType> {
   /** The current value of the input field. */
   readonly value?: string
 
+  /** Disabled state for input field. */
+  readonly disabled?: boolean
+
   /**
    * Called when the user changes the value in the input field.
    */
@@ -43,6 +47,12 @@ interface IAutocompletingTextInputProps<ElementType> {
    * is mounted or unmounted.
    */
   readonly onElementRef?: (elem: ElementType | null) => void
+
+  /**
+   * Optional callback to override the default edit context menu
+   * in the input field.
+   */
+  readonly onContextMenu?: (event: React.MouseEvent<any>) => void
 }
 
 interface IAutocompletionState<T> {
@@ -197,7 +207,7 @@ export abstract class AutocompletingTextInput<
     const item = currentAutoCompletionState.items[row]
 
     if (item) {
-      this.insertCompletion(item)
+      this.insertCompletion(item, 'mouseclick')
     }
   }
 
@@ -231,16 +241,7 @@ export abstract class AutocompletingTextInput<
 
     const item = items[row]
 
-    this.insertCompletion(item)
-
-    // This is pretty gross. Clicking on the list moves focus off the text area.
-    // Immediately moving focus back doesn't work. Gotta wait a runloop I guess?
-    window.setTimeout(() => {
-      const element = this.element
-      if (element) {
-        element.focus()
-      }
-    }, 0)
+    this.insertCompletion(item, 'mouseclick')
   }
 
   /**
@@ -249,6 +250,15 @@ export abstract class AutocompletingTextInput<
    */
   protected abstract getElementTagName(): 'textarea' | 'input'
 
+  private onContextMenu = (event: React.MouseEvent<any>) => {
+    if (this.props.onContextMenu) {
+      this.props.onContextMenu(event)
+    } else {
+      event.preventDefault()
+      showContextualMenu([{ role: 'editMenu' }])
+    }
+  }
+
   private renderTextInput() {
     const props = {
       type: 'text',
@@ -258,6 +268,8 @@ export abstract class AutocompletingTextInput<
       onChange: this.onChange,
       onKeyDown: this.onKeyDown,
       onBlur: this.onBlur,
+      onContextMenu: this.onContextMenu,
+      disabled: this.props.disabled,
     }
 
     return React.createElement<React.HTMLAttributes<ElementType>, ElementType>(
@@ -302,7 +314,17 @@ export abstract class AutocompletingTextInput<
     )
   }
 
-  private insertCompletion(item: Object) {
+  private setCursorPosition(newCaretPosition: number) {
+    if (this.element == null) {
+      log.warn('Unable to set cursor position when element is null')
+      return
+    }
+
+    this.element.selectionStart = newCaretPosition
+    this.element.selectionEnd = newCaretPosition
+  }
+
+  private insertCompletion(item: Object, source: 'mouseclick' | 'keyboard') {
     const element = this.element!
     const autocompletionState = this.state.autocompletionState!
     const originalText = element.value
@@ -310,17 +332,32 @@ export abstract class AutocompletingTextInput<
     const autoCompleteText = autocompletionState.provider.getCompletionText(
       item
     )
+
+    const textWithAutoCompleteText =
+      originalText.substr(0, range.start - 1) + autoCompleteText + ' '
+
     const newText =
-      originalText.substr(0, range.start - 1) +
-      autoCompleteText +
-      originalText.substr(range.start + range.length) +
-      ' '
+      textWithAutoCompleteText + originalText.substr(range.start + range.length)
+
     element.value = newText
 
     if (this.props.onValueChanged) {
       this.props.onValueChanged(newText)
     }
 
+    const newCaretPosition = textWithAutoCompleteText.length
+
+    if (source === 'mouseclick') {
+      // we only need to re-focus on the text input when the autocomplete overlay
+      // steals focus due to the user clicking on a selection in the autocomplete list
+      window.setTimeout(() => {
+        element.focus()
+        this.setCursorPosition(newCaretPosition)
+      }, 0)
+    } else {
+      this.setCursorPosition(newCaretPosition)
+    }
+
     this.close()
   }
 
@@ -385,7 +422,7 @@ export abstract class AutocompletingTextInput<
       if (item) {
         event.preventDefault()
 
-        this.insertCompletion(item)
+        this.insertCompletion(item, 'keyboard')
       }
     } else if (event.key === 'Escape') {
       this.close()
@@ -435,7 +472,18 @@ export abstract class AutocompletingTextInput<
       this.props.onValueChanged(str)
     }
 
-    const caretPosition = this.element!.selectionStart
+    const element = this.element
+
+    if (element === null) {
+      return
+    }
+
+    const caretPosition = element.selectionStart
+
+    if (caretPosition === null) {
+      return
+    }
+
     const requestID = ++this.autocompletionRequestID
     const autocompletionState = await this.attemptAutocompletion(
       str,

app/src/ui/autocompletion/issues-autocompletion-provider.tsx

@@ -52,7 +52,7 @@ export class IssuesAutocompletionProvider
     text: string
   ): Promise<ReadonlyArray<IIssueHit>> {
     this.updateIssuesScheduler.queue(() => {
-      this.dispatcher.updateIssues(this.repository)
+      this.dispatcher.refreshIssues(this.repository)
     })
 
     return this.issuesStore.getIssuesMatching(this.repository, text)

app/src/ui/branches/branch-list.tsx

@@ -212,11 +212,11 @@ export class BranchList extends React.Component<
         rowHeight={RowHeight}
         filterText={this.props.filterText}
         onFilterTextChanged={this.props.onFilterTextChanged}
+        onFilterKeyDown={this.props.onFilterKeyDown}
         selectedItem={this.state.selectedItem}
         renderItem={this.renderItem}
         renderGroupHeader={this.renderGroupHeader}
         onItemClick={this.onItemClick}
-        onFilterKeyDown={this.props.onFilterKeyDown}
         onSelectionChanged={this.onSelectionChanged}
         groups={this.state.groups}
         invalidationProps={this.props.allBranches}
@@ -239,7 +239,7 @@ export class BranchList extends React.Component<
     if (this.props.canCreateNewBranch) {
       return (
         <Button className="new-branch-button" onClick={this.onCreateNewBranch}>
-          New
+          {__DARWIN__ ? 'New Branch' : 'New branch'}
         </Button>
       )
     } else {

app/src/ui/branches/branches-container.tsx

@@ -7,24 +7,22 @@ import { BranchList } from './branch-list'
 import { TabBar } from '../tab-bar'
 import { BranchesTab } from '../../models/branches-tab'
 import { assertNever } from '../../lib/fatal-error'
-import { enablePRIntegration } from '../../lib/feature-flag'
 import { PullRequestList } from './pull-request-list'
 import { PullRequestsLoading } from './pull-requests-loading'
-import { NoPullRequests } from './no-pull-requests'
 import { PullRequest } from '../../models/pull-request'
 import { CSSTransitionGroup } from 'react-transition-group'
 
 const PullRequestsLoadingCrossFadeInTimeout = 300
 const PullRequestsLoadingCrossFadeOutTimeout = 200
 
-interface IBranchesProps {
-  readonly defaultBranch: Branch | null
-  readonly currentBranch: Branch | null
-  readonly allBranches: ReadonlyArray<Branch>
-  readonly recentBranches: ReadonlyArray<Branch>
+interface IBranchesContainerProps {
   readonly dispatcher: Dispatcher
   readonly repository: Repository
   readonly selectedTab: BranchesTab
+  readonly allBranches: ReadonlyArray<Branch>
+  readonly defaultBranch: Branch | null
+  readonly currentBranch: Branch | null
+  readonly recentBranches: ReadonlyArray<Branch>
   readonly pullRequests: ReadonlyArray<PullRequest>
 
   /** The pull request associated with the current branch. */
@@ -34,58 +32,36 @@ interface IBranchesProps {
   readonly isLoadingPullRequests: boolean
 }
 
-interface IBranchesState {
+interface IBranchesContainerState {
   readonly selectedBranch: Branch | null
   readonly selectedPullRequest: PullRequest | null
-  readonly filterText: string
+  readonly branchFilterText: string
+  readonly pullRequestFilterText: string
 }
 
 /** The unified Branches and Pull Requests component. */
 export class BranchesContainer extends React.Component<
-  IBranchesProps,
-  IBranchesState
+  IBranchesContainerProps,
+  IBranchesContainerState
 > {
-  public constructor(props: IBranchesProps) {
+  public constructor(props: IBranchesContainerProps) {
     super(props)
 
     this.state = {
       selectedBranch: props.currentBranch,
       selectedPullRequest: props.currentPullRequest,
-      filterText: '',
+      branchFilterText: '',
+      pullRequestFilterText: '',
     }
   }
 
-  private onItemClick = (branch: Branch) => {
-    this.props.dispatcher.closeFoldout(FoldoutType.Branch)
-
-    const currentBranch = this.props.currentBranch
-
-    if (currentBranch == null || currentBranch.name !== branch.name) {
-      this.props.dispatcher.checkoutBranch(this.props.repository, branch)
-    }
-  }
-
-  private onFilterKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      if (this.state.filterText.length === 0) {
-        this.props.dispatcher.closeFoldout(FoldoutType.Branch)
-        event.preventDefault()
-      }
-    }
-  }
-
-  private onFilterTextChanged = (filterText: string) => {
-    this.setState({ filterText })
-  }
-
-  private onBranchSelectionChanged = (selectedBranch: Branch | null) => {
-    this.setState({ selectedBranch })
-  }
-
-  private onPullRequestSelectionChanged = (
-    selectedPullRequest: PullRequest | null
-  ) => {
-    this.setState({ selectedPullRequest })
+  public render() {
+    return (
+      <div className="branches-container">
+        {this.renderTabBar()}
+        {this.renderSelectedTab()}
+      </div>
+    )
   }
 
   private renderTabBar() {
@@ -93,10 +69,6 @@ export class BranchesContainer extends React.Component<
       return null
     }
 
-    if (!enablePRIntegration()) {
-      return null
-    }
-
     let countElement = null
     if (this.props.pullRequests) {
       countElement = (
@@ -121,7 +93,7 @@ export class BranchesContainer extends React.Component<
 
   private renderSelectedTab() {
     let tab = this.props.selectedTab
-    if (!enablePRIntegration() || !this.props.repository.gitHubRepository) {
+    if (!this.props.repository.gitHubRepository) {
       tab = BranchesTab.Branches
     }
 
@@ -133,10 +105,9 @@ export class BranchesContainer extends React.Component<
             currentBranch={this.props.currentBranch}
             allBranches={this.props.allBranches}
             recentBranches={this.props.recentBranches}
-            onItemClick={this.onItemClick}
-            filterText={this.state.filterText}
-            onFilterKeyDown={this.onFilterKeyDown}
-            onFilterTextChanged={this.onFilterTextChanged}
+            onItemClick={this.onBranchItemClick}
+            filterText={this.state.branchFilterText}
+            onFilterTextChanged={this.onBranchFilterTextChanged}
             selectedBranch={this.state.selectedBranch}
             onSelectionChanged={this.onBranchSelectionChanged}
             canCreateNewBranch={true}
@@ -163,48 +134,62 @@ export class BranchesContainer extends React.Component<
   }
 
   private renderPullRequests() {
-    const pullRequests = this.props.pullRequests
-    if (pullRequests.length) {
-      return (
-        <PullRequestList
-          key="pr-list"
-          pullRequests={pullRequests}
-          onSelectionChanged={this.onPullRequestSelectionChanged}
-          selectedPullRequest={this.state.selectedPullRequest}
-          onItemClick={this.onPullRequestClicked}
-          onDismiss={this.onDismiss}
-        />
-      )
-    } else if (this.props.isLoadingPullRequests) {
+    if (this.props.isLoadingPullRequests) {
       return <PullRequestsLoading key="prs-loading" />
-    } else {
-      const repo = this.props.repository
-      const name = repo.gitHubRepository
-        ? repo.gitHubRepository.fullName
-        : repo.name
-      const isOnDefaultBranch =
-        this.props.defaultBranch &&
-        this.props.currentBranch &&
-        this.props.defaultBranch.name === this.props.currentBranch.name
-      return (
-        <NoPullRequests
-          key="no-prs"
-          repositoryName={name}
-          isOnDefaultBranch={!!isOnDefaultBranch}
-          onCreateBranch={this.onCreateBranch}
-          onCreatePullRequest={this.onCreatePullRequest}
-        />
-      )
+    }
+
+    const pullRequests = this.props.pullRequests
+    const repo = this.props.repository
+    const name = repo.gitHubRepository
+      ? repo.gitHubRepository.fullName
+      : repo.name
+    const isOnDefaultBranch =
+      this.props.defaultBranch &&
+      this.props.currentBranch &&
+      this.props.defaultBranch.name === this.props.currentBranch.name
+
+    return (
+      <PullRequestList
+        key="pr-list"
+        pullRequests={pullRequests}
+        selectedPullRequest={this.state.selectedPullRequest}
+        repositoryName={name}
+        isOnDefaultBranch={!!isOnDefaultBranch}
+        onSelectionChanged={this.onPullRequestSelectionChanged}
+        onCreateBranch={this.onCreateBranch}
+        onCreatePullRequest={this.onCreatePullRequest}
+        filterText={this.state.pullRequestFilterText}
+        onFilterTextChanged={this.onPullRequestFilterTextChanged}
+        onItemClick={this.onPullRequestClicked}
+        onDismiss={this.onDismiss}
+      />
+    )
+  }
+
+  private onTabClicked = (tab: BranchesTab) => {
+    this.props.dispatcher.changeBranchesTab(tab)
+  }
+
+  private onDismiss = () => {
+    this.props.dispatcher.closeFoldout(FoldoutType.Branch)
+  }
+
+  private onBranchItemClick = (branch: Branch) => {
+    this.props.dispatcher.closeFoldout(FoldoutType.Branch)
+
+    const currentBranch = this.props.currentBranch
+
+    if (currentBranch == null || currentBranch.name !== branch.name) {
+      this.props.dispatcher.checkoutBranch(this.props.repository, branch)
     }
   }
 
-  public render() {
-    return (
-      <div className="branches-container">
-        {this.renderTabBar()}
-        {this.renderSelectedTab()}
-      </div>
-    )
+  private onBranchSelectionChanged = (selectedBranch: Branch | null) => {
+    this.setState({ selectedBranch })
+  }
+
+  private onBranchFilterTextChanged = (text: string) => {
+    this.setState({ branchFilterText: text })
   }
 
   private onCreateBranchWithName = (name: string) => {
@@ -220,15 +205,21 @@ export class BranchesContainer extends React.Component<
     this.onCreateBranchWithName('')
   }
 
+  private onPullRequestFilterTextChanged = (text: string) => {
+    this.setState({ pullRequestFilterText: text })
+  }
+
+  private onPullRequestSelectionChanged = (
+    selectedPullRequest: PullRequest | null
+  ) => {
+    this.setState({ selectedPullRequest })
+  }
+
   private onCreatePullRequest = () => {
     this.props.dispatcher.closeFoldout(FoldoutType.Branch)
     this.props.dispatcher.createPullRequest(this.props.repository)
   }
 
-  private onTabClicked = (tab: BranchesTab) => {
-    this.props.dispatcher.changeBranchesTab(tab)
-  }
-
   private onPullRequestClicked = (pullRequest: PullRequest) => {
     this.props.dispatcher.closeFoldout(FoldoutType.Branch)
     this.props.dispatcher.checkoutPullRequest(
@@ -238,8 +229,4 @@ export class BranchesContainer extends React.Component<
 
     this.onPullRequestSelectionChanged(pullRequest)
   }
-
-  private onDismiss = () => {
-    this.props.dispatcher.closeFoldout(FoldoutType.Branch)
-  }
 }

app/src/ui/branches/no-pull-requests.tsx

@@ -15,6 +15,9 @@ interface INoPullRequestsProps {
   /** Is the default branch currently checked out? */
   readonly isOnDefaultBranch: boolean
 
+  /** Is this component being rendered due to a search? */
+  readonly isSearch: boolean
+
   /* Called when the user wants to create a new branch. */
   readonly onCreateBranch: () => void
 
@@ -28,18 +31,27 @@ export class NoPullRequests extends React.Component<INoPullRequestsProps, {}> {
     return (
       <div className="no-pull-requests">
         <img src={BlankSlateImage} className="blankslate-image" />
-
-        <div className="title">You're all set!</div>
-
-        <div className="no-prs">
-          No open pull requests in <Ref>{this.props.repositoryName}</Ref>
-        </div>
-
+        {this.renderTitle()}
         {this.renderCallToAction()}
       </div>
     )
   }
 
+  private renderTitle() {
+    if (this.props.isSearch) {
+      return <div className="title">Sorry, I can't find that pull request!</div>
+    } else {
+      return (
+        <div>
+          <div className="title">You're all set!</div>
+          <div className="no-prs">
+            No open pull requests in <Ref>{this.props.repositoryName}</Ref>
+          </div>
+        </div>
+      )
+    }
+  }
+
   private renderCallToAction() {
     if (this.props.isOnDefaultBranch) {
       return (

app/src/ui/branches/pull-request-list.tsx

@@ -7,6 +7,7 @@ import {
 } from '../lib/filter-list'
 import { PullRequestListItem } from './pull-request-list-item'
 import { PullRequest, PullRequestStatus } from '../../models/pull-request'
+import { NoPullRequests } from './no-pull-requests'
 
 interface IPullRequestListItem extends IFilterListItem {
   readonly id: string
@@ -28,23 +29,50 @@ interface IPullRequestListProps {
   /** The pull requests to display. */
   readonly pullRequests: ReadonlyArray<PullRequest>
 
+  /** The currently selected pull request */
+  readonly selectedPullRequest: PullRequest | null
+
+  /** The name of the repository. */
+  readonly repositoryName: string
+
+  /** Is the default branch currently checked out? */
+  readonly isOnDefaultBranch: boolean
+
+  /** The current filter text to render */
+  readonly filterText: string
+
   /** Called when the user clicks on a pull request. */
   readonly onItemClick: (pullRequest: PullRequest) => void
 
   /** Called when the user wants to dismiss the foldout. */
   readonly onDismiss: () => void
 
-  readonly selectedPullRequest: PullRequest | null
+  /** Callback to fire when the filter text is changed */
+  readonly onFilterTextChanged: (filterText: string) => void
 
+  /** Called when the user opts to create a branch */
+  readonly onCreateBranch: () => void
+
+  /** Called when the user opts to create a pull request */
+  readonly onCreatePullRequest: () => void
+
+  /** Callback fired when user selects a new pull request */
   readonly onSelectionChanged?: (
     pullRequest: PullRequest | null,
     source: SelectionSource
   ) => void
+
+  /**
+   * Called when a key down happens in the filter field. Users have a chance to
+   * respond or cancel the default behavior by calling `preventDefault`.
+   */
+  readonly onFilterKeyDown?: (
+    event: React.KeyboardEvent<HTMLInputElement>
+  ) => void
 }
 
 interface IPullRequestListState {
   readonly groupedItems: ReadonlyArray<IFilterListGroup<IPullRequestListItem>>
-  readonly filterText: string
   readonly selectedItem: IPullRequestListItem | null
 }
 
@@ -82,7 +110,6 @@ export class PullRequestList extends React.Component<
 
     this.state = {
       groupedItems: [group],
-      filterText: '',
       selectedItem,
     }
   }
@@ -105,12 +132,25 @@ export class PullRequestList extends React.Component<
         groups={this.state.groupedItems}
         selectedItem={this.state.selectedItem}
         renderItem={this.renderPullRequest}
-        filterText={this.state.filterText}
-        onFilterTextChanged={this.onFilterTextChanged}
+        filterText={this.props.filterText}
+        onFilterTextChanged={this.props.onFilterTextChanged}
         invalidationProps={this.props.pullRequests}
         onItemClick={this.onItemClick}
         onSelectionChanged={this.onSelectionChanged}
-        onFilterKeyDown={this.onFilterKeyDown}
+        onFilterKeyDown={this.props.onFilterKeyDown}
+        renderNoItems={this.renderNoItems}
+      />
+    )
+  }
+
+  private renderNoItems = () => {
+    return (
+      <NoPullRequests
+        isSearch={this.props.filterText.length > 0}
+        repositoryName={this.props.repositoryName}
+        isOnDefaultBranch={this.props.isOnDefaultBranch}
+        onCreateBranch={this.props.onCreateBranch}
+        onCreatePullRequest={this.props.onCreatePullRequest}
       />
     )
   }
@@ -144,10 +184,6 @@ export class PullRequestList extends React.Component<
     )
   }
 
-  private onFilterTextChanged = (filterText: string) => {
-    this.setState({ filterText })
-  }
-
   private onItemClick = (item: IPullRequestListItem) => {
     if (this.props.onItemClick) {
       this.props.onItemClick(item.pullRequest)
@@ -165,15 +201,6 @@ export class PullRequestList extends React.Component<
       )
     }
   }
-
-  private onFilterKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      if (this.state.filterText.length === 0) {
-        this.props.onDismiss()
-        event.preventDefault()
-      }
-    }
-  }
 }
 
 function createListItems(

app/src/ui/changes/changed-file.tsx

@@ -1,37 +1,24 @@
 import * as React from 'react'
-import * as Path from 'path'
 
 import { AppFileStatus, mapStatus, iconForStatus } from '../../models/status'
 import { PathLabel } from '../lib/path-label'
 import { Octicon } from '../octicons'
-import { showContextualMenu, IMenuItem } from '../main-process-proxy'
 import { Checkbox, CheckboxValue } from '../lib/checkbox'
 
-const GitIgnoreFileName = '.gitignore'
-
-const RestrictedFileExtensions = ['.cmd', '.exe', '.bat', '.sh']
-
 interface IChangedFileProps {
   readonly path: string
   readonly status: AppFileStatus
   readonly oldPath?: string
   readonly include: boolean | null
-  readonly onIncludeChanged: (path: string, include: boolean) => void
-  readonly onDiscardChanges: (path: string) => void
-
-  /**
-   * Called to reveal a file in the native file manager.
-   * @param path The path of the file relative to the root of the repository
-   */
-  readonly onRevealInFileManager: (path: string) => void
-
-  /**
-   * Called to open a file it its default application
-   * @param path The path of the file relative to the root of the repository
-   */
-  readonly onOpenItem: (path: string) => void
   readonly availableWidth: number
-  readonly onIgnore: (pattern: string) => void
+  readonly onIncludeChanged: (path: string, include: boolean) => void
+
+  /** Callback called when user right-clicks on an item */
+  readonly onContextMenu: (
+    path: string,
+    status: AppFileStatus,
+    event: React.MouseEvent<any>
+  ) => void
 }
 
 /** a changed file in the working directory for a given repository */
@@ -94,58 +81,7 @@ export class ChangedFile extends React.Component<IChangedFileProps, {}> {
     )
   }
 
-  private onContextMenu = (event: React.MouseEvent<any>) => {
-    event.preventDefault()
-
-    const extension = Path.extname(this.props.path)
-    const fileName = Path.basename(this.props.path)
-    const items: IMenuItem[] = [
-      {
-        label: __DARWIN__ ? 'Discard Changes…' : 'Discard changes…',
-        action: () => this.props.onDiscardChanges(this.props.path),
-      },
-      { type: 'separator' },
-      {
-        label: 'Ignore',
-        action: () => this.props.onIgnore(this.props.path),
-        enabled: fileName !== GitIgnoreFileName,
-      },
-    ]
-
-    if (extension.length) {
-      items.push({
-        label: __DARWIN__
-          ? `Ignore All ${extension} Files`
-          : `Ignore all ${extension} files`,
-        action: () => this.props.onIgnore(`*${extension}`),
-        enabled: fileName !== GitIgnoreFileName,
-      })
-    }
-
-    const isSafeExtension = __WIN32__
-      ? RestrictedFileExtensions.indexOf(extension.toLowerCase()) === -1
-      : true
-
-    const revealInFileManagerLabel = __DARWIN__
-      ? 'Reveal in Finder'
-      : __WIN32__ ? 'Show in Explorer' : 'Show in your File Manager'
-
-    items.push(
-      { type: 'separator' },
-      {
-        label: revealInFileManagerLabel,
-        action: () => this.props.onRevealInFileManager(this.props.path),
-        enabled: this.props.status !== AppFileStatus.Deleted,
-      },
-      {
-        label: __DARWIN__
-          ? 'Open with Default Program'
-          : 'Open with default program',
-        action: () => this.props.onOpenItem(this.props.path),
-        enabled: isSafeExtension && this.props.status !== AppFileStatus.Deleted,
-      }
-    )
-
-    showContextualMenu(items)
+  private onContextMenu = (event: React.MouseEvent<HTMLDivElement>) => {
+    this.props.onContextMenu(this.props.path, this.props.status, event)
   }
 }

app/src/ui/changes/changes-list.tsx

@@ -1,11 +1,13 @@
 import * as React from 'react'
+import * as Path from 'path'
+
 import { CommitMessage } from './commit-message'
 import { ChangedFile } from './changed-file'
 import { List, ClickSource } from '../lib/list'
-
 import {
   WorkingDirectoryStatus,
   WorkingDirectoryFileChange,
+  AppFileStatus,
 } from '../../models/status'
 import { DiffSelectionType } from '../../models/diff'
 import { CommitIdentity } from '../../models/commit-identity'
@@ -15,11 +17,17 @@ import { IGitHubUser } from '../../lib/databases'
 import { Dispatcher } from '../../lib/dispatcher'
 import { IAutocompletionProvider } from '../autocompletion'
 import { Repository } from '../../models/repository'
-import { showContextualMenu, IMenuItem } from '../main-process-proxy'
+import { showContextualMenu } from '../main-process-proxy'
 import { IAuthor } from '../../models/author'
 import { ITrailer } from '../../lib/git/interpret-trailers'
+import { IMenuItem } from '../../lib/menu-item'
 
 const RowHeight = 29
+const RestrictedFileExtensions = ['.cmd', '.exe', '.bat', '.sh']
+const defaultEditorLabel = __DARWIN__
+  ? 'Open in External Editor'
+  : 'Open in external editor'
+const GitIgnoreFileName = '.gitignore'
 
 interface IChangesListProps {
   readonly repository: Repository
@@ -85,6 +93,15 @@ interface IChangesListProps {
    * the user has chosen to do so.
    */
   readonly coAuthors: ReadonlyArray<IAuthor>
+
+  /** The name of the currently selected external editor */
+  readonly externalEditorLabel?: string
+
+  /**
+   * Called to open a file using the user's configured applications
+   * @param path The path of the file relative to the root of the repository
+   */
+  readonly onOpenInExternalEditor: (path: string) => void
 }
 
 export class ChangesList extends React.Component<IChangesListProps, {}> {
@@ -110,11 +127,8 @@ export class ChangesList extends React.Component<IChangesListProps, {}> {
         include={includeAll}
         key={file.id}
         onIncludeChanged={this.props.onIncludeChanged}
-        onDiscardChanges={this.onDiscardChanges}
-        onRevealInFileManager={this.props.onRevealInFileManager}
-        onOpenItem={this.props.onOpenItem}
         availableWidth={this.props.availableWidth}
-        onIgnore={this.props.onIgnore}
+        onContextMenu={this.onItemContextMenu}
       />
     )
   }
@@ -158,6 +172,75 @@ export class ChangesList extends React.Component<IChangesListProps, {}> {
     showContextualMenu(items)
   }
 
+  private onItemContextMenu = (
+    path: string,
+    status: AppFileStatus,
+    event: React.MouseEvent<any>
+  ) => {
+    event.preventDefault()
+
+    const extension = Path.extname(path)
+    const fileName = Path.basename(path)
+    const isSafeExtension = __WIN32__
+      ? RestrictedFileExtensions.indexOf(extension.toLowerCase()) === -1
+      : true
+    const revealInFileManagerLabel = __DARWIN__
+      ? 'Reveal in Finder'
+      : __WIN32__ ? 'Show in Explorer' : 'Show in your File Manager'
+    const openInExternalEditor = this.props.externalEditorLabel
+      ? `Open in ${this.props.externalEditorLabel}`
+      : defaultEditorLabel
+    const items: IMenuItem[] = [
+      {
+        label: __DARWIN__ ? 'Discard Changes…' : 'Discard changes…',
+        action: () => this.onDiscardChanges(path),
+      },
+      {
+        label: __DARWIN__ ? 'Discard All Changes…' : 'Discard all changes…',
+        action: () => this.onDiscardAllChanges(),
+      },
+      { type: 'separator' },
+      {
+        label: 'Ignore',
+        action: () => this.props.onIgnore(path),
+        enabled: fileName !== GitIgnoreFileName,
+      },
+    ]
+
+    if (extension.length) {
+      items.push({
+        label: __DARWIN__
+          ? `Ignore All ${extension} Files`
+          : `Ignore all ${extension} files`,
+        action: () => this.props.onIgnore(`*${extension}`),
+        enabled: fileName !== GitIgnoreFileName,
+      })
+    }
+
+    items.push(
+      { type: 'separator' },
+      {
+        label: revealInFileManagerLabel,
+        action: () => this.props.onRevealInFileManager(path),
+        enabled: status !== AppFileStatus.Deleted,
+      },
+      {
+        label: openInExternalEditor,
+        action: () => this.props.onOpenInExternalEditor(path),
+        enabled: isSafeExtension && status !== AppFileStatus.Deleted,
+      },
+      {
+        label: __DARWIN__
+          ? 'Open with Default Program'
+          : 'Open with default program',
+        action: () => this.props.onOpenItem(path),
+        enabled: isSafeExtension && status !== AppFileStatus.Deleted,
+      }
+    )
+
+    showContextualMenu(items)
+  }
+
   public render() {
     const fileList = this.props.workingDirectory.files
     const selectedRow = fileList.findIndex(

app/src/ui/changes/commit-message.tsx

@@ -18,10 +18,11 @@ import { structuralEquals } from '../../lib/equality'
 import { generateGravatarUrl } from '../../lib/gravatar'
 import { AuthorInput } from '../lib/author-input'
 import { FocusContainer } from '../lib/focus-container'
-import { showContextualMenu, IMenuItem } from '../main-process-proxy'
+import { showContextualMenu } from '../main-process-proxy'
 import { Octicon, OcticonSymbol } from '../octicons'
 import { ITrailer } from '../../lib/git/interpret-trailers'
 import { IAuthor } from '../../models/author'
+import { IMenuItem } from '../../lib/menu-item'
 
 const addAuthorIcon = new OcticonSymbol(
   12,
@@ -328,6 +329,7 @@ export class CommitMessage extends React.Component<
         onAuthorsUpdated={this.onCoAuthorsUpdated}
         authors={this.props.coAuthors}
         autoCompleteProvider={autocompletionProvider}
+        disabled={this.props.isCommitting}
       />
     )
   }
@@ -345,22 +347,41 @@ export class CommitMessage extends React.Component<
       : __DARWIN__ ? 'Add Co-Authors' : 'Add co-authors'
   }
 
+  private getAddRemoveCoAuthorsMenuItem(): IMenuItem {
+    return {
+      label: this.toggleCoAuthorsText,
+      action: this.onToggleCoAuthors,
+      enabled:
+        this.props.repository.gitHubRepository !== null &&
+        !this.props.isCommitting,
+    }
+  }
+
   private onContextMenu = (event: React.MouseEvent<any>) => {
+    if (event.defaultPrevented) {
+      return
+    }
+
+    event.preventDefault()
+
+    const items: IMenuItem[] = [this.getAddRemoveCoAuthorsMenuItem()]
+    showContextualMenu(items)
+  }
+
+  private onAutocompletingInputContextMenu = (event: React.MouseEvent<any>) => {
     event.preventDefault()
 
     const items: IMenuItem[] = [
-      {
-        label: this.toggleCoAuthorsText,
-        action: this.onToggleCoAuthors,
-        enabled: this.props.repository.gitHubRepository !== null,
-      },
+      this.getAddRemoveCoAuthorsMenuItem(),
+      { type: 'separator' },
+      { role: 'editMenu' },
     ]
 
     showContextualMenu(items)
   }
 
   private onCoAuthorToggleButtonClick = (
-    e: React.MouseEvent<HTMLDivElement>
+    e: React.MouseEvent<HTMLButtonElement>
   ) => {
     e.preventDefault()
     this.onToggleCoAuthors()
@@ -372,15 +393,15 @@ export class CommitMessage extends React.Component<
     }
 
     return (
-      <div
-        role="button"
+      <button
         className="co-authors-toggle"
         onClick={this.onCoAuthorToggleButtonClick}
         tabIndex={-1}
         aria-label={this.toggleCoAuthorsText}
+        disabled={this.props.isCommitting}
       >
         <Octicon symbol={addAuthorIcon} />
-      </div>
+      </button>
     )
   }
 
@@ -436,7 +457,11 @@ export class CommitMessage extends React.Component<
       return null
     }
 
-    return <div className="action-bar">{this.renderCoAuthorToggleButton()}</div>
+    const className = classNames('action-bar', {
+      disabled: this.props.isCommitting,
+    })
+
+    return <div className={className}>{this.renderCoAuthorToggleButton()}</div>
   }
 
   public render() {
@@ -471,6 +496,8 @@ export class CommitMessage extends React.Component<
             value={this.state.summary}
             onValueChanged={this.onSummaryChanged}
             autocompletionProviders={this.props.autocompletionProviders}
+            onContextMenu={this.onAutocompletingInputContextMenu}
+            disabled={this.props.isCommitting}
           />
         </div>
 
@@ -486,6 +513,8 @@ export class CommitMessage extends React.Component<
             autocompletionProviders={this.props.autocompletionProviders}
             ref={this.onDescriptionFieldRef}
             onElementRef={this.onDescriptionTextAreaRef}
+            onContextMenu={this.onAutocompletingInputContextMenu}
+            disabled={this.props.isCommitting}
           />
           {this.renderActionBar()}
         </FocusContainer>

app/src/ui/changes/sidebar.tsx

@@ -48,12 +48,20 @@ interface IChangesSidebarProps {
   readonly gitHubUserStore: GitHubUserStore
   readonly askForConfirmationOnDiscardChanges: boolean
   readonly accounts: ReadonlyArray<Account>
+  /** The name of the currently selected external editor */
+  readonly externalEditorLabel?: string
+
+  /**
+   * Called to open a file using the user's configured applications
+   * @param path The path of the file relative to the root of the repository
+   */
+  readonly onOpenInExternalEditor: (path: string) => void
 }
 
 export class ChangesSidebar extends React.Component<IChangesSidebarProps, {}> {
   private autocompletionProviders: ReadonlyArray<
     IAutocompletionProvider<any>
-  > | null
+  > | null = null
 
   public constructor(props: IChangesSidebarProps) {
     super(props)
@@ -305,6 +313,8 @@ export class ChangesSidebar extends React.Component<IChangesSidebarProps, {}> {
           isCommitting={this.props.isCommitting}
           showCoAuthoredBy={this.props.changes.showCoAuthoredBy}
           coAuthors={this.props.changes.coAuthors}
+          externalEditorLabel={this.props.externalEditorLabel}
+          onOpenInExternalEditor={this.props.onOpenInExternalEditor}
         />
         {this.renderMostRecentLocalCommit()}
       </div>

app/src/ui/clone-repository/clone-github-repository.tsx

@@ -27,9 +27,6 @@ interface ICloneGithubRepositoryProps {
   /** Called when the destination path changes. */
   readonly onPathChanged: (path: string) => void
 
-  /** Called when the dialog should be dismissed. */
-  readonly onDismissed: () => void
-
   /**
    * Called when the user should be prompted to choose a destination directory.
    */
@@ -164,7 +161,6 @@ export class CloneGithubRepository extends React.Component<
         renderItem={this.renderItem}
         renderGroupHeader={this.renderGroupHeader}
         onItemClick={this.onItemClicked}
-        onFilterKeyDown={this.onFilterKeyDown}
         invalidationProps={this.state.repositories}
         groups={this.state.repositories}
         filterText={this.state.filterText}
@@ -177,15 +173,6 @@ export class CloneGithubRepository extends React.Component<
     this.setState({ filterText })
   }
 
-  private onFilterKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      if (this.state.filterText.length === 0) {
-        this.props.onDismissed()
-        event.preventDefault()
-      }
-    }
-  }
-
   private onItemClicked = (item: IClonableRepositoryListItem) => {
     this.setState({ selectedItem: item })
     this.props.onGitHubRepositorySelected(item.url)

app/src/ui/clone-repository/clone-repository.tsx

@@ -185,7 +185,6 @@ export class CloneRepository extends React.Component<
               onPathChanged={this.updateAndValidatePath}
               onGitHubRepositorySelected={this.updateUrl}
               onChooseDirectory={this.onChooseDirectory}
-              onDismissed={this.props.onDismissed}
               shouldClearFilter={this.state.shouldClearFilter}
             />
           )
@@ -358,7 +357,7 @@ export class CloneRepository extends React.Component<
     }
 
     try {
-      this.cloneImpl(url, path)
+      this.cloneImpl(url.trim(), path)
     } catch (e) {
       log.error(`CloneRepostiory: clone failed to complete to ${path}`, e)
       this.setState({ loading: false, error: e })

app/src/ui/create-branch/create-branch-dialog.tsx

@@ -253,7 +253,7 @@ export class CreateBranch extends React.Component<
               label="Name"
               value={this.state.proposedName}
               autoFocus={true}
-              onChange={this.onBranchNameChange}
+              onValueChanged={this.onBranchNameChange}
             />
           </Row>
 
@@ -277,9 +277,8 @@ export class CreateBranch extends React.Component<
     )
   }
 
-  private onBranchNameChange = (event: React.FormEvent<HTMLInputElement>) => {
-    const str = event.currentTarget.value
-    this.updateBranchName(str)
+  private onBranchNameChange = (name: string) => {
+    this.updateBranchName(name)
   }
 
   private updateBranchName(name: string) {

app/src/ui/diff/code-mirror-host.tsx

@@ -52,8 +52,8 @@ interface ICodeMirrorHostProps {
  * A component hosting a CodeMirror instance
  */
 export class CodeMirrorHost extends React.Component<ICodeMirrorHostProps, {}> {
-  private wrapper: HTMLDivElement | null
-  private codeMirror: CodeMirror.Editor | null
+  private wrapper: HTMLDivElement | null = null
+  private codeMirror: CodeMirror.Editor | null = null
 
   /**
    * Gets the internal CodeMirror instance or null if CodeMirror hasn't

app/src/ui/diff/image-diffs/modified-image-diff.tsx

@@ -57,7 +57,7 @@ export class ModifiedImageDiff extends React.Component<
   IModifiedImageDiffProps,
   IModifiedImageDiffState
 > {
-  private container: HTMLElement | null
+  private container: HTMLElement | null = null
 
   private readonly resizeObserver: ResizeObserver
   private resizedTimeoutID: number | null = null

app/src/ui/diff/index.tsx

@@ -30,6 +30,7 @@ import {
   ITextDiff,
   DiffLine,
   DiffLineType,
+  ILargeTextDiff,
 } from '../../models/diff'
 import { Dispatcher } from '../../lib/dispatcher/dispatcher'
 
@@ -56,6 +57,7 @@ import { readPartialFile } from '../../lib/file-system'
 import { DiffSyntaxMode, IDiffSyntaxModeSpec } from './diff-syntax-mode'
 import { highlight } from '../../lib/highlighter/worker'
 import { ITokens } from '../../lib/highlighter/types'
+import { Button } from '../lib/button'
 
 /** The longest line for which we'd try to calculate a line diff. */
 const MaxIntraLineDiffStringLength = 4096
@@ -70,6 +72,10 @@ const narrowNoNewlineSymbol = new OcticonSymbol(
   8,
   'm 16,1 0,3 c 0,0.55 -0.45,1 -1,1 l -3,0 0,2 -3,-3 3,-3 0,2 2,0 0,-2 2,0 z M 8,4 C 8,6.2 6.2,8 4,8 1.8,8 0,6.2 0,4 0,1.8 1.8,0 4,0 6.2,0 8,1.8 8,4 Z M 1.5,5.66 5.66,1.5 C 5.18,1.19 4.61,1 4,1 2.34,1 1,2.34 1,4 1,4.61 1.19,5.17 1.5,5.66 Z M 7,4 C 7,3.39 6.81,2.83 6.5,2.34 L 2.34,6.5 C 2.82,6.81 3.39,7 4,7 5.66,7 7,5.66 7,4 Z'
 )
+
+// image used when no diff is displayed
+const NoDiffImage = encodePathAsUrl(__dirname, 'static/ufo-alert.svg')
+
 type ChangedFile = WorkingDirectoryFileChange | CommittedFileChange
 
 interface ILineFilters {
@@ -300,10 +306,14 @@ interface IDiffProps {
   readonly imageDiffType: ImageDiffType
 }
 
+interface IDiffState {
+  readonly forceShowLargeDiff: boolean
+}
+
 /** A component which renders a diff for a file. */
-export class Diff extends React.Component<IDiffProps, {}> {
-  private codeMirror: Editor | null
-  private gutterWidth: number | null
+export class Diff extends React.Component<IDiffProps, IDiffState> {
+  private codeMirror: Editor | null = null
+  private gutterWidth: number | null = null
 
   /**
    * We store the scroll position before reloading the same diff so that we can
@@ -329,6 +339,14 @@ export class Diff extends React.Component<IDiffProps, {}> {
    */
   private cachedGutterElements = new Map<number, DiffLineGutter>()
 
+  public constructor(props: IDiffProps) {
+    super(props)
+
+    this.state = {
+      forceShowLargeDiff: false,
+    }
+  }
+
   public componentWillReceiveProps(nextProps: IDiffProps) {
     // If we're reloading the same file, we want to save the current scroll
     // position and restore it after the diff's been updated.
@@ -426,6 +444,10 @@ export class Diff extends React.Component<IDiffProps, {}> {
     }
   }
 
+  public render() {
+    return this.renderDiff(this.props.diff)
+  }
+
   public async initDiffSyntaxMode() {
     const cm = this.codeMirror
     const file = this.props.file
@@ -952,6 +974,64 @@ export class Diff extends React.Component<IDiffProps, {}> {
     return null
   }
 
+  private renderLargeTextDiff() {
+    return (
+      <div className="panel empty large-diff">
+        <img src={NoDiffImage} />
+        <p>
+          The diff is too large to be displayed by default.
+          <br />
+          You can try to show it anyways, but performance may be negatively
+          impacted.
+        </p>
+        <Button onClick={this.showLargeDiff}>
+          {__DARWIN__ ? 'Show Diff' : 'Show diff'}
+        </Button>
+      </div>
+    )
+  }
+
+  private renderUnrenderableDiff() {
+    return (
+      <div className="panel empty large-diff">
+        <img src={NoDiffImage} />
+        <p>The diff is too large to be displayed.</p>
+      </div>
+    )
+  }
+
+  private renderLargeText(diff: ILargeTextDiff) {
+    // guaranteed to be set since this function won't be called if text or hunks are null
+    const textDiff: ITextDiff = {
+      text: diff.text!,
+      hunks: diff.hunks!,
+      kind: DiffType.Text,
+      lineEndingsChange: diff.lineEndingsChange,
+    }
+
+    return this.renderTextDiff(textDiff)
+  }
+
+  private renderText(diff: ITextDiff) {
+    if (diff.hunks.length === 0) {
+      if (this.props.file.status === AppFileStatus.New) {
+        return <div className="panel empty">The file is empty</div>
+      }
+
+      if (this.props.file.status === AppFileStatus.Renamed) {
+        return (
+          <div className="panel renamed">
+            The file was renamed but not changed
+          </div>
+        )
+      }
+
+      return <div className="panel empty">No content changes found</div>
+    }
+
+    return this.renderTextDiff(diff)
+  }
+
   private renderBinaryFile() {
     return (
       <BinaryFile
@@ -1044,52 +1124,27 @@ export class Diff extends React.Component<IDiffProps, {}> {
     this.codeMirror = cmh === null ? null : cmh.getEditor()
   }
 
-  public render() {
-    const diff = this.props.diff
-
-    if (diff.kind === DiffType.Image) {
-      return this.renderImage(diff)
-    }
-
-    if (diff.kind === DiffType.Binary) {
-      return this.renderBinaryFile()
-    }
-
-    if (diff.kind === DiffType.TooLarge) {
-      const BlankSlateImage = encodePathAsUrl(
-        __dirname,
-        'static/empty-no-file-selected.svg'
-      )
-      const diffSizeMB = Math.round(diff.length / (1024 * 1024))
-      return (
-        <div className="panel empty">
-          <img src={BlankSlateImage} className="blankslate-image" />
-          The diff returned by Git is {diffSizeMB}MB ({diff.length} bytes),
-          which is larger than what can be displayed in GitHub Desktop.
-        </div>
-      )
-    }
-
-    if (diff.kind === DiffType.Text) {
-      if (diff.hunks.length === 0) {
-        if (this.props.file.status === AppFileStatus.New) {
-          return <div className="panel empty">The file is empty</div>
-        }
-
-        if (this.props.file.status === AppFileStatus.Renamed) {
-          return (
-            <div className="panel renamed">
-              The file was renamed but not changed
-            </div>
-          )
-        }
-
-        return <div className="panel empty">No content changes found</div>
+  private renderDiff(diff: IDiff): JSX.Element | null {
+    switch (diff.kind) {
+      case DiffType.Text:
+        return this.renderText(diff)
+      case DiffType.Binary:
+        return this.renderBinaryFile()
+      case DiffType.Image:
+        return this.renderImage(diff)
+      case DiffType.LargeText: {
+        return this.state.forceShowLargeDiff
+          ? this.renderLargeText(diff)
+          : this.renderLargeTextDiff()
       }
-
-      return this.renderTextDiff(diff)
+      case DiffType.Unrenderable:
+        return this.renderUnrenderableDiff()
+      default:
+        return assertNever(diff, `Unsupported diff type: ${diff}`)
     }
+  }
 
-    return null
+  private showLargeDiff = () => {
+    this.setState({ forceShowLargeDiff: true })
   }
 }

app/src/ui/history/commit-list-item.tsx

@@ -6,10 +6,11 @@ import { RichText } from '../lib/rich-text'
 import { RelativeTime } from '../relative-time'
 import { getDotComAPIEndpoint } from '../../lib/api'
 import { clipboard } from 'electron'
-import { showContextualMenu, IMenuItem } from '../main-process-proxy'
+import { showContextualMenu } from '../main-process-proxy'
 import { CommitAttribution } from '../lib/commit-attribution'
 import { IGitHubUser } from '../../lib/databases/github-user-database'
 import { AvatarStack } from '../lib/avatar-stack'
+import { IMenuItem } from '../../lib/menu-item'
 
 interface ICommitProps {
   readonly gitHubRepository: GitHubRepository | null

app/src/ui/history/commit-list.tsx

@@ -1,5 +1,5 @@
 import * as React from 'react'
-import { Repository } from '../../models/repository'
+import { GitHubRepository } from '../../models/github-repository'
 import { Commit } from '../../models/commit'
 import { CommitListItem } from './commit-list-item'
 import { List } from '../lib/list'
@@ -8,26 +8,52 @@ import { IGitHubUser } from '../../lib/databases'
 const RowHeight = 50
 
 interface ICommitListProps {
-  readonly onCommitChanged: (commit: Commit) => void
-  readonly onScroll: (start: number, end: number) => void
-  readonly onRevertCommit: (commit: Commit) => void
-  readonly onViewCommitOnGitHub: (sha: string) => void
-  readonly repository: Repository
-  readonly history: ReadonlyArray<string>
-  readonly commits: Map<string, Commit>
+  /** The GitHub repository associated with this commit (if found) */
+  readonly gitHubRepository: GitHubRepository | null
+
+  /** The list of commits SHAs to display, in order. */
+  readonly commits: ReadonlyArray<string>
+
+  /** The commits loaded, keyed by their full SHA. */
+  readonly commitLookup: Map<string, Commit>
+
+  /** The SHA of the selected commit */
   readonly selectedSHA: string | null
+
+  /** The lookup for GitHub users related to this repository */
   readonly gitHubUsers: Map<string, IGitHubUser>
+
+  /** The emoji lookup to render images inline */
   readonly emoji: Map<string, string>
+
+  /** The list of known local commits for the current branch */
   readonly localCommitSHAs: ReadonlyArray<string>
+
+  /** Callback which fires when a commit has been selected in the list */
+  readonly onCommitSelected: (commit: Commit) => void
+
+  /** Callback that fires when a scroll event has occurred */
+  readonly onScroll: (start: number, end: number) => void
+
+  /** Callback to fire to revert a given commit in the current repository */
+  readonly onRevertCommit: (commit: Commit) => void
+
+  /** Callback to fire to open a given commit on GitHub */
+  readonly onViewCommitOnGitHub: (sha: string) => void
 }
 
 /** A component which displays the list of commits. */
 export class CommitList extends React.Component<ICommitListProps, {}> {
   private renderCommit = (row: number) => {
-    const sha = this.props.history[row]
-    const commit = this.props.commits.get(sha)
+    const sha = this.props.commits[row]
+    const commit = this.props.commitLookup.get(sha)
 
-    if (!commit) {
+    if (commit == null) {
+      if (__DEV__) {
+        log.warn(
+          `[CommitList]: the commit '${sha}' does not exist in the cache`
+        )
+      }
       return null
     }
 
@@ -36,7 +62,7 @@ export class CommitList extends React.Component<ICommitListProps, {}> {
     return (
       <CommitListItem
         key={commit.sha}
-        gitHubRepository={this.props.repository.gitHubRepository}
+        gitHubRepository={this.props.gitHubRepository}
         isLocal={isLocal}
         commit={commit}
         gitHubUsers={this.props.gitHubUsers}
@@ -48,10 +74,10 @@ export class CommitList extends React.Component<ICommitListProps, {}> {
   }
 
   private onRowChanged = (row: number) => {
-    const sha = this.props.history[row]
-    const commit = this.props.commits.get(sha)
+    const sha = this.props.commits[row]
+    const commit = this.props.commitLookup.get(sha)
     if (commit) {
-      this.props.onCommitChanged(commit)
+      this.props.onCommitSelected(commit)
     }
   }
 
@@ -68,25 +94,25 @@ export class CommitList extends React.Component<ICommitListProps, {}> {
       return -1
     }
 
-    return this.props.history.findIndex(s => s === sha)
+    return this.props.commits.findIndex(s => s === sha)
   }
 
   public render() {
-    if (this.props.history.length === 0) {
+    if (this.props.commits.length === 0) {
       return <div className="panel blankslate">No history</div>
     }
 
     return (
       <div id="commit-list">
         <List
-          rowCount={this.props.history.length}
+          rowCount={this.props.commits.length}
           rowHeight={RowHeight}
           selectedRow={this.rowForSHA(this.props.selectedSHA)}
           rowRenderer={this.renderCommit}
           onSelectionChanged={this.onRowChanged}
           onScroll={this.onScroll}
           invalidationProps={{
-            history: this.props.history,
+            commits: this.props.commits,
             gitHubUsers: this.props.gitHubUsers,
           }}
         />

app/src/ui/history/commit-summary.tsx

@@ -117,7 +117,7 @@ export class CommitSummary extends React.Component<
   ICommitSummaryProps,
   ICommitSummaryState
 > {
-  private descriptionScrollViewRef: HTMLDivElement | null
+  private descriptionScrollViewRef: HTMLDivElement | null = null
   private readonly resizeObserver: ResizeObserver | null = null
   private updateOverflowTimeoutId: number | null = null
 

app/src/ui/history/sidebar.tsx

@@ -16,7 +16,7 @@ interface IHistorySidebarProps {
   readonly history: IHistoryState
   readonly gitHubUsers: Map<string, IGitHubUser>
   readonly emoji: Map<string, string>
-  readonly commits: Map<string, Commit>
+  readonly commitLookup: Map<string, Commit>
   readonly localCommitSHAs: ReadonlyArray<string>
   readonly onRevertCommit: (commit: Commit) => void
   readonly onViewCommitOnGitHub: (sha: string) => void
@@ -26,7 +26,7 @@ interface IHistorySidebarProps {
 export class HistorySidebar extends React.Component<IHistorySidebarProps, {}> {
   private readonly loadChangedFilesScheduler = new ThrottledScheduler(200)
 
-  private onCommitChanged = (commit: Commit) => {
+  private onCommitSelected = (commit: Commit) => {
     this.props.dispatcher.changeHistoryCommitSelection(
       this.props.repository,
       commit.sha
@@ -53,11 +53,11 @@ export class HistorySidebar extends React.Component<IHistorySidebarProps, {}> {
   public render() {
     return (
       <CommitList
-        repository={this.props.repository}
-        commits={this.props.commits}
-        history={this.props.history.history}
+        gitHubRepository={this.props.repository.gitHubRepository}
+        commitLookup={this.props.commitLookup}
+        commits={this.props.history.history}
         selectedSHA={this.props.history.selection.sha}
-        onCommitChanged={this.onCommitChanged}
+        onCommitSelected={this.onCommitSelected}
         onScroll={this.onScroll}
         gitHubUsers={this.props.gitHubUsers}
         emoji={this.props.emoji}

app/src/ui/index.tsx

@@ -149,13 +149,15 @@ document.body.classList.add(`platform-${process.platform}`)
 dispatcher.setAppFocusState(remote.getCurrentWindow().isFocused())
 
 ipcRenderer.on('focus', () => {
-  const state = appStore.getState().selectedState
-  if (!state || state.type !== SelectionType.Repository) {
-    return
+  const { selectedState } = appStore.getState()
+
+  // Refresh the currently selected repository on focus (if
+  // we have a selected repository).
+  if (selectedState && selectedState.type === SelectionType.Repository) {
+    dispatcher.refreshRepository(selectedState.repository)
   }
 
   dispatcher.setAppFocusState(true)
-  dispatcher.refreshRepository(state.repository)
 })
 
 ipcRenderer.on('blur', () => {

app/src/ui/install-globals.ts

@@ -3,10 +3,4 @@ export function installDevGlobals() {
   const g: any = global
   // Expose GitPerf as a global so it can be started.
   g.GitPerf = require('./lib/git-perf')
-
-  // Expose Perf on the window so that the React Perf dev tool extension can
-  // find it.
-  const w: any = window
-  const Perf = require('react-addons-perf')
-  w.Perf = Perf
 }

app/src/ui/lib/authentication-form.tsx

@@ -83,14 +83,14 @@ export class AuthenticationForm extends React.Component<
           label="Username or email address"
           disabled={disabled}
           autoFocus={true}
-          onChange={this.onUsernameChange}
+          onValueChanged={this.onUsernameChange}
         />
 
         <TextBox
           label="Password"
           type="password"
           disabled={disabled}
-          onChange={this.onPasswordChange}
+          onValueChanged={this.onPasswordChange}
         />
 
         {this.renderError()}
@@ -121,7 +121,7 @@ export class AuthenticationForm extends React.Component<
             className="forgot-password-link"
             uri={this.props.forgotPasswordUrl}
           >
-            Forgot password
+            Forgot password?
           </LinkButton>
         ) : null}
       </div>
@@ -173,12 +173,12 @@ export class AuthenticationForm extends React.Component<
     return <Errors>{error.message}</Errors>
   }
 
-  private onUsernameChange = (event: React.FormEvent<HTMLInputElement>) => {
-    this.setState({ username: event.currentTarget.value })
+  private onUsernameChange = (username: string) => {
+    this.setState({ username })
   }
 
-  private onPasswordChange = (event: React.FormEvent<HTMLInputElement>) => {
-    this.setState({ password: event.currentTarget.value })
+  private onPasswordChange = (password: string) => {
+    this.setState({ password })
   }
 
   private signInWithBrowser = (event?: React.MouseEvent<HTMLButtonElement>) => {

app/src/ui/lib/author-input.tsx

@@ -9,6 +9,8 @@ import { compare } from '../../lib/compare'
 import { arrayEquals } from '../../lib/equality'
 import { OcticonSymbol } from '../octicons'
 import { IAuthor } from '../../models/author'
+import { showContextualMenu } from '../main-process-proxy'
+import { IMenuItem } from '../../lib/menu-item'
 
 interface IAuthorInputProps {
   /**
@@ -36,6 +38,12 @@ interface IAuthorInputProps {
    * input field.
    */
   readonly onAuthorsUpdated: (authors: ReadonlyArray<IAuthor>) => void
+
+  /**
+   * Whether or not the input should be read-only and styled as being
+   * disabled. When disabled the component will not accept focus.
+   */
+  readonly disabled: boolean
 }
 
 /**
@@ -488,6 +496,12 @@ export class AuthorInput extends React.Component<IAuthorInputProps, {}> {
   }
 
   public componentWillReceiveProps(nextProps: IAuthorInputProps) {
+    const cm = this.editor
+
+    if (!cm) {
+      return
+    }
+
     // If the authors prop have changed from our internal representation
     // we'll throw up our hands and reset the input to whatever we're
     // given.
@@ -495,12 +509,13 @@ export class AuthorInput extends React.Component<IAuthorInputProps, {}> {
       nextProps.authors !== this.props.authors &&
       !arrayEquals(this.authors, nextProps.authors)
     ) {
-      const cm = this.editor
-      if (cm) {
-        cm.operation(() => {
-          this.reset(cm, nextProps.authors)
-        })
-      }
+      cm.operation(() => {
+        this.reset(cm, nextProps.authors)
+      })
+    }
+
+    if (nextProps.disabled !== this.props.disabled) {
+      cm.setOption('readOnly', nextProps.disabled ? 'nocursor' : false)
     }
   }
 
@@ -702,6 +717,7 @@ export class AuthorInput extends React.Component<IAuthorInputProps, {}> {
         'Ctrl-Enter': false,
         'Cmd-Enter': false,
       },
+      readOnly: this.props.disabled ? 'nocursor' : false,
       hintOptions: {
         completeOnSingleClick: true,
         completeSingle: false,
@@ -743,18 +759,50 @@ export class AuthorInput extends React.Component<IAuthorInputProps, {}> {
       this.updateAuthors(cm)
     })
 
+    const wrapperElem = cm.getWrapperElement()
+
     // Do the very least we can do to pretend that we're a
     // single line textbox. Users can still paste newlines
     // though and if the do we don't care.
-    cm.getWrapperElement().addEventListener('keypress', (e: KeyboardEvent) => {
+    wrapperElem.addEventListener('keypress', (e: KeyboardEvent) => {
       if (!e.defaultPrevented && e.key === 'Enter') {
         e.preventDefault()
       }
     })
 
+    wrapperElem.addEventListener('contextmenu', e => {
+      this.onContextMenu(cm, e)
+    })
+
     return cm
   }
 
+  private onContextMenu(cm: Editor, e: PointerEvent) {
+    e.preventDefault()
+
+    const menu: IMenuItem[] = [
+      { label: 'Undo', action: () => cm.getDoc().undo() },
+      { label: 'Redo', action: () => cm.getDoc().redo() },
+      { type: 'separator' },
+      { role: 'cut' },
+      { role: 'copy' },
+      { role: 'paste' },
+    ]
+
+    if (__WIN32__) {
+      menu.push({ type: 'separator' })
+    }
+
+    menu.push({
+      label: __DARWIN__ ? 'Select All' : 'Select all',
+      action: () => {
+        cm.execCommand('selectAll')
+      },
+    })
+
+    showContextualMenu(menu)
+  }
+
   private updateAuthors(cm: Editor) {
     const markers = this.getAllHandleMarks(cm).sort(orderByPosition)
     const authors = new Array<IAuthor>()
@@ -811,7 +859,13 @@ export class AuthorInput extends React.Component<IAuthorInputProps, {}> {
   }
 
   public render() {
-    const className = classNames('author-input-component', this.props.className)
+    const className = classNames(
+      'author-input-component',
+      this.props.className,
+      {
+        disabled: this.props.disabled,
+      }
+    )
     return <div className={className} ref={this.onContainerRef} />
   }
 }

app/src/ui/lib/button.tsx

@@ -116,18 +116,6 @@ export class Button extends React.Component<IButtonProps, {}> {
       this.props.className
     )
 
-    let ariaExpanded: string | undefined = undefined
-
-    if (this.props.ariaExpanded !== undefined) {
-      ariaExpanded = this.props.ariaExpanded ? 'true' : 'false'
-    }
-
-    let ariaHasPopup: string | undefined = undefined
-
-    if (this.props.ariaHasPopup !== undefined) {
-      ariaHasPopup = this.props.ariaHasPopup ? 'true' : 'false'
-    }
-
     return (
       <button
         className={className}
@@ -138,8 +126,8 @@ export class Button extends React.Component<IButtonProps, {}> {
         tabIndex={this.props.tabIndex}
         onMouseEnter={this.props.onMouseEnter}
         role={this.props.role}
-        aria-expanded={ariaExpanded}
-        aria-haspopup={ariaHasPopup}
+        aria-expanded={this.props.ariaExpanded}
+        aria-haspopup={this.props.ariaHasPopup}
       >
         {this.props.children}
       </button>

app/src/ui/lib/checkbox.tsx

@@ -36,7 +36,7 @@ interface ICheckboxState {
 
 /** A checkbox component which supports the mixed value. */
 export class Checkbox extends React.Component<ICheckboxProps, ICheckboxState> {
-  private input: HTMLInputElement | null
+  private input: HTMLInputElement | null = null
 
   private onChange = (event: React.FormEvent<HTMLInputElement>) => {
     if (this.props.onChange) {

app/src/ui/lib/configure-git-user.tsx

@@ -98,16 +98,16 @@ export class ConfigureGitUser extends React.Component<
         <Form className="sign-in-form" onSubmit={this.save}>
           <TextBox
             label="Name"
-            placeholder="Hubot"
+            placeholder="Your Name"
             value={this.state.name}
-            onChange={this.onNameChange}
+            onValueChanged={this.onNameChange}
           />
 
           <TextBox
             label="Email"
-            placeholder="hubot@github.com"
+            placeholder="your-email@example.com"
             value={this.state.email}
-            onChange={this.onEmailChange}
+            onValueChanged={this.onEmailChange}
           />
 
           <Row>
@@ -131,16 +131,13 @@ export class ConfigureGitUser extends React.Component<
     )
   }
 
-  private onNameChange = (event: React.FormEvent<HTMLInputElement>) => {
+  private onNameChange = (name: string) => {
     this.setState({
-      name: event.currentTarget.value,
-      email: this.state.email,
-      avatarURL: this.state.avatarURL,
+      name,
     })
   }
 
-  private onEmailChange = (event: React.FormEvent<HTMLInputElement>) => {
-    const email = event.currentTarget.value
+  private onEmailChange = (email: string) => {
     const avatarURL = this.avatarURLForEmail(email)
 
     this.setState({

app/src/ui/lib/filter-list.tsx

@@ -121,7 +121,6 @@ interface IFilterListProps<T extends IFilterListItem> {
 
 interface IFilterListState<T extends IFilterListItem> {
   readonly rows: ReadonlyArray<IFilterListRow<T>>
-
   readonly selectedRow: number
 }
 
@@ -144,7 +143,7 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
   IFilterListState<T>
 > {
   private list: List | null = null
-  private filterInput: HTMLInputElement | null = null
+  private filterTextBox: TextBox | null = null
 
   public constructor(props: IFilterListProps<T>) {
     super(props)
@@ -152,105 +151,10 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
     this.state = createStateUpdate(props)
   }
 
-  public render() {
-    return (
-      <div className={classnames('filter-list', this.props.className)}>
-        {this.props.renderPreList ? this.props.renderPreList() : null}
-
-        <Row className="filter-field-row">
-          <TextBox
-            type="search"
-            autoFocus={true}
-            placeholder="Filter"
-            className="filter-list-filter-field"
-            onChange={this.onFilterChanged}
-            onKeyDown={this.onKeyDown}
-            onInputRef={this.onInputRef}
-            value={this.props.filterText}
-            disabled={this.props.disabled}
-          />
-
-          {this.props.renderPostFilter ? this.props.renderPostFilter() : null}
-        </Row>
-
-        <div className="filter-list-container">{this.renderContent()}</div>
-      </div>
-    )
-  }
-
-  private renderContent() {
-    if (this.state.rows.length === 0 && this.props.renderNoItems) {
-      return this.props.renderNoItems()
-    } else {
-      return (
-        <List
-          rowCount={this.state.rows.length}
-          rowRenderer={this.renderRow}
-          rowHeight={this.props.rowHeight}
-          selectedRow={this.state.selectedRow}
-          onSelectionChanged={this.onSelectionChanged}
-          onRowClick={this.onRowClick}
-          onRowKeyDown={this.onRowKeyDown}
-          canSelectRow={this.canSelectRow}
-          ref={this.onListRef}
-          invalidationProps={{
-            ...this.props,
-            ...this.props.invalidationProps,
-          }}
-        />
-      )
-    }
-  }
-
   public componentWillReceiveProps(nextProps: IFilterListProps<T>) {
     this.setState(createStateUpdate(nextProps))
   }
 
-  private onSelectionChanged = (index: number, source: SelectionSource) => {
-    this.setState({ selectedRow: index })
-
-    if (this.props.onSelectionChanged) {
-      const row = this.state.rows[index]
-      if (row.kind === 'item') {
-        this.props.onSelectionChanged(row.item, source)
-      }
-    }
-  }
-
-  private renderRow = (index: number) => {
-    const row = this.state.rows[index]
-    if (row.kind === 'item') {
-      return this.props.renderItem(row.item, row.matches)
-    } else if (this.props.renderGroupHeader) {
-      return this.props.renderGroupHeader(row.identifier)
-    } else {
-      return null
-    }
-  }
-
-  private onListRef = (instance: List | null) => {
-    this.list = instance
-  }
-
-  private onInputRef = (instance: HTMLInputElement | null) => {
-    this.filterInput = instance
-
-    if (
-      this.filterInput &&
-      this.props.filterText &&
-      this.props.filterText.length > 0
-    ) {
-      this.filterInput.select()
-    }
-  }
-
-  private onFilterChanged = (event: React.FormEvent<HTMLInputElement>) => {
-    const text = event.currentTarget.value
-    if (this.props.onFilterTextChanged) {
-      this.props.onFilterTextChanged(text)
-    }
-  }
-
   public componentDidUpdate(
     prevProps: IFilterListProps<T>,
     prevState: IFilterListState<T>
@@ -284,6 +188,98 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
     }
   }
 
+  public componentDidMount() {
+    if (this.filterTextBox != null) {
+      this.filterTextBox.selectAll()
+    }
+  }
+
+  public render() {
+    return (
+      <div className={classnames('filter-list', this.props.className)}>
+        {this.props.renderPreList ? this.props.renderPreList() : null}
+
+        <Row className="filter-field-row">
+          <TextBox
+            ref={this.onTextBoxRef}
+            type="search"
+            autoFocus={true}
+            placeholder="Filter"
+            className="filter-list-filter-field"
+            onValueChanged={this.onFilterValueChanged}
+            onKeyDown={this.onKeyDown}
+            value={this.props.filterText}
+            disabled={this.props.disabled}
+          />
+
+          {this.props.renderPostFilter ? this.props.renderPostFilter() : null}
+        </Row>
+
+        <div className="filter-list-container">{this.renderContent()}</div>
+      </div>
+    )
+  }
+
+  private renderContent() {
+    if (this.state.rows.length === 0 && this.props.renderNoItems) {
+      return this.props.renderNoItems()
+    } else {
+      return (
+        <List
+          ref={this.onListRef}
+          rowCount={this.state.rows.length}
+          rowRenderer={this.renderRow}
+          rowHeight={this.props.rowHeight}
+          selectedRow={this.state.selectedRow}
+          onSelectionChanged={this.onSelectionChanged}
+          onRowClick={this.onRowClick}
+          onRowKeyDown={this.onRowKeyDown}
+          canSelectRow={this.canSelectRow}
+          invalidationProps={{
+            ...this.props,
+            ...this.props.invalidationProps,
+          }}
+        />
+      )
+    }
+  }
+
+  private renderRow = (index: number) => {
+    const row = this.state.rows[index]
+    if (row.kind === 'item') {
+      return this.props.renderItem(row.item, row.matches)
+    } else if (this.props.renderGroupHeader) {
+      return this.props.renderGroupHeader(row.identifier)
+    } else {
+      return null
+    }
+  }
+
+  private onTextBoxRef = (component: TextBox | null) => {
+    this.filterTextBox = component
+  }
+
+  private onListRef = (instance: List | null) => {
+    this.list = instance
+  }
+
+  private onFilterValueChanged = (text: string) => {
+    if (this.props.onFilterTextChanged) {
+      this.props.onFilterTextChanged(text)
+    }
+  }
+
+  private onSelectionChanged = (index: number, source: SelectionSource) => {
+    this.setState({ selectedRow: index })
+
+    if (this.props.onSelectionChanged) {
+      const row = this.state.rows[index]
+      if (row.kind === 'item') {
+        this.props.onSelectionChanged(row.item, source)
+      }
+    }
+  }
+
   private canSelectRow = (index: number) => {
     if (this.props.disabled) {
       return false
@@ -309,26 +305,30 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
       return
     }
 
-    let focusInput = false
     const firstSelectableRow = list.nextSelectableRow('down', -1)
     const lastSelectableRow = list.nextSelectableRow('up', 0)
+    let shouldFocus = false
+
     if (event.key === 'ArrowUp' && row === firstSelectableRow) {
-      focusInput = true
+      shouldFocus = true
     } else if (event.key === 'ArrowDown' && row === lastSelectableRow) {
-      focusInput = true
+      shouldFocus = true
     }
 
-    if (focusInput) {
-      const input = this.filterInput
-      if (input) {
+    if (shouldFocus) {
+      const textBox = this.filterTextBox
+
+      if (textBox) {
         event.preventDefault()
-        input.focus()
+        textBox.focus()
       }
     }
   }
 
   private onKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
     const list = this.list
+    const key = event.key
+
     if (!list) {
       return
     }
@@ -341,7 +341,7 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
       return
     }
 
-    if (event.key === 'ArrowDown') {
+    if (key === 'ArrowDown') {
       if (this.state.rows.length > 0) {
         const selectedRow = list.nextSelectableRow('down', -1)
         if (selectedRow != null) {
@@ -352,7 +352,7 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
       }
 
       event.preventDefault()
-    } else if (event.key === 'ArrowUp') {
+    } else if (key === 'ArrowUp') {
       if (this.state.rows.length > 0) {
         const selectedRow = list.nextSelectableRow('up', 0)
         if (selectedRow != null) {
@@ -363,7 +363,7 @@ export class FilterList<T extends IFilterListItem> extends React.Component<
       }
 
       event.preventDefault()
-    } else if (event.key === 'Enter') {
+    } else if (key === 'Enter') {
       // no repositories currently displayed, bail out
       if (!this.state.rows.length) {
         return event.preventDefault()

app/src/ui/lib/list/list.tsx

@@ -210,7 +210,7 @@ export class List extends React.Component<IListProps, IListState> {
   private lastScroll: 'grid' | 'fake' | null = null
 
   private list: HTMLDivElement | null = null
-  private grid: React.Component<any, any> | null
+  private grid: React.Component<any, any> | null = null
   private readonly resizeObserver: ResizeObserver | null = null
   private updateSizeTimeoutId: number | null = null
 

app/src/ui/lib/text-area.tsx

@@ -1,5 +1,6 @@
 import * as React from 'react'
 import * as classNames from 'classnames'
+import { showContextualMenu } from '../main-process-proxy'
 
 interface ITextAreaProps {
   /** The label for the textarea field. */
@@ -58,6 +59,10 @@ export class TextArea extends React.Component<ITextAreaProps, {}> {
       this.props.onValueChanged(event.currentTarget.value)
     }
   }
+  private onContextMenu = (event: React.MouseEvent<any>) => {
+    event.preventDefault()
+    showContextualMenu([{ role: 'editMenu' }])
+  }
 
   public render() {
     const className = classNames(
@@ -78,6 +83,7 @@ export class TextArea extends React.Component<ITextAreaProps, {}> {
           onChange={this.onChange}
           onKeyDown={this.props.onKeyDown}
           ref={this.props.onTextAreaRef}
+          onContextMenu={this.onContextMenu}
         />
       </label>
     )

app/src/ui/lib/text-box.tsx

@@ -2,6 +2,7 @@ import * as React from 'react'
 import * as classNames from 'classnames'
 import { createUniqueId, releaseUniqueId } from './id-pool'
 import { LinkButton } from './link-button'
+import { showContextualMenu } from '../main-process-proxy'
 
 interface ITextBoxProps {
   /** The label for the input field. */
@@ -25,9 +26,6 @@ interface ITextBoxProps {
   /** Whether the input field is disabled. */
   readonly disabled?: boolean
 
-  /** Called when the user changes the value in the input field. */
-  readonly onChange?: (event: React.FormEvent<HTMLInputElement>) => void
-
   /**
    * Called when the user changes the value in the input field.
    *
@@ -46,9 +44,6 @@ interface ITextBoxProps {
   /** The type of the input. Defaults to `text`. */
   readonly type?: 'text' | 'search' | 'password'
 
-  /** A callback to receive the underlying `input` instance. */
-  readonly onInputRef?: (instance: HTMLInputElement | null) => void
-
   /**
    * An optional text for a link label element. A link label is, for the purposes
    * of this control an anchor element that's rendered alongside (ie on the same)
@@ -97,6 +92,8 @@ interface ITextBoxState {
 
 /** An input element with app-standard styles. */
 export class TextBox extends React.Component<ITextBoxProps, ITextBoxState> {
+  private inputElement: HTMLInputElement | null = null
+
   public componentWillMount() {
     const friendlyName = this.props.label || this.props.placeholder
     const inputId = createUniqueId(`TextBox_${friendlyName}`)
@@ -116,26 +113,40 @@ export class TextBox extends React.Component<ITextBoxProps, ITextBoxState> {
     }
   }
 
+  /**
+   * Selects all text (if any) in the inner text input element. Note that this method does not
+   * automatically move keyboard focus, see the focus method for that
+   */
+  public selectAll() {
+    if (this.inputElement !== null) {
+      this.inputElement.select()
+    }
+  }
+
+  /**
+   * Programmatically moves keyboard focus to the inner text input element if it can be focused
+   * (i.e. if it's not disabled explicitly or implicitly through for example a fieldset).
+   */
+  public focus() {
+    if (this.inputElement === null) {
+      return
+    }
+
+    this.inputElement.focus()
+  }
+
   private onChange = (event: React.FormEvent<HTMLInputElement>) => {
     const value = event.currentTarget.value
 
-    if (this.props.onChange) {
-      this.props.onChange(event)
-    }
-
-    const defaultPrevented = event.defaultPrevented
-
     this.setState({ value }, () => {
-      if (this.props.onValueChanged && !defaultPrevented) {
+      if (this.props.onValueChanged) {
         this.props.onValueChanged(value)
       }
     })
   }
 
-  private onRef = (instance: HTMLInputElement | null) => {
-    if (this.props.onInputRef) {
-      this.props.onInputRef(instance)
-    }
+  private onInputRef = (element: HTMLInputElement | null) => {
+    this.inputElement = element
   }
 
   private renderLabelLink() {
@@ -167,6 +178,32 @@ export class TextBox extends React.Component<ITextBoxProps, ITextBoxState> {
     )
   }
 
+  private onContextMenu = (event: React.MouseEvent<any>) => {
+    event.preventDefault()
+    showContextualMenu([{ role: 'editMenu' }])
+  }
+
+  private onKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
+    if (
+      this.state.value !== '' &&
+      this.props.type === 'search' &&
+      event.key === 'Escape'
+    ) {
+      const value = ''
+
+      event.preventDefault()
+      this.setState({ value })
+
+      if (this.props.onValueChanged) {
+        this.props.onValueChanged(value)
+      }
+    }
+
+    if (this.props.onKeyDown !== undefined) {
+      this.props.onKeyDown(event)
+    }
+  }
+
   public render() {
     const className = classNames('text-box-component', this.props.className)
     const inputId = this.props.label ? this.state.inputId : undefined
@@ -177,15 +214,16 @@ export class TextBox extends React.Component<ITextBoxProps, ITextBoxState> {
 
         <input
           id={inputId}
+          ref={this.onInputRef}
           autoFocus={this.props.autoFocus}
           disabled={this.props.disabled}
           type={this.props.type}
           placeholder={this.props.placeholder}
           value={this.state.value}
           onChange={this.onChange}
-          onKeyDown={this.props.onKeyDown}
-          ref={this.onRef}
+          onKeyDown={this.onKeyDown}
           tabIndex={this.props.tabIndex}
+          onContextMenu={this.onContextMenu}
         />
       </div>
     )

app/src/ui/lib/throttled-scheduler.ts

@@ -1,7 +1,7 @@
 /** A utility class which allows for throttling arbitrary functions */
 export class ThrottledScheduler {
   private delay: number
-  private timeoutId: number
+  private timeoutId: number | null = null
 
   /**
    * Initialize a new instance of the ThrottledScheduler class
@@ -19,12 +19,14 @@ export class ThrottledScheduler {
    * as no other functions are queued.
    */
   public queue(func: Function) {
-    window.clearTimeout(this.timeoutId)
+    this.clear()
     this.timeoutId = window.setTimeout(func, this.delay)
   }
 
   /** Resets the scheduler and unschedules queued callback (if any) */
   public clear() {
-    window.clearTimeout(this.timeoutId)
+    if (this.timeoutId != null) {
+      window.clearTimeout(this.timeoutId)
+    }
   }
 }

app/src/ui/main-process-proxy.ts

@@ -2,6 +2,7 @@ import { ipcRenderer } from 'electron'
 import { ExecutableMenuItem } from '../models/app-menu'
 import { MenuIDs } from '../main-process/menu'
 import { IMenuItemState } from '../lib/menu-update'
+import { IMenuItem } from '../lib/menu-item'
 
 /** Set the menu item's enabledness. */
 export function updateMenuState(
@@ -52,20 +53,6 @@ export function getAppMenu() {
   ipcRenderer.send('get-app-menu')
 }
 
-export interface IMenuItem {
-  /** The user-facing label. */
-  readonly label?: string
-
-  /** The action to invoke when the user selects the item. */
-  readonly action?: () => void
-
-  /** The type of item. */
-  readonly type?: 'separator'
-
-  /** Is the menu item enabled? Defaults to true. */
-  readonly enabled?: boolean
-}
-
 /**
  * There's currently no way for us to know when a contextual menu is closed (see
  * https://github.com/electron/electron/issues/9441). So we'll store the latest

app/src/ui/merge-branch/merge.tsx

@@ -83,15 +83,6 @@ export class Merge extends React.Component<IMergeProps, IMergeState> {
     this.setState({ filterText })
   }
 
-  private onFilterKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      if (this.state.filterText.length === 0) {
-        this.props.onDismissed()
-        event.preventDefault()
-      }
-    }
-  }
-
   private onSelectionChanged = async (selectedBranch: Branch | null) => {
     if (selectedBranch) {
       this.setState({ selectedBranch })
@@ -161,7 +152,6 @@ export class Merge extends React.Component<IMergeProps, IMergeState> {
             defaultBranch={this.props.defaultBranch}
             recentBranches={this.props.recentBranches}
             filterText={this.state.filterText}
-            onFilterKeyDown={this.onFilterKeyDown}
             onFilterTextChanged={this.onFilterTextChanged}
             selectedBranch={selectedBranch}
             onSelectionChanged={this.onSelectionChanged}

app/src/ui/octicons/repository.ts

@@ -10,6 +10,10 @@ export function iconForRepository(repository: Repository | CloningRepository) {
     return OcticonSymbol.desktopDownload
   }
 
+  if (repository.missing) {
+    return OcticonSymbol.alert
+  }
+
   const gitHubRepo = repository.gitHubRepository
   if (!gitHubRepo) {
     return OcticonSymbol.deviceDesktop

app/src/ui/publish-repository/publish-repository.tsx

@@ -78,12 +78,12 @@ export class PublishRepository extends React.Component<
     this.props.onSettingsChanged(newSettings)
   }
 
-  private onNameChange = (event: React.FormEvent<HTMLInputElement>) => {
-    this.updateSettings({ name: event.currentTarget.value })
+  private onNameChange = (name: string) => {
+    this.updateSettings({ name })
   }
 
-  private onDescriptionChange = (event: React.FormEvent<HTMLInputElement>) => {
-    this.updateSettings({ description: event.currentTarget.value })
+  private onDescriptionChange = (description: string) => {
+    this.updateSettings({ description })
   }
 
   private onPrivateChange = (event: React.FormEvent<HTMLInputElement>) => {
@@ -146,7 +146,7 @@ export class PublishRepository extends React.Component<
             label="Name"
             value={this.props.settings.name}
             autoFocus={true}
-            onChange={this.onNameChange}
+            onValueChanged={this.onNameChange}
           />
         </Row>
 
@@ -154,7 +154,7 @@ export class PublishRepository extends React.Component<
           <TextBox
             label="Description"
             value={this.props.settings.description}
-            onChange={this.onDescriptionChange}
+            onValueChanged={this.onDescriptionChange}
           />
         </Row>
 

app/src/ui/relative-time.tsx

@@ -39,7 +39,7 @@ export class RelativeTime extends React.Component<
   IRelativeTimeProps,
   IRelativeTimeState
 > {
-  private timer: number | null
+  private timer: number | null = null
 
   public constructor(props: IRelativeTimeProps) {
     super(props)

app/src/ui/rename-branch/rename-branch-dialog.tsx

@@ -47,8 +47,7 @@ export class RenameBranch extends React.Component<
               label="Name"
               autoFocus={true}
               value={this.state.newName}
-              onChange={this.onNameChange}
-              onKeyDown={this.onKeyDown}
+              onValueChanged={this.onNameChange}
             />
           </Row>
           {renderBranchNameWarning(
@@ -69,14 +68,8 @@ export class RenameBranch extends React.Component<
     )
   }
 
-  private onKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      this.props.dispatcher.closePopup()
-    }
-  }
-
-  private onNameChange = (event: React.FormEvent<HTMLInputElement>) => {
-    this.setState({ newName: event.currentTarget.value })
+  private onNameChange = (name: string) => {
+    this.setState({ newName: name })
   }
 
   private cancel = () => {

app/src/ui/repositories-list/repositories-list.tsx

@@ -40,9 +40,6 @@ interface IRepositoriesListProps {
   /** The current external editor selected by the user */
   readonly externalEditorLabel?: string
 
-  /** Called when the repositories list should be closed. */
-  readonly onClose: () => void
-
   /** The label for the user's preferred shell. */
   readonly shellLabel: string
 
@@ -107,15 +104,6 @@ export class RepositoriesList extends React.Component<
     this.props.onSelectionChanged(item.repository)
   }
 
-  private onFilterKeyDown = (event: React.KeyboardEvent<HTMLInputElement>) => {
-    if (event.key === 'Escape') {
-      if (this.props.filterText.length === 0) {
-        this.props.onClose()
-        event.preventDefault()
-      }
-    }
-  }
-
   public render() {
     if (this.props.repositories.length < 1) {
       return this.noRepositories()
@@ -149,7 +137,6 @@ export class RepositoriesList extends React.Component<
           renderItem={this.renderItem}
           renderGroupHeader={this.renderGroupHeader}
           onItemClick={this.onItemClick}
-          onFilterKeyDown={this.onFilterKeyDown}
           groups={groups}
           invalidationProps={{
             repositories: this.props.repositories,

app/src/ui/repositories-list/repository-list-item.tsx

@@ -1,8 +1,9 @@
 import * as React from 'react'
 import { Repository } from '../../models/repository'
 import { Octicon, iconForRepository } from '../octicons'
-import { showContextualMenu, IMenuItem } from '../main-process-proxy'
+import { showContextualMenu } from '../main-process-proxy'
 import { Repositoryish } from './group-repositories'
+import { IMenuItem } from '../../lib/menu-item'
 import { HighlightText } from '../lib/highlight-text'
 
 const defaultEditorLabel = __DARWIN__

app/src/ui/repository-settings/git-ignore.tsx

@@ -2,6 +2,7 @@ import * as React from 'react'
 import { DialogContent } from '../dialog'
 import { TextArea } from '../lib/text-area'
 import { LinkButton } from '../lib/link-button'
+import { Ref } from '../lib/ref'
 
 interface IGitIgnoreProps {
   readonly text: string | null
@@ -15,14 +16,14 @@ export class GitIgnore extends React.Component<IGitIgnoreProps, {}> {
     return (
       <DialogContent>
         <p>
-          The .gitignore file controls which files are tracked by Git and which
-          are ignored. Check out{' '}
+          Editing <Ref>.gitignore</Ref>. This file specifies intentionally
+          untracked files that Git should ignore. Files already tracked by Git
+          are not affected.{' '}
           <LinkButton onClick={this.props.onShowExamples}>
-            git-scm.com
-          </LinkButton>{' '}
-          for more information about the file format, or simply ignore a file by
-          right clicking on it in the uncommitted changes view.
+            Learn more
+          </LinkButton>
         </p>
+
         <TextArea
           placeholder="Ignored files"
           value={this.props.text || ''}

app/src/ui/repository-settings/repository-settings.tsx

@@ -190,7 +190,7 @@ export class RepositorySettings extends React.Component<
       try {
         await this.props.dispatcher.saveGitIgnore(
           this.props.repository,
-          this.state.ignoreText || ''
+          this.state.ignoreText
         )
       } catch (e) {
         log.error(

app/src/ui/repository.tsx

@@ -35,6 +35,15 @@ interface IRepositoryProps {
   readonly imageDiffType: ImageDiffType
   readonly askForConfirmationOnDiscardChanges: boolean
   readonly accounts: ReadonlyArray<Account>
+
+  /** The name of the currently selected external editor */
+  readonly externalEditorLabel?: string
+
+  /**
+   * Called to open a file using the user's configured applications
+   * @param path The path of the file relative to the root of the repository
+   */
+  readonly onOpenInExternalEditor: (path: string) => void
 }
 
 const enum Tab {
@@ -76,7 +85,7 @@ export class RepositoryView extends React.Component<IRepositoryProps, {}> {
       localCommitSHAs.length > 0 ? localCommitSHAs[0] : null
     const mostRecentLocalCommit =
       (mostRecentLocalCommitSHA
-        ? this.props.state.commits.get(mostRecentLocalCommitSHA)
+        ? this.props.state.commitLookup.get(mostRecentLocalCommitSHA)
         : null) || null
 
     // -1 Because of right hand side border
@@ -101,6 +110,8 @@ export class RepositoryView extends React.Component<IRepositoryProps, {}> {
           this.props.askForConfirmationOnDiscardChanges
         }
         accounts={this.props.accounts}
+        externalEditorLabel={this.props.externalEditorLabel}
+        onOpenInExternalEditor={this.props.onOpenInExternalEditor}
       />
     )
   }
@@ -113,7 +124,7 @@ export class RepositoryView extends React.Component<IRepositoryProps, {}> {
         history={this.props.state.historyState}
         gitHubUsers={this.props.state.gitHubUsers}
         emoji={this.props.emoji}
-        commits={this.props.state.commits}
+        commitLookup={this.props.state.commitLookup}
         localCommitSHAs={this.props.state.localCommitSHAs}
         onRevertCommit={this.onRevertCommit}
         onViewCommitOnGitHub={this.props.onViewCommitOnGitHub}
@@ -190,7 +201,7 @@ export class RepositoryView extends React.Component<IRepositoryProps, {}> {
           dispatcher={this.props.dispatcher}
           history={this.props.state.historyState}
           emoji={this.props.emoji}
-          commits={this.props.state.commits}
+          commits={this.props.state.commitLookup}
           commitSummaryWidth={this.props.commitSummaryWidth}
           gitHubUsers={this.props.state.gitHubUsers}
           imageDiffType={this.props.imageDiffType}

app/src/ui/resizable/resizable.tsx

@@ -13,8 +13,8 @@ export class Resizable extends React.Component<IResizableProps, {}> {
     maximumWidth: 350,
   }
 
-  private startWidth: number | null
-  private startX: number
+  private startWidth: number | null = null
+  private startX: number | null = null
 
   /**
    * Returns the current width as determined by props.
@@ -55,7 +55,7 @@ export class Resizable extends React.Component<IResizableProps, {}> {
    * Handler for when the user moves the mouse while dragging
    */
   private handleDragMove = (e: MouseEvent) => {
-    if (!this.startWidth) {
+    if (this.startWidth == null || this.startX == null) {
       return
     }
 

app/src/ui/sign-in/sign-in.tsx

@@ -203,10 +203,16 @@ export class SignIn extends React.Component<ISignInProps, ISignInState> {
             value={this.state.password}
             type="password"
             onValueChanged={this.onPasswordChanged}
-            labelLinkText="Forgot password?"
-            labelLinkUri={state.forgotPasswordUrl}
           />
         </Row>
+        <Row>
+          <LinkButton
+            className="forgot-password-link-sign-in"
+            uri={state.forgotPasswordUrl}
+          >
+            Forgot password?
+          </LinkButton>
+        </Row>
 
         <div className="horizontal-rule">
           <span className="horizontal-rule-content">or</span>
@@ -239,6 +245,7 @@ export class SignIn extends React.Component<ISignInProps, ISignInState> {
             onValueChanged={this.onOTPTokenChanged}
             labelLinkText={`What's this?`}
             labelLinkUri="https://help.github.com/articles/providing-your-2fa-authentication-code/"
+            autoFocus={true}
           />
         </Row>
       </DialogContent>

app/src/ui/toolbar/branch-dropdown.tsx

@@ -8,7 +8,6 @@ import { IRepositoryState } from '../../lib/app-state'
 import { BranchesContainer, PullRequestBadge } from '../branches'
 import { assertNever } from '../../lib/fatal-error'
 import { BranchesTab } from '../../models/branches-tab'
-import { enablePRIntegration } from '../../lib/feature-flag'
 import { PullRequest } from '../../models/pull-request'
 
 interface IBranchDropdownProps {
@@ -104,7 +103,7 @@ export class BranchDropdown extends React.Component<IBranchDropdownProps> {
     } else if (tip.kind === TipState.Unborn) {
       title = tip.ref
       tooltip = `Current branch is ${tip.ref}`
-      canOpen = false
+      canOpen = branchesState.allBranches.length > 0
     } else if (tip.kind === TipState.Detached) {
       title = `On ${tip.currentSha.substr(0, 7)}`
       tooltip = 'Currently on a detached HEAD'
@@ -163,10 +162,6 @@ export class BranchDropdown extends React.Component<IBranchDropdownProps> {
       return null
     }
 
-    if (!enablePRIntegration()) {
-      return null
-    }
-
     return <PullRequestBadge number={pr.number} status={pr.status} />
   }
 }

app/src/ui/toolbar/dropdown.tsx

@@ -145,6 +145,10 @@ export class ToolbarDropdown extends React.Component<
     this.state = { clientRect: null }
   }
 
+  private get isOpen() {
+    return this.props.dropdownState === 'open'
+  }
+
   private dropdownIcon(state: DropdownState): OcticonSymbol {
     // @TODO: Remake triangle octicon in a 12px version,
     // right now it's scaled badly on normal dpi monitors.
@@ -249,6 +253,13 @@ export class ToolbarDropdown extends React.Component<
     }
   }
 
+  private onFoldoutKeyDown = (event: React.KeyboardEvent<HTMLElement>) => {
+    if (!event.defaultPrevented && this.isOpen && event.key === 'Escape') {
+      event.preventDefault()
+      this.props.onDropdownStateChanged('closed', 'keyboard')
+    }
+  }
+
   private renderDropdownContents = (): JSX.Element | null => {
     if (this.props.dropdownState !== 'open') {
       return null
@@ -265,7 +276,11 @@ export class ToolbarDropdown extends React.Component<
           tabIndex={-1}
           onClick={this.handleOverlayClick}
         />
-        <div className="foldout" style={this.getFoldoutStyle()}>
+        <div
+          className="foldout"
+          style={this.getFoldoutStyle()}
+          onKeyDown={this.onFoldoutKeyDown}
+        >
           {this.props.dropdownContentRenderer()}
         </div>
       </div>

app/static/common/ufo-alert.svg

@@ -0,0 +1,12 @@
+<svg width="56" height="61" viewBox="0 0 56 61" xmlns="http://www.w3.org/2000/svg">
+    <title>
+        ufo-alert
+    </title>
+    <g fill="#C9DEF2" fill-rule="nonzero">
+        <path d="M43.324 1.08c8.09 1.42 13.497 9.126 12.078 17.215-1.326 7.57-8.16 12.79-15.66 12.267-3.827 3.423-8.51 4.283-11.832 4.42-.664.03-1.255-.498-.214-1.07 2.043-1.125 3.344-3.464 4.11-6.312-4.31-3.255-6.694-8.752-5.696-14.44C27.53 5.07 35.235-.337 43.324 1.08zm-.44 20.775v-4h-4v4h4zm0-5v-8h-4v8h4zm-23.758 18.33a8.918 8.918 0 0 0-16.62 6.466l2.777 7.14 16.624-6.468-2.778-7.14-.002.002zm3.606 7.89l-17.554 6.83a.5.5 0 0 1-.647-.284l-2.957-7.603c-1.986-5.105.54-10.853 5.646-12.84 5.103-1.986 10.85.542 12.84 5.647l2.96 7.605a.5.5 0 0 1-.287.647z"/>
+        <path d="M5.583 41.92c-1.98-4.183-.11-8.474 4.21-9.61a.5.5 0 0 0-.256-.967C4.6 32.64 2.435 37.61 4.68 42.35a.5.5 0 0 0 .903-.43zm20.197 3.644l-1.24-3.19L3.37 50.61l1.242 3.19 21.168-8.236zm.83.75l-22.1 8.6a.5.5 0 0 1-.648-.285l-1.604-4.125a.5.5 0 0 1 .284-.647l22.1-8.6a.5.5 0 0 1 .648.285l1.604 4.123a.5.5 0 0 1-.285.647z"/>
+        <path d="M23.604 44.037l-9.914 3.857a.5.5 0 1 0 .362.932l9.914-3.857a.5.5 0 0 0-.362-.934zm-1.77 4.136l-12.55 4.883 1.024 1.435 11.742-4.567-.216-1.75zm.94 2.54l-12.466 4.85a.5.5 0 0 1-.588-.174L8.098 53.11a.5.5 0 0 1 .225-.756L22.07 47.01a.5.5 0 0 1 .678.403l.342 2.772a.5.5 0 0 1-.315.527z"/>
+        <path d="M13.34 56.504l-.473-2.38a.5.5 0 1 0-.98.196l.473 2.38a.5.5 0 1 0 .98-.196zm9.738-2.582a.885.885 0 1 0-1.514.918.885.885 0 0 0 1.514-.918zm.855-.518a1.885 1.885 0 0 1-3.223 1.955 1.886 1.886 0 0 1 3.223-1.957z"/>
+        <path d="M14.078 57.922a.885.885 0 1 0-1.514.918.885.885 0 0 0 1.514-.918zm.855-.518a1.885 1.885 0 1 1-3.223 1.955 1.886 1.886 0 0 1 3.223-1.957zM22.03 52.937l-1.26-2.074a.5.5 0 1 0-.853.52l1.26 2.073a.5.5 0 1 0 .853-.52z"/>
+    </g>
+</svg>

app/styles/_variables.scss

@@ -174,7 +174,7 @@
 
   --toolbar-background-color: $gray-900;
   --toolbar-text-color: $white;
-  --toolbar-text-secondary-color: $gray-400;
+  --toolbar-text-secondary-color: $gray-300;
 
   --toolbar-button-color: var(--toolbar-text-color);
   --toolbar-button-background-color: transparent;

app/styles/mixins/_textboxish.scss

@@ -14,18 +14,23 @@
   padding: 0 var(--spacing-half);
 
   &:focus {
-    outline: none;
-    border-color: var(--focus-color);
-    box-shadow: 0 0 0 1px var(--text-field-focus-shadow-color);
+    @include textboxish-focus-styles;
   }
 }
 
-// This is kept separate from textboxish because we need to be able
-// to apply it conditionally when running on Windows, the disabled
-// styles on macOS are fine.
+@mixin textboxish-focus-styles {
+  outline: none;
+  border-color: var(--focus-color);
+  box-shadow: 0 0 0 1px var(--text-field-focus-shadow-color);
+}
+
+@mixin textboxish-disabled-styles {
+  background: var(--box-alt-background-color);
+  color: var(--text-secondary-color);
+}
+
 @mixin textboxish-disabled {
   &:disabled {
-    background: var(--box-alt-background-color);
-    color: var(--text-secondary-color);
+    @include textboxish-disabled-styles;
   }
 }

app/styles/ui/_author-input.scss

@@ -1,9 +1,13 @@
+@import '../mixins';
+
 .author-input-component {
+  &.disabled .CodeMirror {
+    @include textboxish-disabled-styles;
+  }
+
   .CodeMirror {
-    border: 1px solid var(--box-border-color);
-    border-radius: var(--border-radius);
-    font-size: var(--font-size);
-    font-family: var(--font-family-sans-serif);
+    @include textboxish;
+
     border-top-left-radius: 0;
     border-top-right-radius: 0;
     border-top: 0;
@@ -53,9 +57,7 @@
   }
 
   .CodeMirror-focused {
-    outline: none;
-    border-color: var(--focus-color);
-    box-shadow: 0 0 0 1px var(--text-field-focus-shadow-color);
+    @include textboxish-focus-styles;
     border-top-width: 1px;
     border-top-style: solid;
     margin-top: -1px;

app/styles/ui/_blank-slate.scss

@@ -82,16 +82,33 @@
   .callout:not(:last-child) {
     border-right: var(--base-border);
   }
+
+  // Custom image sizing explicitly for the dedicated
+  // blank slate view (a.k.a the no-repositories view).
+  .blankslate-image {
+    max-width: 400px;
+    width: 80%;
+    flex-grow: 0.6;
+    // Background image url is set in react since we need to
+    // calculate it at runtime.
+    background-repeat: no-repeat;
+    background-position: center bottom;
+    background-size: contain;
+  }
 }
 
-.blankslate-image {
-  width: 80%;
-  flex-grow: 0.6;
-  // Background image url is set in react since we need to
-  // calculate it at runtime.
-  background-repeat: no-repeat;
-  background-position: center bottom;
-  background-size: contain;
+// For all views other than the dedicated blank slate
+// view. Yes, this is confusing.
+.ui-view:not(#blank-slate) .blankslate-image {
+  width: 50%;
+  min-width: 400px;
+  max-width: 800px;
+}
+
+// In the foldout we want the image to fill the
+// full width of the container (minus padding).
+.foldout .blankslate-image {
+  width: 100%;
 }
 
 // When there's not enough space to show the blankslate