development/github-desktop
development/github-desktop
1
0
Fork 0
mirror of https://github.com/desktop/desktop synced 2024-08-28 20:51:16 +00:00
Code Issues Packages Projects Releases Wiki Activity

Merge pull request #11935 from desktop/hunk-expansion-type-refactor

Browse source 
Diff expansion, part V: refactor how we compute hunk expansion info
This commit is contained in:
Sergio Padrino 2021-04-07 12:06:49 +02:00 committed by GitHub
parent d449d4ff16 ea52207a48
commit 0a84307187
No known key found for this signature in database
GPG key ID: 4AEE18F83AFDEB23
6 changed files with 129 additions and 77 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

14
app/src/lib/diff-parser.ts
View file

@ -6,6 +6,7 @@ import {
DiffLineType,
} from '../models/diff'
import { assertNever } from '../lib/fatal-error'
import { getHunkHeaderExpansionType } from '../ui/diff/text-diff-expansion'
// https://en.wikipedia.org/wiki/Diff_utility
//
@ -280,7 +281,11 @@ export class DiffParser {
* have no real meaning in the context of a diff and
* are only used to aid the app in line-selections.
*/
private parseHunk(linesConsumed: number): DiffHunk {
private parseHunk(
linesConsumed: number,
hunkIndex: number,
previousHunk: DiffHunk | null
): DiffHunk {
const headerLine = this.readLine()
if (!headerLine) {
throw new Error('Expected hunk header but reached end of diff')
@ -366,7 +371,8 @@ export class DiffParser {
header,
lines,
linesConsumed,
linesConsumed + lines.length - 1
linesConsumed + lines.length - 1,
getHunkHeaderExpansionType(hunkIndex, header, previousHunk)
)
}
@ -397,10 +403,12 @@ export class DiffParser {
const hunks = new Array<DiffHunk>()
let linesConsumed = 0
let previousHunk: DiffHunk | null = null
do {
const hunk = this.parseHunk(linesConsumed)
const hunk = this.parseHunk(linesConsumed, hunks.length, previousHunk)
hunks.push(hunk)
previousHunk = hunk
linesConsumed += hunk.lines.length
} while (this.peek())

29
app/src/models/diff/raw-diff.ts
View file

@ -1,5 +1,31 @@
import { DiffLine } from './diff-line'
export enum DiffHunkExpansionType {
/** The hunk header cannot be expanded at all. */
None = 'None',
/**
* The hunk header can be expanded up exclusively. Only the first hunk can be
* expanded up exclusively.
*/
Up = 'Up',
/**
* The hunk header can be expanded down exclusively. Only the last hunk (if
* it's the dummy hunk with only one line) can be expanded down exclusively.
*/
Down = 'Down',
/** The hunk header can be expanded both up and down. */
Both = 'Both',
/**
* The hunk header represents a short gap that, when expanded, will
* result in merging this hunk and the hunk above.
*/
Short = 'Short',
}
/** each diff is made up of a number of hunks */
export class DiffHunk {
/**
@ -12,7 +38,8 @@ export class DiffHunk {
public readonly header: DiffHunkHeader,
public readonly lines: ReadonlyArray<DiffLine>,
public readonly unifiedDiffStart: number,
public readonly unifiedDiffEnd: number
public readonly unifiedDiffEnd: number,
public readonly expansionType: DiffHunkExpansionType
) {}
}

4
app/src/ui/diff/diff-helpers.tsx
View file

@ -8,6 +8,7 @@ import {
WorkingDirectoryFileChange,
CommittedFileChange,
} from '../../models/status'
import { DiffHunkExpansionType } from '../../models/diff/raw-diff'
/**
* DiffRowType defines the different types of
@ -181,6 +182,9 @@ interface IDiffRowHunk {
* The actual contents of the line.
*/
readonly content: string
/** How the hunk can be expanded. */
readonly expansionType: DiffHunkExpansionType
}
export type DiffRow =

6
app/src/ui/diff/side-by-side-diff.tsx
View file

@ -864,7 +864,11 @@ function getDiffRowsFromHunk(
}
if (line.type === DiffLineType.Hunk) {
rows.push({ type: DiffRowType.Hunk, content: line.content })
rows.push({
type: DiffRowType.Hunk,
content: line.content,
expansionType: hunk.expansionType,
})
continue
}

130
app/src/ui/diff/text-diff-expansion.ts
View file

@ -1,5 +1,7 @@
import { enableTextDiffExpansion } from '../../lib/feature-flag'
import {
DiffHunk,
DiffHunkExpansionType,
DiffHunkHeader,
DiffLine,
DiffLineType,
@ -12,24 +14,6 @@ export const DiffExpansionStep = 20
/** Type of expansion: could be up or down. */
export type ExpansionKind = 'up' | 'down'
/** Interface to represent the expansion capabilities of a hunk header. */
interface IHunkHeaderExpansionInfo {
/** True if the hunk header can be expanded down. */
readonly isExpandableDown: boolean
/** True if the hunk header can be expanded up. */
readonly isExpandableUp: boolean
/** True if the hunk header can be expanded both up and down. */
readonly isExpandableBoth: boolean
/**
* True if the hunk header represents a short gap that, when expanded, will
* result in merging this hunk and the hunk above.
*/
readonly isExpandableShort: boolean
}
/** Builds the diff text string given a list of hunks. */
function getDiffTextFromHunks(hunks: ReadonlyArray<DiffHunk>) {
// Grab all hunk lines and rebuild the diff text from it
@ -70,7 +54,18 @@ function mergeDiffHunks(hunk1: DiffHunk, hunk2: DiffHunk): DiffHunk {
[newFirstHunkLine, ...allHunk1LinesButFirst, ...allHunk2LinesButFirst],
hunk1.unifiedDiffStart,
// This -1 represents the header line of the second hunk that we removed
hunk2.unifiedDiffEnd - 1
hunk2.unifiedDiffEnd - 1,
// The expansion type of the resulting hunk will match the expansion type
// of the first hunk:
// - If the first hunk can be expanded up, it means it's the very first
// hunk, so the resulting hunk will be the first too.
// - If the first hunk can be expanded but short, that doesn't change after
// merging it with the second one.
// - If it can be expanded up and down (meaning it's a long gap), that
// doesn't change after merging it with the second one.
// - It can never be expanded down exclusively, because only the last dummy
// hunk can do that, and that will never be the first hunk in a merge.
hunk1.expansionType
)
}
@ -79,24 +74,24 @@ function mergeDiffHunks(hunk1: DiffHunk, hunk2: DiffHunk): DiffHunk {
* the space represented by the hunk header is short and expansion there would
* mean merging with the hunk above.
*
* @param hunks All hunks in the diff.
* @param hunk The specific hunk for which we want to know the expansion info.
* @param hunkIndex Index of the hunk to evaluate within the whole diff.
* @param hunkHeader Header of the hunk to evaluate.
* @param previousHunk Hunk previous to the one to evaluate. Null if the
* evaluated hunk is the first one.
*/
export function getHunkHeaderExpansionInfo(
hunks: ReadonlyArray<DiffHunk>,
hunk: DiffHunk
): IHunkHeaderExpansionInfo {
let isExpandableDown = false
let isExpandableUp = false
let isExpandableBoth = false
let isExpandableShort = false
export function getHunkHeaderExpansionType(
hunkIndex: number,
hunkHeader: DiffHunkHeader,
previousHunk: DiffHunk | null
): DiffHunkExpansionType {
if (!enableTextDiffExpansion()) {
return DiffHunkExpansionType.None
}
const hunkIndex = hunks.indexOf(hunk)
const previousHunk = hunks[hunkIndex - 1]
const distanceToPrevious =
previousHunk === undefined
previousHunk === null
? Infinity
: hunk.header.oldStartLine -
: hunkHeader.oldStartLine -
previousHunk.header.oldStartLine -
previousHunk.header.oldLineCount
@ -108,21 +103,15 @@ export function getHunkHeaderExpansionInfo(
// short and therefore the direction of expansion doesn't matter.
if (hunkIndex === 0) {
// The top hunk can only be expanded if there is content above it
isExpandableUp =
hunk.header.oldStartLine > 1 && hunk.header.newStartLine > 1
} else if (hunkIndex === hunks.length - 1 && hunk.lines.length === 1) {
isExpandableDown = true
if (hunkHeader.oldStartLine > 1 && hunkHeader.newStartLine > 1) {
return DiffHunkExpansionType.Up
} else {
return DiffHunkExpansionType.None
}
} else if (distanceToPrevious <= DiffExpansionStep) {
isExpandableShort = true
return DiffHunkExpansionType.Short
} else {
isExpandableBoth = true
}
return {
isExpandableDown,
isExpandableUp,
isExpandableBoth,
isExpandableShort,
return DiffHunkExpansionType.Both
}
}
@ -270,12 +259,20 @@ export function expandTextDiffHunk(
let numberOfNewDiffLines = updatedHunkLines.length - hunk.lines.length
const previousHunk = hunkIndex === 0 ? null : diff.hunks[hunkIndex - 1]
const expansionType = getHunkHeaderExpansionType(
hunkIndex,
newHunkHeader,
previousHunk
)
// Update the hunk with all the new info (header, lines, start/end...)
let updatedHunk = new DiffHunk(
newHunkHeader,
updatedHunkLines,
hunk.unifiedDiffStart,
hunk.unifiedDiffEnd + numberOfNewDiffLines
hunk.unifiedDiffEnd + numberOfNewDiffLines,
expansionType
)
let previousHunksEndIndex = 0 // Exclusive
@ -312,17 +309,33 @@ export function expandTextDiffHunk(
const followingHunks =
newHunkLastLine >= newContentLines.length
? []
: diff.hunks
.slice(followingHunksStartIndex)
.map(
hunk =>
new DiffHunk(
hunk.header,
hunk.lines,
hunk.unifiedDiffStart + numberOfNewDiffLines,
hunk.unifiedDiffEnd + numberOfNewDiffLines
)
: diff.hunks.slice(followingHunksStartIndex).map((hunk, hunkIndex) => {
const isLastDummyHunk =
hunkIndex + followingHunksStartIndex === diff.hunks.length - 1 &&
hunk.lines.length === 1 &&
hunk.lines[0].type === DiffLineType.Hunk
// Only compute the new expansion type if the hunk is the first one
// (of the remaining hunks) and it's not the last dummy hunk.
const shouldComputeNewExpansionType =
hunkIndex === 0 && !isLastDummyHunk
return new DiffHunk(
hunk.header,
hunk.lines,
hunk.unifiedDiffStart + numberOfNewDiffLines,
hunk.unifiedDiffEnd + numberOfNewDiffLines,
// If it's the first hunk after the one we expanded, recalculate
// its expansion type.
shouldComputeNewExpansionType
? getHunkHeaderExpansionType(
followingHunksStartIndex,
hunk.header,
updatedHunk
)
: hunk.expansionType
)
})
// Create the new list of hunks of the diff, and the new diff text
const newHunks = [...previousHunks, updatedHunk, ...followingHunks]
@ -386,7 +399,8 @@ export function getTextDiffWithBottomDummyHunk(
dummyHeader,
[dummyLine],
lastHunk.unifiedDiffEnd + 1,
lastHunk.unifiedDiffEnd + 1
lastHunk.unifiedDiffEnd + 1,
DiffHunkExpansionType.Down
)
const newHunks = [...hunks, dummyHunk]

23
app/src/ui/diff/text-diff.tsx
View file

@ -8,6 +8,7 @@ import {
DiffSelection,
DiffLine,
ITextDiff,
DiffHunkExpansionType,
} from '../../models/diff'
import {
WorkingDirectoryFileChange,
@ -50,7 +51,6 @@ import { canSelect } from './diff-helpers'
import {
expandTextDiffHunk,
ExpansionKind,
getHunkHeaderExpansionInfo,
getTextDiffWithBottomDummyHunk,
} from './text-diff-expansion'
import { createOcticonElement } from '../octicons/octicon'
@ -338,6 +338,7 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
/** The current, active, diff gutter selection if any */
private selection: ISelection | null = null
/** The content lines of the "new" file */
private newContentLines: ReadonlyArray<string> | null = null
/** Whether a particular range should be highlighted due to hover */
@ -909,7 +910,7 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
) {
const marker = lineInfo.gutterMarkers[diffGutterName]
if (marker instanceof HTMLElement) {
this.updateGutterMarker(marker, hunks, hunk, diffLine)
this.updateGutterMarker(marker, hunk, diffLine)
}
} else {
batchedOps.push(() => {
@ -949,7 +950,6 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
}
private getGutterLineClassNameInfo(
hunks: ReadonlyArray<DiffHunk>,
hunk: DiffHunk,
diffLine: DiffLine
): { [className: string]: boolean } {
@ -962,10 +962,6 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
isIncludeable &&
diffLine.originalLineNumber !== null &&
inSelection(this.hunkHighlightRange, diffLine.originalLineNumber)
const hunkExpansionInfo =
enableTextDiffExpansion() && diffLine.type === DiffLineType.Hunk
? getHunkHeaderExpansionInfo(hunks, hunk)
: undefined
return {
'diff-line-gutter': true,
@ -976,10 +972,10 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
'read-only': this.props.readOnly,
'diff-line-selected': isIncluded,
'diff-line-hover': hover,
'expandable-down': hunkExpansionInfo?.isExpandableDown === true,
'expandable-up': hunkExpansionInfo?.isExpandableUp === true,
'expandable-both': hunkExpansionInfo?.isExpandableBoth === true,
'expandable-short': hunkExpansionInfo?.isExpandableShort === true,
'expandable-down': hunk.expansionType === DiffHunkExpansionType.Down,
'expandable-up': hunk.expansionType === DiffHunkExpansionType.Up,
'expandable-both': hunk.expansionType === DiffHunkExpansionType.Both,
'expandable-short': hunk.expansionType === DiffHunkExpansionType.Short,
includeable: isIncludeable && !this.props.readOnly,
}
}
@ -1074,7 +1070,7 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
)
}
this.updateGutterMarker(marker, hunks, hunk, diffLine)
this.updateGutterMarker(marker, hunk, diffLine)
return marker
}
@ -1157,11 +1153,10 @@ export class TextDiff extends React.Component<ITextDiffProps, ITextDiffState> {
private updateGutterMarker(
marker: HTMLElement,
hunks: ReadonlyArray<DiffHunk>,
hunk: DiffHunk,
diffLine: DiffLine
) {
const classNameInfo = this.getGutterLineClassNameInfo(hunks, hunk, diffLine)
const classNameInfo = this.getGutterLineClassNameInfo(hunk, diffLine)
for (const [className, include] of Object.entries(classNameInfo)) {
if (include) {
marker.classList.add(className)