Add bundle loader (denoland/deno_std#480)

Original: fe7f6e117f

bundle/README.md

@@ -0,0 +1,16 @@
+# bundle
+
+These are modules that help support bundling with Deno.
+
+## Usage
+
+The main usage is to load and run bundles. For example, to run a bundle named
+`bundle.js` in your current working directory:
+
+```sh
+deno run https://deno.land/std/bundle/run.ts bundle.js
+```
+
+---
+
+Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.

bundle/run.ts

@@ -0,0 +1,11 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { evaluate, instantiate, load } from "./utils.ts";
+
+async function main(args: string[]): Promise<void> {
+  const text = await load(args);
+  const result = evaluate(text);
+  instantiate(...result);
+}
+
+main(Deno.args);

bundle/test.ts

@@ -0,0 +1,111 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { test } from "../testing/mod.ts";
+import {
+  assert,
+  AssertionError,
+  assertStrictEq,
+  assertThrowsAsync
+} from "../testing/asserts.ts";
+import { assertEquals } from "../testing/pretty.ts";
+import { evaluate, instantiate, load, ModuleMetaData } from "./utils.ts";
+
+/* eslint-disable @typescript-eslint/no-namespace */
+declare global {
+  namespace globalThis {
+    var __results: [string, string] | undefined;
+  }
+}
+/* eslint-enable @typescript-eslint/no-namespace */
+
+const fixture = `
+define("data", [], { "baz": "qat" });
+define("modB", ["require", "exports", "data"], function(require, exports, data) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  exports.foo = "bar";
+  exports.baz = data.baz;
+});
+define("modA", ["require", "exports", "modB"], function(require, exports, modB) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  globalThis.__results = [modB.foo, modB.baz];
+});
+`;
+
+const fixtureQueue = ["data", "modB", "modA"];
+const fixtureModules = new Map<string, ModuleMetaData>();
+fixtureModules.set("data", {
+  dependencies: [],
+  factory: {
+    baz: "qat"
+  },
+  exports: {}
+});
+fixtureModules.set("modB", {
+  dependencies: ["require", "exports", "data"],
+  factory(_require, exports, data): void {
+    "use strict";
+    Object.defineProperty(exports, "__esModule", { value: true });
+    exports.foo = "bar";
+    exports.baz = data.baz;
+  },
+  exports: {}
+});
+fixtureModules.set("modA", {
+  dependencies: ["require", "exports", "modB"],
+  factory(_require, exports, modB): void {
+    "use strict";
+    Object.defineProperty(exports, "__esModule", { value: true });
+    globalThis.__results = [modB.foo, modB.baz];
+  },
+  exports: {}
+});
+
+test(async function loadBundle(): Promise<void> {
+  const result = await load(["", "./bundle/testdata/bundle.js"]);
+  assert(result != null);
+  assert(
+    result.includes(
+      `define("subdir/print_hello", ["require", "exports"], function(`
+    )
+  );
+});
+
+test(async function loadBadArgs(): Promise<void> {
+  await assertThrowsAsync(
+    async (): Promise<void> => {
+      await load(["bundle/test.ts"]);
+    },
+    AssertionError,
+    "Expected exactly two arguments."
+  );
+});
+
+test(async function loadMissingBundle(): Promise<void> {
+  await assertThrowsAsync(
+    async (): Promise<void> => {
+      await load([".", "bad_bundle.js"]);
+    },
+    AssertionError,
+    `Expected "bad_bundle.js" to exist.`
+  );
+});
+
+test(async function evaluateBundle(): Promise<void> {
+  assert(globalThis.define == null, "Expected 'define' to be undefined");
+  const [queue, modules] = evaluate(fixture);
+  assert(globalThis.define == null, "Expected 'define' to be undefined");
+  assertEquals(queue, ["data", "modB", "modA"]);
+  assert(modules.has("modA"));
+  assert(modules.has("modB"));
+  assert(modules.has("data"));
+  assertStrictEq(modules.size, 3);
+});
+
+test(async function instantiateBundle(): Promise<void> {
+  assert(globalThis.__results == null);
+  instantiate(fixtureQueue, fixtureModules);
+  assertEquals(globalThis.__results, ["bar", "qat"]);
+  delete globalThis.__results;
+});

bundle/testdata/bundle.js

@@ -0,0 +1,67 @@
+define("subdir/print_hello", ["require", "exports"], function(
+  require,
+  exports
+) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  function printHello() {
+    console.log("Hello");
+  }
+  exports.printHello = printHello;
+});
+define("subdir/subdir2/mod2", [
+  "require",
+  "exports",
+  "subdir/print_hello"
+], function(require, exports, print_hello_ts_1) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  function returnsFoo() {
+    return "Foo";
+  }
+  exports.returnsFoo = returnsFoo;
+  function printHello2() {
+    print_hello_ts_1.printHello();
+  }
+  exports.printHello2 = printHello2;
+});
+define("subdir/mod1", ["require", "exports", "subdir/subdir2/mod2"], function(
+  require,
+  exports,
+  mod2_ts_1
+) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  function returnsHi() {
+    return "Hi";
+  }
+  exports.returnsHi = returnsHi;
+  function returnsFoo2() {
+    return mod2_ts_1.returnsFoo();
+  }
+  exports.returnsFoo2 = returnsFoo2;
+  function printHello3() {
+    mod2_ts_1.printHello2();
+  }
+  exports.printHello3 = printHello3;
+  function throwsError() {
+    throw Error("exception from mod1");
+  }
+  exports.throwsError = throwsError;
+});
+define("005_more_imports", ["require", "exports", "subdir/mod1"], function(
+  require,
+  exports,
+  mod1_ts_1
+) {
+  "use strict";
+  Object.defineProperty(exports, "__esModule", { value: true });
+  mod1_ts_1.printHello3();
+  if (mod1_ts_1.returnsHi() !== "Hi") {
+    throw Error("Unexpected");
+  }
+  if (mod1_ts_1.returnsFoo2() !== "Foo") {
+    throw Error("Unexpected");
+  }
+});
+//# sourceMappingURL=data:application/json;base64,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

bundle/utils.ts

@@ -0,0 +1,108 @@
+// Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
+
+import { assertStrictEq, assert } from "../testing/asserts.ts";
+import { exists } from "../fs/exists.ts";
+
+export interface DefineFactory {
+  /* eslint-disable-next-line @typescript-eslint/no-explicit-any */
+  (...args: any): object | void;
+}
+
+export interface ModuleMetaData {
+  dependencies: string[];
+  factory?: DefineFactory | object;
+  exports: object;
+}
+
+type Define = (
+  id: string,
+  dependencies: string[],
+  factory: DefineFactory
+) => void;
+
+/* eslint-disable @typescript-eslint/no-namespace */
+declare global {
+  namespace globalThis {
+    var define: Define | undefined;
+  }
+}
+/* eslint-enable @typescript-eslint/no-namespace */
+
+/** Evaluate the bundle, returning a queue of module IDs and their data to
+ * instantiate.
+ */
+export function evaluate(
+  text: string
+): [string[], Map<string, ModuleMetaData>] {
+  const queue: string[] = [];
+  const modules = new Map<string, ModuleMetaData>();
+
+  globalThis.define = function define(
+    id: string,
+    dependencies: string[],
+    factory: DefineFactory
+  ): void {
+    modules.set(id, {
+      dependencies,
+      factory,
+      exports: {}
+    });
+    queue.push(id);
+  };
+  // eslint-disable-next-line @typescript-eslint/no-explicit-any
+  (Deno as any).core.evalContext(text);
+  // Deleting `define()` so it isn't accidentally there when the modules
+  // instantiate.
+  delete globalThis.define;
+
+  return [queue, modules];
+}
+
+/** Drain the queue of module IDs while instantiating the modules. */
+export function instantiate(
+  queue: string[],
+  modules: Map<string, ModuleMetaData>
+): void {
+  let id: string | undefined;
+  while ((id = queue.shift())) {
+    const module = modules.get(id)!;
+    assert(module != null);
+    assert(module.factory != null);
+
+    const dependencies = module.dependencies.map(
+      (id): object => {
+        if (id === "require") {
+          // TODO(kitsonk) support dynamic import by passing a `require()` that
+          // can return a local module or dynamically import one.
+          return (): void => {};
+        } else if (id === "exports") {
+          return module.exports;
+        }
+        const dep = modules.get(id)!;
+        assert(dep != null);
+        return dep.exports;
+      }
+    );
+
+    if (typeof module.factory === "function") {
+      module.factory!(...dependencies);
+    } else if (module.factory) {
+      // when bundling JSON, TypeScript just emits it as an object/array as the
+      // third argument of the `define()`.
+      module.exports = module.factory;
+    }
+    delete module.factory;
+  }
+}
+
+/** Load the bundle and return the contents asynchronously. */
+export async function load(args: string[]): Promise<string> {
+  // TODO(kitsonk) allow loading of remote bundles via fetch.
+  assertStrictEq(args.length, 2, "Expected exactly two arguments.");
+  const [, bundleFileName] = args;
+  assert(
+    await exists(bundleFileName),
+    `Expected "${bundleFileName}" to exist.`
+  );
+  return new TextDecoder().decode(await Deno.readFile(bundleFileName));
+}

test.ts

@@ -2,6 +2,7 @@
 // Copyright 2018-2019 the Deno authors. All rights reserved. MIT license.
 import "./archive/tar_test.ts";
 import "./bytes/test.ts";
+import "./bundle/test.ts";
 import "./colors/test.ts";
 import "./datetime/test.ts";
 import "./encoding/test.ts";