Test BlobWorker in browser

Author: andywer

.gitignore

@@ -1,5 +1,6 @@
 .cache/
 .vscode/
+bundle/
 docs/_site
 docs/vendor
 dist/*

package-lock.json

@@ -15,9 +15,11 @@
     "build": "run-p build:cjs build:es",
     "build:cjs": "tsc -p tsconfig.json",
     "build:es": "tsc -p tsconfig-esm.json",
+    "postbuild": "run-s bundle",
+    "bundle": "rollup -c -f umd --file=bundle/worker.js --name=threads --silent -- dist-esm/worker/bundle-entry.js",
     "test": "run-s test:ava test:puppeteer:basic test:puppeteer:webpack",
     "test:ava": "cross-env TS_NODE_FILES=true ava",
-    "test:puppeteer:basic": "puppet-run --plugin=mocha --bundle=./test/workers/:/workers/ ./test/*.chromium*.ts",
+    "test:puppeteer:basic": "puppet-run --plugin=mocha --bundle=./test/workers/:/workers/ --serve=./bundle/worker.js:/worker.js ./test/*.chromium*.ts",
     "test:puppeteer:webpack": "puppet-run --serve ./test/webpack/dist.web/0.worker.js --serve ./test/webpack/dist.web/1.worker.js --plugin=mocha ./test/webpack/webpack.chromium.mocha.ts",
     "posttest": "tslint --project .",
     "prepare": "run-s build"
@@ -79,7 +81,7 @@
     "ts-node": "^8.1.0",
     "tslint": "^5.16.0",
     "tslint-config-prettier": "^1.18.0",
-    "typescript": "^3.4.5",
+    "typescript": "^3.9.3",
     "wavy": "^1.0.4",
     "webpack": "^4.32.2",
     "worker-plugin": "^3.1.0"

package.json

@@ -0,0 +1,14 @@
+const commonjs = require("rollup-plugin-commonjs")
+const nodeResolve = require("rollup-plugin-node-resolve")
+
+module.exports = {
+  plugins: [
+    nodeResolve({
+      browser: true,
+      mainFields: ["module", "main"],
+      preferBuiltins: true
+    }),
+
+    commonjs()
+  ]
+};

rollup.config.js

@@ -0,0 +1,9 @@
+import { expose } from "./index"
+export * from "./index"
+
+if (typeof global !== "undefined") {
+  (global as any).expose = expose
+}
+if (typeof self !== "undefined") {
+  (self as any).expose = expose
+}

src/worker/bundle-entry.ts

@@ -1,8 +1,13 @@
+/*
+ * This code here will be run in a headless Chromium browser using `puppet-run`.
+ * Check the package.json scripts `test:puppeteer:*`.
+ */
+
 import { expect } from "chai"
-import { spawn, Thread } from "../"
+import { spawn, BlobWorker, Thread } from "../"
 
 // We need this as a work-around to make our threads Worker global, since
-// the Parcel bundler would otherwise not recognize `new Worker()` as a web worker
+// the bundler would otherwise not recognize `new Worker()` as a web worker
 import "../src/master/register"
 
 describe("threads in browser", function() {
@@ -20,4 +25,22 @@ describe("threads in browser", function() {
     await Thread.terminate(increment)
   })
 
+  it("can spawn and use a blob worker", async function() {
+    const baseUrl = new URL(window.location.href).origin
+    const workerSource = `
+      // Makes expose() available on global scope
+      importScripts(${JSON.stringify(baseUrl + "/worker.js")})
+
+      let counter = 0
+
+      expose(function() {
+        return ++counter
+      })
+    `
+    const increment = await spawn<() => number>(BlobWorker.fromText(workerSource))
+    expect(await increment()).to.equal(1)
+    expect(await increment()).to.equal(2)
+    expect(await increment()).to.equal(3)
+    await Thread.terminate(increment)
+  })
 })

test/spawn.chromium.mocha.ts

@@ -21,10 +21,10 @@ function replaceArrayBufferWithPlaceholder<In extends any>(obj: In, arrayBuffer:
   } else if (Array.isArray(obj)) {
     return (obj as any[]).map(element => replaceArrayBufferWithPlaceholder(element, arrayBuffer)) as any
   } else if (obj && typeof obj === "object") {
-    const result: typeof obj = Object.create(Object.getPrototypeOf(obj))
+    const result: In = Object.create(Object.getPrototypeOf(obj))
 
     for (const key of Object.getOwnPropertyNames(obj)) {
-      result[key] = replaceArrayBufferWithPlaceholder(obj[key], arrayBuffer)
+      (result as any)[key] = replaceArrayBufferWithPlaceholder((obj as any)[key], arrayBuffer)
     }
     return result as any
   } else {