Test with Vitest: @ffmpeg/core in Node.js, @ffmpeg/ffmpeg and @ffmpeg/util in Chromium

- vitest.config.js has a project per package and core: core-st and core-mt
  run the core in Node.js, where exec() may block; browser-st and
  browser-mt run the FFmpeg class and util in cross-origin isolated
  Chromium (Vitest browser mode with Playwright)
- tests/helpers: fixtures for a core or loaded FFmpeg per file and an empty
  directory per test, and a Vite plugin for HTTP edge cases
- the core is also built for Node.js, and its ESM build is marked as a
  module
- CI runs the core tests on Node.js 22, 24 and 26 and the browser tests
  once
- the old mocha-headless-chrome suite is removed

Author: lucasgelfond

.github/workflows/CI.yml

@@ -56,28 +56,55 @@ jobs:
           name: ffmpeg-core-mt
           path: packages/core-mt/dist/*
   tests:
+    # Node 22 (the oldest LTS release), 24 and 26.
     runs-on: ubuntu-latest
-    needs:
-      - build-core
-      - build-core-mt
+    needs: [build-core, build-core-mt]
+    strategy:
+      matrix:
+        node: [22, 24, 26]
     steps:
-      - name: Checkout Source Code
-        uses: actions/checkout@v2
-      - name: Download ffmpeg-core
-        uses: actions/download-artifact@v4
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - uses: actions/download-artifact@v4
+        with:
+          name: ffmpeg-core
+          path: packages/core/dist
+      - uses: actions/download-artifact@v4
+        with:
+          name: ffmpeg-core-mt
+          path: packages/core-mt/dist
+      - uses: pnpm/action-setup@v6
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ matrix.node }}
+          cache: pnpm
+      - run: pnpm install --frozen-lockfile
+      - run: pnpm test --project core-st --project core-mt
+  browser:
+    # @ffmpeg/ffmpeg and @ffmpeg/util in Chromium.
+    runs-on: ubuntu-latest
+    needs: [build-core, build-core-mt]
+    strategy:
+      matrix:
+        node: [22, 24, 26]
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - uses: actions/download-artifact@v4
         with:
           name: ffmpeg-core
           path: packages/core/dist
-      - name: Download ffmpeg-core-mt
-        uses: actions/download-artifact@v4
+      - uses: actions/download-artifact@v4
         with:
           name: ffmpeg-core-mt
           path: packages/core-mt/dist
       - uses: pnpm/action-setup@v6
-      - name: Use Node.js 24
-        uses: actions/setup-node@v4
+      - uses: actions/setup-node@v4
         with:
-          node-version: 24.x
+          node-version: ${{ matrix.node }}
           cache: pnpm
-      - name: Install dependencies
-        run: pnpm install --frozen-lockfile
+      - run: pnpm install --frozen-lockfile
+      - run: pnpm test:install
+      - run: pnpm test --project browser-st --project browser-mt

Dockerfile

@@ -198,7 +198,8 @@ RUN mkdir -p /src/dist/umd && bash -x /src/build.sh \
 RUN mkdir -p /src/dist/esm && bash -x /src/build.sh \
       ${FFMPEG_LIBS} \
       -sEXPORT_ES6 \
-      -o dist/esm/ffmpeg-core.js
+      -o dist/esm/ffmpeg-core.js && \
+    echo '{"type": "module"}' > dist/esm/package.json
 
 # Export ffmpeg-core.wasm to dist/, use `docker buildx build -o . .` to get assets
 FROM scratch AS exportor

apps/vanilla-app/package.json

@@ -4,7 +4,7 @@
   "description": "browser example",
   "private": true,
   "scripts": {
-    "download": "node ../../scripts/download-assets.js",
+    "download": "node ../../scripts/download-assets.cjs",
     "prestart": "pnpm download",
     "start": "node server.js"
   },

build/ffmpeg-wasm.sh

@@ -30,7 +30,7 @@ CONF_FLAGS=(
   -lswscale 
   -Wno-deprecated-declarations 
   $LDFLAGS 
-  -sENVIRONMENT=worker
+  -sENVIRONMENT=web,worker,node           # node: the core tests run in Node.js
   -sWASM_BIGINT                            # enable big int support
   -sDEFAULT_TO_CXX                         # x265, zimg and harfbuzz are C++
   -sUSE_SDL=2                              # use emscripten SDL2 lib port

package.json

@@ -1,6 +1,7 @@
 {
   "name": "root",
   "private": true,
+  "type": "module",
   "packageManager": "pnpm@12.6.0",
   "engines": {
     "node": ">=22"
@@ -10,9 +11,14 @@
     "build": "pnpm -r --filter './packages/*' build",
     "build:wasm": "bash scripts/build-wasm.sh",
     "prepublishOnly": "pnpm build",
-    "postinstall": "pnpm build"
+    "postinstall": "pnpm build",
+    "pretest": "pnpm build",
+    "test": "vitest run",
+    "test:install": "playwright install --with-deps chromium"
   },
   "devDependencies": {
+    "@ffmpeg/ffmpeg": "workspace:*",
+    "@ffmpeg/util": "workspace:*",
     "@vitest/browser-playwright": "^5.0.2",
     "playwright": "^1.63.0",
     "vitest": "^5.0.2"