Test the Node.js example

CONTRIBUTING.md

@@ -23,14 +23,38 @@ $ rake build:download_prebuilt
 # Build Ruby (if you need to build Ruby by yourself)
 $ rake build:head-wasm32-unknown-wasip1-full
 
-# Build npm package
+# Build and test the WASI Preview 1 npm package
+$ rake npm:ruby-head-wasm-wasi:build
+$ rake npm:ruby-head-wasm-wasi:check
+
+# Build and test the WASI Preview 2 npm package
 $ rake npm:ruby-head-wasm-wasip2:build
-# Test npm package
 $ rake npm:ruby-head-wasm-wasip2:check
 ```
 
 If you need to re-build Ruby, please clean `./rubies` directory, and run `rake npm:ruby-head-wasm-wasi` again.
 
+### npm package test structure
+
+The `ruby-wasm-wasi` package contains the shared JavaScript bindings and test suites, but it does not contain a Ruby WebAssembly binary. Version-specific packages provide the binary and invoke the shared tests with `RUBY_NPM_PACKAGE_ROOT`:
+
+```text
+ruby-head-wasm-wasi
+└─ test
+   ├─ ruby-wasm-wasi:test:run
+   └─ ruby-wasm-wasi:test:node-examples
+
+ruby-4.0-wasm-wasi, ruby-3.x-wasm-wasi
+└─ test
+   └─ ruby-wasm-wasi:test:run
+
+ruby-head-wasm-wasip2
+└─ test
+   └─ ruby-wasm-wasi:test:run
+```
+
+The shared `test:run` script runs the unit, Vitest, and browser E2E suites. The `test:node-examples` script is invoked separately and only by `ruby-head-wasm-wasi` because the Node.js examples use `@ruby/head-wasm-wasi`.
+
 ## Building CRuby from source
 
 If you want to build CRuby for WebAssembly from source yourself, follow the below instructions.

packages/npm-packages/ruby-head-wasm-wasi/package.json

@@ -29,7 +29,7 @@
     "README.md"
   ],
   "scripts": {
-    "test": "RUBY_NPM_PACKAGE_ROOT=../ruby-head-wasm-wasi npm -C ../ruby-wasm-wasi run test:run",
+    "test": "RUBY_NPM_PACKAGE_ROOT=../ruby-head-wasm-wasi npm -C ../ruby-wasm-wasi run test:run && RUBY_NPM_PACKAGE_ROOT=../ruby-head-wasm-wasi npm -C ../ruby-wasm-wasi run test:node-examples",
     "build:deps": "cd ../ruby-wasm-wasi && npm run build",
     "build:static:files": "../ruby-wasm-wasi/tools/pack-static-files.sh ./dist",
     "build:static:compat": "../ruby-wasm-wasi/tools/pack-compat-shim.mjs --dist=./dist --pkg=ruby-head-wasm-wasi",

packages/npm-packages/ruby-wasm-wasi/package.json

@@ -42,6 +42,7 @@
     "test:run": "npm run test:unit && npm run test:vitest -- --run && npm run test:e2e",
     "test:vitest": "vitest ./test/",
     "test:unit": "./tools/run-test-unit.mjs",
+    "test:node-examples": "vitest ./test-node-examples/ --run",
     "test:e2e": "playwright install && npm run test:e2e:examples && npm run test:e2e:integrations",
     "test:e2e:examples": "playwright test -c test-e2e/playwright.examples.config.ts",
     "test:e2e:integrations": "playwright test -c test-e2e/playwright.integrations.config.ts",

packages/npm-packages/ruby-wasm-wasi/test-node-examples/examples.test.js

@@ -0,0 +1,22 @@
+import { afterEach, beforeEach, describe, expect, test } from "vitest";
+import { setupNodeExampleTest } from "./support.js";
+
+describe("Node.js examples", () => {
+  let context;
+
+  beforeEach(async () => {
+    context = await setupNodeExampleTest();
+  });
+
+  afterEach(async () => {
+    await context?.cleanup();
+  });
+
+  test("index.node.js is healthy", async () => {
+    const { stdout } = await context.run("index.node.js");
+
+    expect(stdout).toMatch(/ruby .* \[wasm32-wasi\]/);
+    expect(stdout).toContain("NoMethodError");
+    expect(stdout).toContain("RuntimeError");
+  }, 70_000);
+});

packages/npm-packages/ruby-wasm-wasi/test-node-examples/support.js

@@ -0,0 +1,41 @@
+import { execFile } from "child_process";
+import fs from "fs/promises";
+import os from "os";
+import path from "path";
+import { promisify } from "util";
+import { fileURLToPath } from "url";
+
+const execFileAsync = promisify(execFile);
+const exampleDir = fileURLToPath(new URL("../example/", import.meta.url));
+
+export const setupNodeExampleTest = async () => {
+  if (!process.env.RUBY_NPM_PACKAGE_ROOT) {
+    throw new Error("RUBY_NPM_PACKAGE_ROOT must be set");
+  }
+
+  const rubyPackageRoot = path.resolve(process.env.RUBY_NPM_PACKAGE_ROOT);
+  const temporaryDir = await fs.mkdtemp(
+    path.join(os.tmpdir(), "ruby-wasm-node-example-"),
+  );
+  const packageLink = path.join(
+    temporaryDir,
+    "node_modules/@ruby/head-wasm-wasi",
+  );
+
+  try {
+    await fs.mkdir(path.dirname(packageLink), { recursive: true });
+    await fs.symlink(rubyPackageRoot, packageLink, "dir");
+  } catch (error) {
+    await fs.rm(temporaryDir, { recursive: true, force: true });
+    throw error;
+  }
+
+  return {
+    run: (exampleFile) =>
+      execFileAsync(process.execPath, [path.join(exampleDir, exampleFile)], {
+        cwd: temporaryDir,
+        timeout: 60_000,
+      }),
+    cleanup: () => fs.rm(temporaryDir, { recursive: true, force: true }),
+  };
+};