build: speed up golden testing by parallelizing

Speeds up golden testing by parallelizing.

Author: devversion

bazel/api-golden/index_npm_packages.ts

@@ -42,43 +42,54 @@ async function main(
   const entryPoints = findEntryPointsWithinNpmPackage(npmPackageDir, packageJson);
   const outdatedGoldens: string[] = [];
 
-  let allTestsSucceeding = true;
+  const tasks: Promise<boolean>[] = [];
 
   for (const {subpath, typesEntryPointPath} of entryPoints) {
-    // API extractor generates API reports as markdown files. For each types
-    // entry-point we maintain a separate golden file. These golden files are
-    // based on the name of the defining NodeJS exports subpath in the NPM package,
-    // See: https://api-extractor.com/pages/overview/demo_api_report/.
-    const goldenName = path.join(subpath, 'index.api.md');
-    const goldenFilePath = path.join(goldenDir, goldenName);
-    const moduleName = normalizePathToPosix(path.join(packageJson.name, subpath));
-
-    const actual = await testApiGolden(
-      typesEntryPointPath,
-      stripExportPattern,
-      typeNames,
-      packageJsonPath,
-      moduleName,
-    );
+    tasks.push(
+      (async () => {
+        // API extractor generates API reports as markdown files. For each types
+        // entry-point we maintain a separate golden file. These golden files are
+        // based on the name of the defining NodeJS exports subpath in the NPM package,
+        // See: https://api-extractor.com/pages/overview/demo_api_report/.
+        const goldenName = path.join(subpath, 'index.api.md');
+        const goldenFilePath = path.join(goldenDir, goldenName);
+        const moduleName = normalizePathToPosix(path.join(packageJson.name, subpath));
+
+        const actual = await testApiGolden(
+          typesEntryPointPath,
+          stripExportPattern,
+          typeNames,
+          packageJsonPath,
+          moduleName,
+        );
+
+        if (actual === null) {
+          console.error(
+            `Could not generate API golden for subpath: "${subpath}". See errors above.`,
+          );
+          process.exit(1);
+        }
 
-    if (actual === null) {
-      console.error(`Could not generate API golden for subpath: "${subpath}". See errors above.`);
-      process.exit(1);
-    }
-
-    if (approveGolden) {
-      fs.mkdirSync(path.dirname(goldenFilePath), {recursive: true});
-      fs.writeFileSync(goldenFilePath, actual, 'utf8');
-    } else {
-      const expected = fs.readFileSync(goldenFilePath, 'utf8');
-      if (actual !== expected) {
-        // Keep track of outdated goldens for error message.
-        outdatedGoldens.push(goldenName);
-        allTestsSucceeding = false;
-      }
-    }
+        if (approveGolden) {
+          await fs.promises.mkdir(path.dirname(goldenFilePath), {recursive: true});
+          await fs.promises.writeFile(goldenFilePath, actual, 'utf8');
+        } else {
+          const expected = await fs.promises.readFile(goldenFilePath, 'utf8');
+          if (actual !== expected) {
+            // Keep track of outdated goldens for error message.
+            outdatedGoldens.push(goldenName);
+            return false;
+          }
+        }
+
+        return true;
+      })(),
+    );
   }
 
+  const results = await Promise.all(tasks);
+  const allTestsSucceeding = results.every((r) => r === true);
+
   if (outdatedGoldens.length) {
     console.error(chalk.red(`The following goldens are outdated:`));
     outdatedGoldens.forEach((name) => console.info(`-  ${name}`));

bazel/api-golden/test_api_report.ts

@@ -55,7 +55,8 @@ export async function testApiGolden(
   customPackageName: string,
 ): Promise<string | null> {
   const tempDir =
-    process.env.TEST_TMPDIR ?? fs.mkdtempSync(path.join(os.tmpdir(), 'api-golden-rule'));
+    process.env.TEST_TMPDIR ??
+    (await fs.promises.mkdtemp(path.join(os.tmpdir(), 'api-golden-rule')));
   const rjsMode = process.env['RJS_MODE'] === 'true';
 
   let resolvedTypePackages: Awaited<ReturnType<typeof resolveTypePackages>> | null = null;
@@ -144,8 +145,8 @@ export async function testApiGolden(
   if (!result.succeeded) {
     return null;
   }
-  const reportOut = fs.readFileSync(reportTmpOutPath, 'utf8');
-  fs.rmSync(reportTmpOutPath);
+  const reportOut = await fs.promises.readFile(reportTmpOutPath, 'utf8');
+  await fs.promises.rm(reportTmpOutPath);
   return reportOut;
 }