merge main 0c28dc7 into feat/voice-outlines

build/registerVue.js

@@ -1,5 +1,8 @@
-import { register } from 'node:module';
+import { registerHooks } from 'node:module';
+import { load } from './vueLoader.js';
 
 // Lets Node import single-file components: `node --import=<this file>`.
-// Hosts reach it as `<core package>/build/register-vue`.
-register('./vueLoader.js', import.meta.url);
+// Hosts reach it as `<core package>/build/register-vue`. The hooks run on the
+// loading thread: off-thread hooks (module.register) would add a round trip
+// to every module a test imports, not only the components.
+registerHooks({ load });

build/vueLoader.js

@@ -1,14 +1,32 @@
-import { readFile } from 'node:fs/promises';
+import { createHash, randomBytes } from 'node:crypto';
+import {
+  lstatSync,
+  mkdirSync,
+  readFileSync,
+  renameSync,
+  rmSync,
+  writeFileSync,
+} from 'node:fs';
+import { createRequire } from 'node:module';
+import { tmpdir } from 'node:os';
+import path from 'node:path';
 import { fileURLToPath } from 'node:url';
-import { compileScript, compileTemplate, parse } from 'vue/compiler-sfc';
 import { VUE_TEMPLATE_OPTIONS } from './vueOptions.js';
 
+const require = createRequire(import.meta.url);
+
+// The compiler loads on the first component that is not cached, so a test
+// process that imports no views, or only cached ones, never pays for it.
+let compiler = null;
+const sfcCompiler = () => (compiler ??= require('vue/compiler-sfc'));
+
 /**
  * Compile a single-file component to an ES module for Node, so unit tests (the
  * application's and a host's) can import components without a bundler.
  * Styles are dropped: tests read the global stylesheet separately.
  */
 export function compileVueModule(source, filename) {
+  const { compileScript, compileTemplate, parse } = sfcCompiler();
   // The template is parsed with the SFC; parse it as the browser build does.
   const { descriptor, errors } = parse(source, {
     filename,
@@ -40,14 +58,113 @@ export function compileVueModule(source, filename) {
   return `${script}\n${template}\nif (typeof render === 'function') __sfc__.render = render;\nexport default __sfc__;\n`;
 }
 
-/** Node module hook: load `.vue` files as compiled modules. */
-export async function load(url, context, nextLoad) {
+// The loader's own code is part of every key, so a change to how components
+// compile never reuses output from before it.
+let loaderFingerprint = null;
+const fingerprint = () =>
+  (loaderFingerprint ??= createHash('sha256')
+    .update(readFileSync(fileURLToPath(import.meta.url)))
+    .update(readFileSync(new URL('./vueOptions.js', import.meta.url)))
+    .update(require('vue/package.json').version)
+    .digest('hex'));
+
+/**
+ * Where compiled components are kept between test processes, never a
+ * package's own tree (a host's checks refuse files inside Core): the system
+ * temp directory, or on Windows the per-user local app data directory, since
+ * a temp directory there may be shared and its ownership is not checked.
+ * GEV_VUE_CACHE=0 compiles every time.
+ */
+export function vueCacheDirectory(
+  env = process.env,
+  platform = process.platform,
+) {
+  if (env.GEV_VUE_CACHE === '0') return null;
+  if (platform === 'win32') {
+    return env.LOCALAPPDATA ? path.join(env.LOCALAPPDATA, 'gev-vue-sfc') : null;
+  }
+  return path.join(tmpdir(), `gev-vue-sfc-${process.getuid()}`);
+}
+
+/** The cache entry for one component: its path, its text and the loader. */
+export function vueCacheKey(source, filename) {
+  return createHash('sha256')
+    .update(JSON.stringify([fingerprint(), filename]))
+    .update('\0')
+    .update(source)
+    .digest('hex');
+}
+
+/**
+ * Compile a component, reusing a previous process's result for the same text.
+ * A cache that cannot be read or written only costs the compile.
+ */
+export function cachedVueModule(
+  source,
+  filename,
+  directory = vueCacheDirectory(),
+) {
+  if (!directory || !ownCacheDirectory(directory)) {
+    return compileVueModule(source, filename);
+  }
+  const entry = path.join(directory, `${vueCacheKey(source, filename)}.mjs`);
+  try {
+    return readFileSync(entry, 'utf8');
+  } catch {
+    // Not compiled yet.
+  }
+  const compiled = compileVueModule(source, filename);
+  // Concurrent test processes and threads may compile the same component;
+  // each writes its own new file and the rename makes the entry appear whole.
+  const partial = `${entry}.${randomBytes(6).toString('hex')}.tmp`;
+  try {
+    writeFileSync(partial, compiled, { flag: 'wx', mode: 0o600 });
+    renameSync(partial, entry);
+  } catch {
+    // An unwritable directory, or a rename another process holds open,
+    // leaves the cache without this entry.
+    try {
+      rmSync(partial, { force: true });
+    } catch {
+      // A partial file that cannot be removed is only clutter.
+    }
+  }
+  return compiled;
+}
+
+/**
+ * Cached modules run as code, so the directory must be this user's own: a
+ * real directory (not a link), owned by the current user and writable by no
+ * one else. In a shared temp directory another user could otherwise create it
+ * first and plant modules. On Windows it sits in the user's own profile.
+ */
+const checkedDirectories = new Map();
+export function ownCacheDirectory(directory) {
+  if (!checkedDirectories.has(directory)) {
+    checkedDirectories.set(directory, isOwnDirectory(directory));
+  }
+  return checkedDirectories.get(directory);
+}
+
+function isOwnDirectory(directory) {
+  try {
+    mkdirSync(directory, { recursive: true, mode: 0o700 });
+    const stats = lstatSync(directory);
+    if (!stats.isDirectory()) return false;
+    if (process.platform === 'win32') return true;
+    return stats.uid === process.getuid() && (stats.mode & 0o022) === 0;
+  } catch {
+    return false;
+  }
+}
+
+/** Synchronous module hook (module.registerHooks): `.vue` loads compiled. */
+export function load(url, context, nextLoad) {
   if (!url.endsWith('.vue')) return nextLoad(url, context);
   const filename = fileURLToPath(url);
-  const source = await readFile(filename, 'utf8');
   return {
     format: 'module',
-    source: compileVueModule(source, filename),
+    source: cachedVueModule(readFileSync(filename, 'utf8'), filename),
     shortCircuit: true,
   };
 }