vfs: integrate with CJS and ESM module loaders

lib/internal/modules/cjs/loader.js

@@ -113,6 +113,7 @@ const kFormat = Symbol('kFormat');
 
 // Set first due to cycle with ESM loader functions.
 module.exports = {
+  clearStatCache,
   kModuleSource,
   kModuleExport,
   kModuleExportNames,
@@ -155,14 +156,14 @@ const {
 } = internalBinding('contextify');
 
 const assert = require('internal/assert');
-const fs = require('fs');
 const path = require('path');
-const internalFsBinding = internalBinding('fs');
 const { safeGetenv } = internalBinding('credentials');
 const {
   getCjsConditions,
   getCjsConditionsArray,
   initializeCjsConditions,
+  loaderReadFile,
+  loaderStat,
   loadBuiltinModule,
   makeRequireFunction,
   setHasStartedUserCJSExecution,
@@ -272,14 +273,24 @@ function stat(filename) {
     const result = statCache.get(filename);
     if (result !== undefined) { return result; }
   }
-  const result = internalFsBinding.internalModuleStat(filename);
+  const result = loaderStat(filename);
   if (statCache !== null && result >= 0) {
     // Only set cache when `internalModuleStat(filename)` succeeds.
     statCache.set(filename, result);
   }
   return result;
 }
 
+/**
+ * Clear the stat cache. Called when VFS instances are unmounted
+ * to prevent stale stat results from being returned.
+ */
+function clearStatCache() {
+  if (statCache !== null) {
+    statCache = new SafeMap();
+  }
+}
+
 let _stat = stat;
 ObjectDefineProperty(Module, '_stat', {
   __proto__: null,
@@ -1201,7 +1212,7 @@ function defaultLoadImpl(filename, format) {
     case 'module-typescript':
     case 'commonjs-typescript':
     case 'typescript': {
-      return fs.readFileSync(filename, 'utf8');
+      return loaderReadFile(filename, 'utf8');
     }
     case 'builtin':
       return null;

lib/internal/modules/esm/get_format.js

@@ -10,7 +10,6 @@ const {
 } = primordials;
 const { getOptionValue } = require('internal/options');
 const { getValidatedPath } = require('internal/fs/utils');
-const fsBindings = internalBinding('fs');
 const { internal: internalConstants } = internalBinding('constants');
 
 const extensionFormatMap = {
@@ -59,7 +58,8 @@ function mimeToFormat(mime) {
  */
 function getFormatOfExtensionlessFile(url) {
   const path = getValidatedPath(url);
-  switch (fsBindings.getFormatOfExtensionlessFile(path)) {
+  const { loaderGetFormatOfExtensionlessFile } = require('internal/modules/helpers');
+  switch (loaderGetFormatOfExtensionlessFile(path)) {
     case internalConstants.EXTENSIONLESS_FORMAT_WASM:
       return 'wasm';
     default:

lib/internal/modules/esm/load.js

@@ -9,7 +9,7 @@ const {
 
 const { defaultGetFormat } = require('internal/modules/esm/get_format');
 const { validateAttributes, emitImportAssertionWarning } = require('internal/modules/esm/assert');
-const fs = require('fs');
+const { loaderReadFile } = require('internal/modules/helpers');
 
 const { Buffer: { from: BufferFrom } } = require('buffer');
 
@@ -34,11 +34,7 @@ function getSourceSync(url, context) {
   const responseURL = href;
   let source;
   if (protocol === 'file:') {
-    // If you are reading this code to figure out how to patch Node.js module loading
-    // behavior - DO NOT depend on the patchability in new code: Node.js
-    // internals may stop going through the JavaScript fs module entirely.
-    // Prefer module.registerHooks() or other more formal fs hooks released in the future.
-    source = fs.readFileSync(url);
+    source = loaderReadFile(url);
   } else if (protocol === 'data:') {
     const result = dataURLProcessor(url);
     if (result === 'failure') {

lib/internal/modules/esm/resolve.js

@@ -9,7 +9,6 @@ const {
   ObjectPrototypeHasOwnProperty,
   RegExpPrototypeExec,
   RegExpPrototypeSymbolReplace,
-  SafeMap,
   SafeSet,
   String,
   StringPrototypeEndsWith,
@@ -23,16 +22,13 @@ const {
   encodeURIComponent,
 } = primordials;
 const assert = require('internal/assert');
-const internalFS = require('internal/fs/utils');
 const { BuiltinModule } = require('internal/bootstrap/realm');
-const fs = require('fs');
 const { getOptionValue } = require('internal/options');
 // Do not eagerly grab .manifest, it may be in TDZ
 const { sep, posix: { relative: relativePosixPath }, resolve } = require('path');
 const { URL, pathToFileURL, fileURLToPath, isURL, URLParse } = require('internal/url');
 const { getCWDURL, setOwnProperty } = require('internal/util');
 const { canParse: URLCanParse } = internalBinding('url');
-const { legacyMainResolve: FSLegacyMainResolve } = internalBinding('fs');
 const {
   ERR_INPUT_TYPE_NOT_ALLOWED,
   ERR_INVALID_ARG_TYPE,
@@ -49,7 +45,7 @@ const {
 const { defaultGetFormatWithoutErrors } = require('internal/modules/esm/get_format');
 const { getConditionsSet } = require('internal/modules/esm/utils');
 const packageJsonReader = require('internal/modules/package_json_reader');
-const internalFsBinding = internalBinding('fs');
+const { loaderLegacyMainResolve, loaderStat, toRealPath } = require('internal/modules/helpers');
 
 /**
  * @typedef {import('internal/modules/esm/package_config.js').PackageConfig} PackageConfig
@@ -149,8 +145,6 @@ function emitLegacyIndexDeprecation(url, path, pkgPath, base, main) {
   }
 }
 
-const realpathCache = new SafeMap();
-
 const legacyMainResolveExtensions = [
   '',
   '.js',
@@ -198,7 +192,7 @@ function legacyMainResolve(packageJSONUrl, packageConfig, base) {
 
   const baseStringified = isURL(base) ? base.href : base;
 
-  const resolvedOption = FSLegacyMainResolve(pkgPath, packageConfig.main, baseStringified);
+  const resolvedOption = loaderLegacyMainResolve(pkgPath, packageConfig.main, baseStringified);
 
   const maybeMain = resolvedOption <= legacyMainResolveExtensionsIndexes.kResolvedByMainIndexNode ?
     packageConfig.main || './' : '';
@@ -244,7 +238,7 @@ function finalizeResolution(resolved, base, preserveSymlinks) {
     throw err;
   }
 
-  const stats = internalFsBinding.internalModuleStat(
+  const stats = loaderStat(
     StringPrototypeEndsWith(path, '/') ? StringPrototypeSlice(path, -1) : path,
   );
 
@@ -273,13 +267,7 @@ function finalizeResolution(resolved, base, preserveSymlinks) {
   }
 
   if (!preserveSymlinks) {
-    // If you are reading this code to figure out how to patch Node.js module loading
-    // behavior - DO NOT depend on the patchability in new code: Node.js
-    // internals may stop going through the JavaScript fs module entirely.
-    // Prefer module.registerHooks() or other more formal fs hooks released in the future.
-    const real = fs.realpathSync(path, {
-      [internalFS.realpathCacheKey]: realpathCache,
-    });
+    const real = toRealPath(path);
     const { search, hash } = resolved;
     resolved =
         pathToFileURL(real + (StringPrototypeEndsWith(path, sep) ? '/' : ''));