esm: require braces for modules code

PR-URL: nodejs#49657
Reviewed-By: Antoine du Hamel <[email protected]>
Reviewed-By: Jacob Smith <[email protected]>

Author: GeoffreyBooth

.eslintrc.js

@@ -53,10 +53,10 @@ module.exports = {
   overrides: [
     {
       files: [
-        'test/es-module/test-esm-type-flag.js',
-        'test/es-module/test-esm-type-flag-alias.js',
         '*.mjs',
         'test/es-module/test-esm-example-loader.js',
+        'test/es-module/test-esm-type-flag.js',
+        'test/es-module/test-esm-type-flag-alias.js',
       ],
       parserOptions: { sourceType: 'module' },
     },
@@ -111,6 +111,14 @@ module.exports = {
         },
       ] },
     },
+    {
+      files: [
+        'lib/internal/modules/**/*.js',
+      ],
+      rules: {
+        'curly': 'error',
+      },
+    },
     {
       files: [
         'lib/internal/test_runner/**/*.js',

lib/internal/modules/cjs/loader.js

@@ -173,7 +173,7 @@ function stat(filename) {
   filename = path.toNamespacedPath(filename);
   if (statCache !== null) {
     const result = statCache.get(filename);
-    if (result !== undefined) return result;
+    if (result !== undefined) { return result; }
   }
   const result = internalModuleStat(filename);
   if (statCache !== null && result >= 0) {
@@ -197,8 +197,9 @@ ObjectDefineProperty(Module, '_stat', {
 
 function updateChildren(parent, child, scan) {
   const children = parent?.children;
-  if (children && !(scan && ArrayPrototypeIncludes(children, child)))
+  if (children && !(scan && ArrayPrototypeIncludes(children, child))) {
     ArrayPrototypePush(children, child);
+  }
 }
 
 function reportModuleToWatchMode(filename) {
@@ -386,13 +387,16 @@ function readPackageScope(checkPath) {
     if (enabledPermission && !permission.has('fs.read', checkPath + sep)) {
       return false;
     }
-    if (StringPrototypeEndsWith(checkPath, sep + 'node_modules'))
+    if (StringPrototypeEndsWith(checkPath, sep + 'node_modules')) {
       return false;
+    }
     const pjson = _readPackage(checkPath + sep);
-    if (pjson.exists) return {
-      data: pjson,
-      path: checkPath,
-    };
+    if (pjson.exists) {
+      return {
+        data: pjson,
+        path: checkPath,
+      };
+    }
   } while (separatorIndex > rootSeparatorIndex);
   return false;
 }
@@ -445,7 +449,7 @@ const realpathCache = new SafeMap();
 // absolute realpath.
 function tryFile(requestPath, isMain) {
   const rc = _stat(requestPath);
-  if (rc !== 0) return;
+  if (rc !== 0) { return; }
   if (getOptionValue('--preserve-symlinks') && !isMain) {
     return path.resolve(requestPath);
   }
@@ -479,15 +483,15 @@ function findLongestRegisteredExtension(filename) {
   let startIndex = 0;
   while ((index = StringPrototypeIndexOf(name, '.', startIndex)) !== -1) {
     startIndex = index + 1;
-    if (index === 0) continue; // Skip dotfiles like .gitignore
+    if (index === 0) { continue; } // Skip dotfiles like .gitignore
     currentExtension = StringPrototypeSlice(name, index);
-    if (Module._extensions[currentExtension]) return currentExtension;
+    if (Module._extensions[currentExtension]) { return currentExtension; }
   }
   return '.js';
 }
 
 function trySelfParentPath(parent) {
-  if (!parent) return false;
+  if (!parent) { return false; }
 
   if (parent.filename) {
     return parent.filename;
@@ -501,7 +505,7 @@ function trySelfParentPath(parent) {
 }
 
 function trySelf(parentPath, request) {
-  if (!parentPath) return false;
+  if (!parentPath) { return false; }
 
   const { data: pkg, path: pkgPath } = readPackageScope(parentPath);
   if (!pkg || pkg.exports == null || pkg.name === undefined) {
@@ -523,8 +527,9 @@ function trySelf(parentPath, request) {
       pathToFileURL(pkgPath + '/package.json'), expansion, pkg,
       pathToFileURL(parentPath), getCjsConditions()), parentPath, pkgPath);
   } catch (e) {
-    if (e.code === 'ERR_MODULE_NOT_FOUND')
+    if (e.code === 'ERR_MODULE_NOT_FOUND') {
       throw createEsmNotFoundErr(request, pkgPath + '/package.json');
+    }
     throw e;
   }
 }
@@ -537,8 +542,7 @@ function resolveExports(nmPath, request) {
   // The implementation's behavior is meant to mirror resolution in ESM.
   const { 1: name, 2: expansion = '' } =
     RegExpPrototypeExec(EXPORTS_PATTERN, request) || kEmptyObject;
-  if (!name)
-    return;
+  if (!name) { return; }
   const pkgPath = path.resolve(nmPath, name);
   const pkg = _readPackage(pkgPath);
   if (pkg.exists && pkg.exports != null) {
@@ -548,8 +552,9 @@ function resolveExports(nmPath, request) {
         pathToFileURL(pkgPath + '/package.json'), '.' + expansion, pkg, null,
         getCjsConditions()), null, pkgPath);
     } catch (e) {
-      if (e.code === 'ERR_MODULE_NOT_FOUND')
+      if (e.code === 'ERR_MODULE_NOT_FOUND') {
         throw createEsmNotFoundErr(request, pkgPath + '/package.json');
+      }
       throw e;
     }
   }
@@ -571,8 +576,9 @@ Module._findPath = function(request, paths, isMain) {
 
   const cacheKey = request + '\x00' + ArrayPrototypeJoin(paths, '\x00');
   const entry = Module._pathCache[cacheKey];
-  if (entry)
+  if (entry) {
     return entry;
+  }
 
   let exts;
   const trailingSlash = request.length > 0 &&
@@ -619,8 +625,9 @@ Module._findPath = function(request, paths, isMain) {
 
     if (!absoluteRequest) {
       const exportsResolved = resolveExports(curPath, request);
-      if (exportsResolved)
+      if (exportsResolved) {
         return exportsResolved;
+      }
     }
 
     const basePath = path.resolve(curPath, request);
@@ -652,16 +659,18 @@ Module._findPath = function(request, paths, isMain) {
 
       if (!filename) {
         // Try it with each of the extensions
-        if (exts === undefined)
+        if (exts === undefined) {
           exts = ObjectKeys(Module._extensions);
+        }
         filename = tryExtensions(basePath, exts, isMain);
       }
     }
 
     if (!filename && rc === 1) {  // Directory.
       // try it with each of the extensions at "index"
-      if (exts === undefined)
+      if (exts === undefined) {
         exts = ObjectKeys(Module._extensions);
+      }
       filename = tryPackage(basePath, exts, isMain, request);
     }
 
@@ -697,8 +706,9 @@ if (isWindows) {
     // path.resolve will make sure from.length >=3 in Windows.
     if (StringPrototypeCharCodeAt(from, from.length - 1) ===
           CHAR_BACKWARD_SLASH &&
-        StringPrototypeCharCodeAt(from, from.length - 2) === CHAR_COLON)
+        StringPrototypeCharCodeAt(from, from.length - 2) === CHAR_COLON) {
       return [from + 'node_modules'];
+    }
 
     const paths = [];
     for (let i = from.length - 1, p = 0, last = from.length; i >= 0; --i) {
@@ -711,11 +721,12 @@ if (isWindows) {
       if (code === CHAR_BACKWARD_SLASH ||
           code === CHAR_FORWARD_SLASH ||
           code === CHAR_COLON) {
-        if (p !== nmLen)
+        if (p !== nmLen) {
           ArrayPrototypePush(
             paths,
             StringPrototypeSlice(from, 0, last) + '\\node_modules',
           );
+        }
         last = i;
         p = 0;
       } else if (p !== -1) {
@@ -736,8 +747,9 @@ if (isWindows) {
     from = path.resolve(from);
     // Return early not only to avoid unnecessary work, but to *avoid* returning
     // an array of two items for a root: [ '//node_modules', '/node_modules' ]
-    if (from === '/')
+    if (from === '/') {
       return ['/node_modules'];
+    }
 
     // note: this approach *only* works when the path is guaranteed
     // to be absolute.  Doing a fully-edge-case-correct path.split
@@ -746,11 +758,12 @@ if (isWindows) {
     for (let i = from.length - 1, p = 0, last = from.length; i >= 0; --i) {
       const code = StringPrototypeCharCodeAt(from, i);
       if (code === CHAR_FORWARD_SLASH) {
-        if (p !== nmLen)
+        if (p !== nmLen) {
           ArrayPrototypePush(
             paths,
             StringPrototypeSlice(from, 0, last) + '/node_modules',
           );
+        }
         last = i;
         p = 0;
       } else if (p !== -1) {
@@ -827,14 +840,15 @@ const CircularRequirePrototypeWarningProxy = new Proxy({}, {
     // Allow __esModule access in any case because it is used in the output
     // of transpiled code to determine whether something comes from an
     // ES module, and is not used as a regular key of `module.exports`.
-    if (prop in target || prop === '__esModule') return target[prop];
+    if (prop in target || prop === '__esModule') { return target[prop]; }
     emitCircularRequireWarning(prop);
     return undefined;
   },
 
   getOwnPropertyDescriptor(target, prop) {
-    if (ObjectPrototypeHasOwnProperty(target, prop) || prop === '__esModule')
+    if (ObjectPrototypeHasOwnProperty(target, prop) || prop === '__esModule') {
       return ObjectGetOwnPropertyDescriptor(target, prop);
+    }
     emitCircularRequireWarning(prop);
     return undefined;
   },
@@ -878,8 +892,9 @@ Module._load = function(request, parent, isMain) {
       const cachedModule = Module._cache[filename];
       if (cachedModule !== undefined) {
         updateChildren(parent, cachedModule, true);
-        if (!cachedModule.loaded)
+        if (!cachedModule.loaded) {
           return getExportsForCircularRequire(cachedModule);
+        }
         return cachedModule.exports;
       }
       delete relativeResolveCache[relResolveCacheIdentifier];
@@ -904,8 +919,9 @@ Module._load = function(request, parent, isMain) {
     updateChildren(parent, cachedModule, true);
     if (!cachedModule.loaded) {
       const parseCachedModule = cjsParseCache.get(cachedModule);
-      if (!parseCachedModule || parseCachedModule.loaded)
+      if (!parseCachedModule || parseCachedModule.loaded) {
         return getExportsForCircularRequire(cachedModule);
+      }
       parseCachedModule.loaded = true;
     } else {
       return cachedModule.exports;
@@ -988,8 +1004,9 @@ Module._resolveFilename = function(request, parent, isMain, options) {
           const lookupPaths = Module._resolveLookupPaths(request, fakeParent);
 
           for (let j = 0; j < lookupPaths.length; j++) {
-            if (!ArrayPrototypeIncludes(paths, lookupPaths[j]))
+            if (!ArrayPrototypeIncludes(paths, lookupPaths[j])) {
               ArrayPrototypePush(paths, lookupPaths[j]);
+            }
           }
         }
       }
@@ -1013,8 +1030,9 @@ Module._resolveFilename = function(request, parent, isMain, options) {
                                 getCjsConditions()), parentPath,
           pkg.path);
       } catch (e) {
-        if (e.code === 'ERR_MODULE_NOT_FOUND')
+        if (e.code === 'ERR_MODULE_NOT_FOUND') {
           throw createEsmNotFoundErr(request);
+        }
         throw e;
       }
     }
@@ -1032,7 +1050,7 @@ Module._resolveFilename = function(request, parent, isMain, options) {
 
   // Look up the filename first, since that's the cache key.
   const filename = Module._findPath(request, paths, isMain);
-  if (filename) return filename;
+  if (filename) { return filename; }
   const requireStack = [];
   for (let cursor = parent;
     cursor;
@@ -1053,13 +1071,15 @@ Module._resolveFilename = function(request, parent, isMain, options) {
 
 function finalizeEsmResolution(resolved, parentPath, pkgPath) {
   const { encodedSepRegEx } = require('internal/modules/esm/resolve');
-  if (RegExpPrototypeExec(encodedSepRegEx, resolved) !== null)
+  if (RegExpPrototypeExec(encodedSepRegEx, resolved) !== null) {
     throw new ERR_INVALID_MODULE_SPECIFIER(
       resolved, 'must not include encoded "/" or "\\" characters', parentPath);
+  }
   const filename = fileURLToPath(resolved);
   const actual = tryFile(filename);
-  if (actual)
+  if (actual) {
     return actual;
+  }
   const err = createEsmNotFoundErr(filename,
                                    path.resolve(pkgPath, 'package.json'));
   throw err;
@@ -1069,8 +1089,9 @@ function createEsmNotFoundErr(request, path) {
   // eslint-disable-next-line no-restricted-syntax
   const err = new Error(`Cannot find module '${request}'`);
   err.code = 'MODULE_NOT_FOUND';
-  if (path)
+  if (path) {
     err.path = path;
+  }
   // TODO(BridgeAR): Add the requireStack as well.
   return err;
 }
@@ -1085,8 +1106,9 @@ Module.prototype.load = function(filename) {
 
   const extension = findLongestRegisteredExtension(filename);
   // allow .mjs to be overridden
-  if (StringPrototypeEndsWith(filename, '.mjs') && !Module._extensions['.mjs'])
+  if (StringPrototypeEndsWith(filename, '.mjs') && !Module._extensions['.mjs']) {
     throw new ERR_REQUIRE_ESM(filename, true);
+  }
 
   Module._extensions[extension](this, filename);
   this.loaded = true;
@@ -1097,8 +1119,9 @@ Module.prototype.load = function(filename) {
   // Preemptively cache
   if ((module?.module === undefined ||
        module.module.getStatus() < kEvaluated) &&
-      !cascadedLoader.cjsCache.has(this))
+      !cascadedLoader.cjsCache.has(this)) {
     cascadedLoader.cjsCache.set(this, exports);
+  }
 };
 
 // Loads a module at the given file path. Returns that module's
@@ -1233,7 +1256,7 @@ Module.prototype._compile = function(content, filename) {
   const exports = this.exports;
   const thisValue = exports;
   const module = this;
-  if (requireDepth === 0) statCache = new SafeMap();
+  if (requireDepth === 0) { statCache = new SafeMap(); }
   if (inspectorWrapper) {
     result = inspectorWrapper(compiledWrapper, thisValue, exports,
                               require, module, filename, dirname);
@@ -1242,7 +1265,7 @@ Module.prototype._compile = function(content, filename) {
                           [exports, require, module, filename, dirname]);
   }
   hasLoadedAnyUserCJSModule = true;
-  if (requireDepth === 0) statCache = null;
+  if (requireDepth === 0) { statCache = null; }
   return result;
 };
 
@@ -1399,8 +1422,7 @@ Module._initPaths = function() {
 };
 
 Module._preloadModules = function(requests) {
-  if (!ArrayIsArray(requests))
-    return;
+  if (!ArrayIsArray(requests)) { return; }
 
   isPreloading = true;
 
@@ -1416,8 +1438,9 @@ Module._preloadModules = function(requests) {
       throw e;
     }
   }
-  for (let n = 0; n < requests.length; n++)
+  for (let n = 0; n < requests.length; n++) {
     internalRequire(parent, requests[n]);
+  }
   isPreloading = false;
 };