[New] no-rename-default: Forbid importing a default export by a different name

CHANGELOG.md

@@ -11,6 +11,7 @@ This change log adheres to standards from [Keep a CHANGELOG](https://keepachange
 - [`dynamic-import-chunkname`]: Allow empty chunk name when webpackMode: 'eager' is set; add suggestions to remove name in eager mode ([#3004], thanks [@amsardesai])
 - [`no-unused-modules`]: Add `ignoreUnusedTypeExports` option ([#3011], thanks [@silverwind])
 - add support for Flat Config ([#3018], thanks [@michaelfaith])
+- [`no-rename-default`]: Forbid importing a default export by a different name ([#3006], thanks [@whitneyit])
 
 ### Fixed
 - [`no-extraneous-dependencies`]: allow wrong path ([#3012], thanks [@chabb])

README.md

@@ -37,6 +37,7 @@ This plugin intends to support linting of ES2015+ (ES6+) import/export syntax, a
 | [no-mutable-exports](docs/rules/no-mutable-exports.md)                 | Forbid the use of mutable exports with `var` or `let`.                                |      |       |    |    |    |    |
 | [no-named-as-default](docs/rules/no-named-as-default.md)               | Forbid use of exported name as identifier of default export.                          |      | ☑️ 🚸 |    |    |    |    |
 | [no-named-as-default-member](docs/rules/no-named-as-default-member.md) | Forbid use of exported name as property of default export.                            |      | ☑️ 🚸 |    |    |    |    |
+| [no-rename-default](docs/rules/no-rename-default.md)                   | Forbid importing a default export by a different name.                                |      |       |    |    |    |    |
 | [no-unused-modules](docs/rules/no-unused-modules.md)                   | Forbid modules without exports, or exports without matching import in another module. |      |       |    |    |    |    |
 
 ### Module systems

docs/rules/no-rename-default.md

@@ -0,0 +1,29 @@
+# import/no-rename-default
+
+<!-- end auto-generated rule header -->
+
+Prohibit importing a default export by another name.
+
+## Rule Details
+
+Given:
+
+```js
+// api/get-users.js
+export default async function getUsers() {}
+```
+
+...this would be valid:
+
+```js
+import getUsers from './api/get-users.js';
+```
+
+...and the following would be reported:
+
+```js
+// Caution: `get-users.js` has a default export `getUsers`.
+// This imports `getUsers` as `findUsers`.
+// Check if you meant to write `import getUsers from './api/get-users'` instead.
+import findUsers from './get-users';
+```

src/exportMap/builder.js

@@ -195,6 +195,7 @@ export default class ExportMapBuilder {
       && exportMap.namespace.size > 0 // anything is exported
       && !exportMap.namespace.has('default') // and default isn't added already
     ) {
+      exportMap.exports.set('default', {});
       exportMap.namespace.set('default', {}); // add default export
     }
 

src/exportMap/index.js

@@ -14,6 +14,7 @@ export default class ExportMap {
      * @type {Map<string, () => ExportMap>}
      */
     this.imports = new Map();
+    this.exports = new Map();
     this.errors = [];
     /**
      * type {'ambiguous' | 'Module' | 'Script'}

src/exportMap/specifier.js

@@ -9,15 +9,18 @@ export default function processSpecifier(specifier, astNode, exportMap, namespac
       local = 'default';
       break;
     case 'ExportNamespaceSpecifier':
+      exportMap.exports.set(specifier.exported.name, astNode);
       exportMap.namespace.set(specifier.exported.name, Object.defineProperty(exportMeta, 'namespace', {
         get() { return namespace.resolveImport(nsource); },
       }));
       return;
     case 'ExportAllDeclaration':
+      exportMap.exports.set(specifier.exported.name || specifier.exported.value, astNode);
       exportMap.namespace.set(specifier.exported.name || specifier.exported.value, namespace.add(exportMeta, specifier.source.value));
       return;
     case 'ExportSpecifier':
       if (!astNode.source) {
+        exportMap.exports.set(specifier.exported.name || specifier.exported.value, astNode);
         exportMap.namespace.set(specifier.exported.name || specifier.exported.value, namespace.add(exportMeta, specifier.local));
         return;
       }

src/exportMap/visitor.js

@@ -53,6 +53,7 @@ export default class ImportExportVisitorBuilder {
         if (astNode.declaration.type === 'Identifier') {
           this.namespace.add(exportMeta, astNode.declaration);
         }
+        this.exportMap.exports.set('default', astNode);
         this.exportMap.namespace.set('default', exportMeta);
       },
       ExportAllDeclaration() {
@@ -86,13 +87,17 @@ export default class ImportExportVisitorBuilder {
             case 'TSInterfaceDeclaration':
             case 'TSAbstractClassDeclaration':
             case 'TSModuleDeclaration':
+              this.exportMap.exports.set(astNode.declaration.id.name, astNode);
               this.exportMap.namespace.set(astNode.declaration.id.name, captureDoc(this.source, this.docStyleParsers, astNode));
               break;
             case 'VariableDeclaration':
               astNode.declaration.declarations.forEach((d) => {
                 recursivePatternCapture(
                   d.id,
-                  (id) => this.exportMap.namespace.set(id.name, captureDoc(this.source, this.docStyleParsers, d, astNode)),
+                  (id) => {
+                    this.exportMap.exports.set(id.name, astNode);
+                    this.exportMap.namespace.set(id.name, captureDoc(this.source, this.docStyleParsers, d, astNode));
+                  },
                 );
               });
               break;
@@ -126,18 +131,21 @@ export default class ImportExportVisitorBuilder {
     ));
     if (exportedDecls.length === 0) {
       // Export is not referencing any local declaration, must be re-exporting
+      this.exportMap.exports.set('default', astNode);
       this.exportMap.namespace.set('default', captureDoc(this.source, this.docStyleParsers, astNode));
       return;
     }
     if (
       this.isEsModuleInteropTrue // esModuleInterop is on in tsconfig
       && !this.exportMap.namespace.has('default') // and default isn't added already
     ) {
+      this.exportMap.exports.set('default', {}); // add default export
       this.exportMap.namespace.set('default', {}); // add default export
     }
     exportedDecls.forEach((decl) => {
       if (decl.type === 'TSModuleDeclaration') {
         if (decl.body && decl.body.type === 'TSModuleDeclaration') {
+          this.exportMap.exports.set(decl.body.id.name, astNode);
           this.exportMap.namespace.set(decl.body.id.name, captureDoc(this.source, this.docStyleParsers, decl.body));
         } else if (decl.body && decl.body.body) {
           decl.body.body.forEach((moduleBlockNode) => {
@@ -150,20 +158,19 @@ export default class ImportExportVisitorBuilder {
             if (!namespaceDecl) {
               // TypeScript can check this for us; we needn't
             } else if (namespaceDecl.type === 'VariableDeclaration') {
-              namespaceDecl.declarations.forEach((d) => recursivePatternCapture(d.id, (id) => this.exportMap.namespace.set(
-                id.name,
-                captureDoc(this.source, this.docStyleParsers, decl, namespaceDecl, moduleBlockNode),
-              )),
-              );
+              namespaceDecl.declarations.forEach((d) => recursivePatternCapture(d.id, (id) => {
+                this.exportMap.exports.set(id.name, astNode);
+                this.exportMap.namespace.set(id.name, captureDoc(this.source, this.docStyleParsers, decl, namespaceDecl, moduleBlockNode));
+              }));
             } else {
-              this.exportMap.namespace.set(
-                namespaceDecl.id.name,
-                captureDoc(this.source, this.docStyleParsers, moduleBlockNode));
+              this.exportMap.exports.set(namespaceDecl.id.name, astNode);
+              this.exportMap.namespace.set(namespaceDecl.id.name, captureDoc(this.source, this.docStyleParsers, moduleBlockNode));
             }
           });
         }
       } else {
         // Export as default
+        this.exportMap.exports.set('default', {});
         this.exportMap.namespace.set('default', captureDoc(this.source, this.docStyleParsers, decl));
       }
     });

src/index.js

@@ -22,6 +22,7 @@ export const rules = {
   'no-named-as-default': require('./rules/no-named-as-default'),
   'no-named-as-default-member': require('./rules/no-named-as-default-member'),
   'no-anonymous-default-export': require('./rules/no-anonymous-default-export'),
+  'no-rename-default': require('./rules/no-rename-default'),
   'no-unused-modules': require('./rules/no-unused-modules'),
 
   'no-commonjs': require('./rules/no-commonjs'),