[Fix] importType: fix isExternalModule calculation

CHANGELOG.md

@@ -8,10 +8,12 @@ This change log adheres to standards from [Keep a CHANGELOG](http://keepachangel
 
 ### Fixed
 - [`extensions`]: ignore unresolveable type-only imports ([#2270], [#2271], [@jablko])
+- `importType`: fix `isExternalModule` calculation ([#2282], [@mx-bernhard])
 
 ### Changed
 - [Docs] [`order`]: add type to the default groups ([#2272], [@charpeni])
 - [readme] Add note to TypeScript docs to install appropriate resolver ([#2279], [@johnthagen])
+- [Refactor] `importType`: combine redundant `isScoped` and `isScopedModule` ([@ljharb])
 
 ## [2.25.2] - 2021-10-12
 
@@ -936,6 +938,8 @@ for info on changes for earlier releases.
 
 [`memo-parser`]: ./memo-parser/README.md
 
+[#2282]: https://github.com/import-js/eslint-plugin-import/pull/2282
+[#2279]: https://github.com/import-js/eslint-plugin-import/pull/2279
 [#2272]: https://github.com/import-js/eslint-plugin-import/pull/2272
 [#2271]: https://github.com/import-js/eslint-plugin-import/pull/2271
 [#2270]: https://github.com/import-js/eslint-plugin-import/pull/2270
@@ -1542,6 +1546,7 @@ for info on changes for earlier releases.
 [@MikeyBeLike]: https://github.com/MikeyBeLike
 [@mplewis]: https://github.com/mplewis
 [@mrmckeb]: https://github.com/mrmckeb
+[@mx-bernhard]: https://github.com/mx-bernhard
 [@nickofthyme]: https://github.com/nickofthyme
 [@nicolashenry]: https://github.com/nicolashenry
 [@noelebrun]: https://github.com/noelebrun

src/core/importType.js

@@ -29,7 +29,7 @@ export function isExternalModule(name, settings, path, context) {
   if (arguments.length < 4) {
     throw new TypeError('isExternalModule: name, settings, path, and context are all required');
   }
-  return isModule(name) && isExternalPath(name, settings, path, getContextPackagePath(context));
+  return (isModule(name) || isScoped(name)) && isExternalPath(name, settings, path, getContextPackagePath(context));
 }
 
 export function isExternalModuleMain(name, settings, path, context) {
@@ -101,10 +101,6 @@ function typeTest(name, context, path) {
   return 'unknown';
 }
 
-export function isScopedModule(name) {
-  return name.indexOf('@') === 0 && !name.startsWith('@/');
-}
-
 export default function resolveImportType(name, context) {
   return typeTest(name, context, resolve(name, context));
 }

src/rules/extensions.js

@@ -1,7 +1,7 @@
 import path from 'path';
 
 import resolve from 'eslint-module-utils/resolve';
-import { isBuiltIn, isExternalModule, isScoped, isScopedModule } from '../core/importType';
+import { isBuiltIn, isExternalModule, isScoped } from '../core/importType';
 import moduleVisitor from 'eslint-module-utils/moduleVisitor';
 import docsUrl from '../docsUrl';
 
@@ -131,7 +131,7 @@ module.exports = {
       const slashCount = file.split('/').length - 1;
 
       if (slashCount === 0)  return true;
-      if (isScopedModule(file) && slashCount <= 1) return true;
+      if (isScoped(file) && slashCount <= 1) return true;
       return false;
     }
 
@@ -161,7 +161,7 @@ module.exports = {
         importPath,
         context.settings,
         resolve(importPath, context),
-        context
+        context,
       ) || isScoped(importPath);
 
       if (!extension || !importPath.endsWith(`.${extension}`)) {

tests/src/core/importType.js

@@ -1,7 +1,7 @@
 import { expect } from 'chai';
 import * as path from 'path';
 
-import importType, { isExternalModule, isScopedModule, isScoped } from 'core/importType';
+import importType, { isExternalModule, isScoped } from 'core/importType';
 
 import { testContext, testFilePath } from '../utils';
 
@@ -234,16 +234,19 @@ describe('importType(name)', function () {
   it('`isExternalModule` works with windows directory separator', function () {
     const context = testContext();
     expect(isExternalModule('foo', {}, 'E:\\path\\to\\node_modules\\foo', context)).to.equal(true);
+    expect(isExternalModule('@foo/bar', {}, 'E:\\path\\to\\node_modules\\@foo\\bar', context)).to.equal(true);
     expect(isExternalModule('foo', {
       'import/external-module-folders': ['E:\\path\\to\\node_modules'],
     }, 'E:\\path\\to\\node_modules\\foo', context)).to.equal(true);
   });
 
-  it('correctly identifies scoped modules with `isScopedModule`', () => {
-    expect(isScopedModule('@/abc')).to.equal(false);
-    expect(isScopedModule('@/abc/def')).to.equal(false);
-    expect(isScopedModule('@a/abc')).to.equal(true);
-    expect(isScopedModule('@a/abc/def')).to.equal(true);
+  it('`isExternalModule` works with unix directory separator', function () {
+    const context = testContext();
+    expect(isExternalModule('foo', {}, '/path/to/node_modules/foo', context)).to.equal(true);
+    expect(isExternalModule('@foo/bar', {}, '/path/to/node_modules/@foo/bar', context)).to.equal(true);
+    expect(isExternalModule('foo', {
+      'import/external-module-folders': ['/path/to/node_modules'],
+    }, '/path/to/node_modules/foo', context)).to.equal(true);
   });
 
   it('correctly identifies scoped modules with `isScoped`', () => {