fix(ngcc): correctly identify relative Windows-style import paths (#36372)

Previously, `isRelativePath()` assumed paths are *nix-style. This caused
Windows-style paths (such as `C:\foo\some-package\some-file.js`) to not
be recognized as "relative" imports.

This commit fixes this by using the OS-agnostic `isRooted()` helper and
also accounting for both styles of path delimiters: `/` and `\`

PR Close #36372

packages/compiler-cli/ngcc/src/utils.ts

@@ -7,7 +7,7 @@
  */
 import * as ts from 'typescript';
 
-import {absoluteFrom, AbsoluteFsPath, FileSystem} from '../../src/ngtsc/file_system';
+import {absoluteFrom, AbsoluteFsPath, FileSystem, isRooted} from '../../src/ngtsc/file_system';
 import {KnownDeclaration} from '../../src/ngtsc/reflection';
 
 /**
@@ -85,10 +85,11 @@ export type PathMappings = {
 /**
  * Test whether a path is "relative".
  *
- * Relative paths start with `/`, `./` or `../`; or are simply `.` or `..`.
+ * Relative paths start with `/`, `./` or `../` (or the Windows equivalents); or are simply `.` or
+ * `..`.
  */
 export function isRelativePath(path: string): boolean {
-  return /^\/|^\.\.?($|\/)/.test(path);
+  return isRooted(path) || /^\.\.?(\/|\\|$)/.test(path);
 }
 
 /**

packages/compiler-cli/ngcc/test/dependencies/module_resolver_spec.ts

@@ -67,16 +67,29 @@ runInEachFileSystem(() => {
       ]);
     });
 
-    describe('resolveModule()', () => {
+    describe('resolveModuleImport()', () => {
       describe('with relative paths', () => {
         it('should resolve sibling, child and aunt modules', () => {
           const resolver = new ModuleResolver(getFileSystem());
+
+          // With relative file paths.
           expect(resolver.resolveModuleImport('./x', _('/libs/local-package/index.js')))
               .toEqual(new ResolvedRelativeModule(_('/libs/local-package/x.js')));
           expect(resolver.resolveModuleImport('./sub-folder', _('/libs/local-package/index.js')))
               .toEqual(new ResolvedRelativeModule(_('/libs/local-package/sub-folder/index.js')));
           expect(resolver.resolveModuleImport('../x', _('/libs/local-package/sub-folder/index.js')))
               .toEqual(new ResolvedRelativeModule(_('/libs/local-package/x.js')));
+
+          // With absolute file paths.
+          expect(resolver.resolveModuleImport(
+                     _('/libs/local-package/x'), _('/libs/local-package/index.js')))
+              .toEqual(new ResolvedRelativeModule(_('/libs/local-package/x.js')));
+          expect(resolver.resolveModuleImport(
+                     _('/libs/local-package/sub-folder'), _('/libs/local-package/index.js')))
+              .toEqual(new ResolvedRelativeModule(_('/libs/local-package/sub-folder/index.js')));
+          expect(resolver.resolveModuleImport(
+                     _('/libs/local-package/x'), _('/libs/local-package/sub-folder/index.js')))
+              .toEqual(new ResolvedRelativeModule(_('/libs/local-package/x.js')));
         });
 
         it('should return `null` if the resolved module relative module does not exist', () => {

packages/compiler-cli/ngcc/test/utils_spec.ts

@@ -7,6 +7,8 @@
  */
 
 import * as ts from 'typescript';
+import {absoluteFrom as _abs} from '../../src/ngtsc/file_system';
+import {runInEachFileSystem} from '../../src/ngtsc/file_system/testing';
 import {KnownDeclaration} from '../../src/ngtsc/reflection';
 import {FactoryMap, getTsHelperFnFromDeclaration, getTsHelperFnFromIdentifier, isRelativePath, stripExtension} from '../src/utils';
 
@@ -167,19 +169,24 @@ describe('getTsHelperFnFromIdentifier()', () => {
   });
 });
 
+runInEachFileSystem(() => {
   describe('isRelativePath()', () => {
     it('should return true for relative paths', () => {
       expect(isRelativePath('.')).toBe(true);
       expect(isRelativePath('..')).toBe(true);
       expect(isRelativePath('./')).toBe(true);
+      expect(isRelativePath('.\\')).toBe(true);
       expect(isRelativePath('../')).toBe(true);
+      expect(isRelativePath('..\\')).toBe(true);
       expect(isRelativePath('./abc/xyz')).toBe(true);
+      expect(isRelativePath('.\\abc\\xyz')).toBe(true);
       expect(isRelativePath('../abc/xyz')).toBe(true);
+      expect(isRelativePath('..\\abc\\xyz')).toBe(true);
     });
 
     it('should return true for absolute paths', () => {
-    expect(isRelativePath('/')).toBe(true);
-    expect(isRelativePath('/abc/xyz')).toBe(true);
+      expect(isRelativePath(_abs('/'))).toBe(true);
+      expect(isRelativePath(_abs('/abc/xyz'))).toBe(true);
     });
 
     it('should return false for other paths', () => {
@@ -193,6 +200,7 @@ describe('isRelativePath()', () => {
       expect(isRelativePath('@abc/xyz')).toBe(false);
     });
   });
+});
 
 describe('stripExtension()', () => {
   it('should strip the extension from a file name', () => {

packages/compiler-cli/src/ngtsc/file_system/index.ts

@@ -7,7 +7,7 @@
  */
 export {CachedFileSystem} from './src/cached_file_system';
 export {NgtscCompilerHost} from './src/compiler_host';
-export {absoluteFrom, absoluteFromSourceFile, basename, dirname, getFileSystem, isRoot, join, relative, relativeFrom, resolve, setFileSystem} from './src/helpers';
+export {absoluteFrom, absoluteFromSourceFile, basename, dirname, getFileSystem, isRoot, isRooted, join, relative, relativeFrom, resolve, setFileSystem} from './src/helpers';
 export {LogicalFileSystem, LogicalProjectPath} from './src/logical';
 export {NodeJSFileSystem} from './src/node_js_file_system';
 export {AbsoluteFsPath, FileStats, FileSystem, PathSegment, PathString} from './src/types';

packages/compiler-cli/src/ngtsc/file_system/src/helpers.ts

@@ -73,6 +73,13 @@ export function isRoot(path: AbsoluteFsPath): boolean {
   return fs.isRoot(path);
 }
 
+/**
+ * Static access to `isRooted`.
+ */
+export function isRooted(path: string): boolean {
+  return fs.isRooted(path);
+}
+
 /**
  * Static access to `relative`.
  */