fixup! fix(@angular/build): strip all vite id prefixes from minified code with external dependencies

Author: alan-agius4

packages/angular/build/src/tools/vite/plugins/id-prefix-plugin.ts

@@ -29,17 +29,7 @@ export function createRemoveIdPrefixPlugin(externals: string[]): Plugin {
         return;
       }
 
-      // The path suffix is bounded so that a match can never extend past the end of an
-      // import specifier string literal. With a greedy `.+`, minified (single-line) code
-      // would let the first match consume the remainder of the line, leaving all later
-      // `/@id/` occurrences on that line unstripped.
-      const escapedExternals = externals.map(
-        (e) => escapeRegexSpecialChars(e) + '(?:/[^\'"`\\s]+)?',
-      );
-      const prefixedExternalRegex = new RegExp(
-        `${resolvedConfig.base}${VITE_ID_PREFIX}(${escapedExternals.join('|')})`,
-        'g',
-      );
+      const transformFn = createTransformer(resolvedConfig.base, externals);
 
       // @ts-expect-error: Property 'push' does not exist on type 'readonly Plugin<any>[]'
       // Reasoning:
@@ -48,15 +38,34 @@ export function createRemoveIdPrefixPlugin(externals: string[]): Plugin {
       //  AFTER the import-analysis.
       resolvedConfig.plugins.push({
         name: 'angular-plugin-remove-id-prefix-transform',
-        transform: (code: string) => {
-          // don't do anything when code does not contain the Vite prefix
-          if (!code.includes(VITE_ID_PREFIX)) {
-            return code;
-          }
-
-          return code.replace(prefixedExternalRegex, (_, externalName) => externalName);
-        },
+        transform: transformFn,
       });
     },
   };
 }
+
+/**
+ * Creates a transform function that removes the Vite ID prefix from externals.
+ * @param base The base path of the application.
+ * @param externals The external package names.
+ * @returns A function that transforms code by removing the Vite ID prefix.
+ */
+export function createTransformer(base: string, externals: string[]): (code: string) => string {
+  // The path suffix is bounded so that a match can never extend past the end of an
+  // import specifier string literal. With a greedy `.+`, minified (single-line) code
+  // would let the first match consume the remainder of the line, leaving all later
+  // `/@id/` occurrences on that line unstripped.
+  const escapedExternals = externals.map((e) => escapeRegexSpecialChars(e) + '(?:/[^\'"`\\s]+)?');
+
+  const prefixedExternalRegex = new RegExp(
+    `${base}${VITE_ID_PREFIX}(${escapedExternals.join('|')})`,
+    'g',
+  );
+
+  return (code: string) => {
+    return code.includes(VITE_ID_PREFIX)
+      ? code.replace(prefixedExternalRegex, (_, externalName) => externalName)
+      : // don't do anything when code does not contain the Vite prefix
+        code;
+  };
+}

packages/angular/build/src/tools/vite/plugins/id-prefix-plugin_spec.ts

@@ -6,34 +6,16 @@
  * found in the LICENSE file at https://angular.dev/license
  */
 
-import { createRemoveIdPrefixPlugin } from './id-prefix-plugin';
+import { createTransformer } from './id-prefix-plugin';
 
-/**
- * Runs the plugin's `configResolved` hook against a minimal fake resolved
- * configuration and returns the transform function of the plugin it registers.
- */
-function getTransform(externals: string[], base: string): (code: string) => string {
-  const plugin = createRemoveIdPrefixPlugin(externals);
-  const resolvedConfig = {
-    base,
-    plugins: [] as { name: string; transform?: (code: string) => string }[],
-  };
-
-  (plugin.configResolved as (config: unknown) => void)(resolvedConfig);
-
-  const pushedPlugin = resolvedConfig.plugins[0];
-  expect(pushedPlugin?.transform).toBeDefined();
-
-  // eslint-disable-next-line @typescript-eslint/no-non-null-assertion
-  return pushedPlugin.transform!;
-}
-
-describe('createRemoveIdPrefixPlugin', () => {
+describe('createTransformer', () => {
   it('should strip the prefix from every occurrence on a single (minified) line', () => {
-    const transform = getTransform(
-      ['@angular/common', '@angular/common/http', '@angular/core', '@angular/router'],
-      '/',
-    );
+    const transform = createTransformer('/', [
+      '@angular/common',
+      '@angular/common/http',
+      '@angular/core',
+      '@angular/router',
+    ]);
 
     const minified =
       'import{a}from"/@id/@angular/common/http";' +
@@ -48,23 +30,23 @@ describe('createRemoveIdPrefixPlugin', () => {
   });
 
   it('should strip the prefix from an external with a deep import path', () => {
-    const transform = getTransform(['@angular/common'], '/');
+    const transform = createTransformer('/', ['@angular/common']);
 
     expect(transform('import{h}from"/@id/@angular/common/http";')).toBe(
       'import{h}from"@angular/common/http";',
     );
   });
 
   it('should strip the prefix when a non-root base is configured', () => {
-    const transform = getTransform(['@angular/router'], '/app/');
+    const transform = createTransformer('/app/', ['@angular/router']);
 
     expect(transform('import{r}from"/app/@id/@angular/router";')).toBe(
       'import{r}from"@angular/router";',
     );
   });
 
   it('should strip the prefix from multi-line (unminified) code', () => {
-    const transform = getTransform(['@angular/common', '@angular/router'], '/');
+    const transform = createTransformer('/', ['@angular/common', '@angular/router']);
 
     const code =
       'import { CommonModule } from "/@id/@angular/common";\n' +
@@ -77,18 +59,9 @@ describe('createRemoveIdPrefixPlugin', () => {
   });
 
   it('should not modify imports that are not configured externals', () => {
-    const transform = getTransform(['@angular/router'], '/');
+    const transform = createTransformer('/', ['@angular/router']);
 
     const code = 'import{x}from"/@id/some-other-package";';
     expect(transform(code)).toBe(code);
   });
-
-  it('should not register a transform when there are no externals', () => {
-    const plugin = createRemoveIdPrefixPlugin([]);
-    const resolvedConfig = { base: '/', plugins: [] };
-
-    (plugin.configResolved as (config: unknown) => void)(resolvedConfig);
-
-    expect(resolvedConfig.plugins).toHaveSize(0);
-  });
 });