fix(@angular-devkit/build-angular): improve package deep import Sass index resolution in esbuild plugin

When resolving Sass imports in the experimental esbuild-based browser application builder's Sass plugin,
previously imported modules are used as the base for resolution attempts to workaround the lack of the
importer file provided by Sass. When attempting to resolve a deep import into a package (including the
potential Sass index files), these previously imported modules also need to be checked. This is
particularly relevant when using the Yarn PnP or pnpm package managers which enforce strict dependency
resolution.

Fixes #24271

(cherry picked from commit 67752a4)

Author: clydin

packages/angular_devkit/build_angular/src/builders/browser-esbuild/sass-plugin.ts

@@ -31,6 +31,30 @@ export function createSassPlugin(options: { sourcemap: boolean; loadPaths?: stri
   return {
     name: 'angular-sass',
     setup(build: PluginBuild): void {
+      const resolveUrl = async (url: string, previousResolvedModules?: Set<string>) => {
+        let result = await build.resolve(url, {
+          kind: 'import-rule',
+          // This should ideally be the directory of the importer file from Sass
+          // but that is not currently available from the Sass importer API.
+          resolveDir: build.initialOptions.absWorkingDir,
+        });
+
+        // Workaround to support Yarn PnP without access to the importer file from Sass
+        if (!result.path && previousResolvedModules?.size) {
+          for (const previous of previousResolvedModules) {
+            result = await build.resolve(url, {
+              kind: 'import-rule',
+              resolveDir: previous,
+            });
+            if (result.path) {
+              break;
+            }
+          }
+        }
+
+        return result;
+      };
+
       build.onLoad({ filter: /\.s[ac]ss$/ }, async (args) => {
         // Lazily load Sass when a Sass file is found
         sassWorkerPool ??= new SassWorkerImplementation(true);
@@ -51,48 +75,30 @@ export function createSassPlugin(options: { sourcemap: boolean; loadPaths?: stri
                   url,
                   { previousResolvedModules }: FileImporterWithRequestContextOptions,
                 ): Promise<URL | null> => {
-                  let result = await build.resolve(url, {
-                    kind: 'import-rule',
-                    // This should ideally be the directory of the importer file from Sass
-                    // but that is not currently available from the Sass importer API.
-                    resolveDir: build.initialOptions.absWorkingDir,
-                  });
-
-                  // Workaround to support Yarn PnP without access to the importer file from Sass
-                  if (!result.path && previousResolvedModules?.size) {
-                    for (const previous of previousResolvedModules) {
-                      result = await build.resolve(url, {
-                        kind: 'import-rule',
-                        resolveDir: previous,
-                      });
-                    }
-                  }
+                  const result = await resolveUrl(url, previousResolvedModules);
 
                   // Check for package deep imports
                   if (!result.path) {
                     const parts = url.split('/');
-                    const hasScope = parts.length > 2 && parts[0].startsWith('@');
-                    if (hasScope || parts.length > 1) {
-                      const [nameOrScope, nameOrFirstPath, ...pathPart] = parts;
-                      const packageName = hasScope
-                        ? `${nameOrScope}/${nameOrFirstPath}`
-                        : nameOrScope;
-                      const packageResult = await build.resolve(packageName + '/package.json', {
-                        kind: 'import-rule',
-                        // This should ideally be the directory of the importer file from Sass
-                        // but that is not currently available from the Sass importer API.
-                        resolveDir: build.initialOptions.absWorkingDir,
-                      });
-
-                      if (packageResult.path) {
-                        return pathToFileURL(
-                          join(
-                            dirname(packageResult.path),
-                            !hasScope ? nameOrFirstPath : '',
-                            ...pathPart,
-                          ),
-                        );
-                      }
+                    const hasScope = parts.length >= 2 && parts[0].startsWith('@');
+                    const [nameOrScope, nameOrFirstPath, ...pathPart] = parts;
+                    const packageName = hasScope
+                      ? `${nameOrScope}/${nameOrFirstPath}`
+                      : nameOrScope;
+
+                    const packageResult = await resolveUrl(
+                      packageName + '/package.json',
+                      previousResolvedModules,
+                    );
+
+                    if (packageResult.path) {
+                      return pathToFileURL(
+                        join(
+                          dirname(packageResult.path),
+                          !hasScope ? nameOrFirstPath : '',
+                          ...pathPart,
+                        ),
+                      );
                     }
                   }