refactor(@angular/cli): support project-root strategy for temporary packages in bun

This change introduces a 'project-root' strategy for acquiring temporary packages, which is now enabled for Bun. Bun has difficulty discovering and using configuration files (like '.npmrc') when executed in an isolated temporary directory.

With the 'project-root' strategy, 'bun add' is executed directly in the project's root directory using the '--no-save' flag. This ensures correct configuration inheritance and reliable package resolution. The cleanup for this strategy is currently a no-op to avoid potentially destructive deletions within the project's 'node_modules'.

Author: clydin

packages/angular/cli/src/package-managers/package-manager-descriptor.ts

@@ -65,6 +65,16 @@ export interface PackageManagerDescriptor {
   /** The flag to ignore peer dependency warnings/errors. */
   readonly ignorePeerDependenciesFlag?: string;
 
+  /**
+   * The strategy to use when acquiring a temporary package.
+   * - `temporary-directory`: The package is installed in a separate temporary directory. (Default)
+   * - `project-root`: The package is installed in the project root (e.g. `node_modules`), but not saved to `package.json`.
+   */
+  readonly tempPackageStrategy?: 'temporary-directory' | 'project-root';
+
+  /** The flag to install a package without saving it to `package.json`. Used with `project-root` strategy. */
+  readonly noSaveFlag?: string;
+
   /** A function that returns the arguments and environment variables to use a custom registry. */
   readonly getRegistryOptions?: (registry: string) => {
     args?: string[];
@@ -141,6 +151,7 @@ export const SUPPORTED_PACKAGE_MANAGERS = {
     saveExactFlag: '--save-exact',
     saveTildeFlag: '--save-tilde',
     saveDevFlag: '--save-dev',
+    noSaveFlag: '--no-save',
     noLockfileFlag: '--no-package-lock',
     ignoreScriptsFlag: '--ignore-scripts',
     ignorePeerDependenciesFlag: '--force',
@@ -242,6 +253,8 @@ export const SUPPORTED_PACKAGE_MANAGERS = {
     saveExactFlag: '--exact',
     saveTildeFlag: '', // Bun does not have a flag for tilde, it defaults to caret.
     saveDevFlag: '--development',
+    noSaveFlag: '--no-save',
+    tempPackageStrategy: 'project-root',
     noLockfileFlag: '', // Bun does not have a flag for this.
     ignoreScriptsFlag: '--ignore-scripts',
     getRegistryOptions: (registry: string) => ({ args: ['--registry', registry] }),

packages/angular/cli/src/package-managers/package-manager.ts

@@ -544,6 +544,18 @@ export class PackageManager {
     specifier: string,
     options: { registry?: string; ignoreScripts?: boolean } = {},
   ): Promise<{ workingDirectory: string; cleanup: () => Promise<void> }> {
+    if (this.descriptor.tempPackageStrategy === 'project-root') {
+      const flags = [
+        options.ignoreScripts ? this.descriptor.ignoreScriptsFlag : '',
+        this.descriptor.noSaveFlag,
+      ].filter((flag): flag is string => !!flag);
+      const args = [this.descriptor.addCommand, specifier, ...flags];
+
+      await this.#run(args, { ...options, cwd: this.cwd });
+
+      return { workingDirectory: this.cwd, cleanup: async () => {} };
+    }
+
     const workingDirectory = await this.host.createTempDirectory(this.options.tempDirectory);
     const cleanup = () => this.host.deleteDirectory(workingDirectory);