fix(@angular/cli): improve bun lockfile detection and optimize lockfile checks

This commit refactors the package manager lockfile detection logic to:
- Introduce a `LOCKFILE_NAMES` constant for better maintainability and clarity.
- Enhance Bun lockfile detection by checking for both `bun.lockb` and `bun.lock`.
- Optimize lockfile checks by reading the root directory files once and passing them to the `hasLockfile` method, reducing redundant file system operations.

This addresses issues where Bun lockfiles might not have been correctly identified.

closes #31128

Author: alan-agius4

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

@@ -8,13 +8,23 @@
 
 import { isJsonObject, json } from '@angular-devkit/core';
 import { execSync, spawn } from 'node:child_process';
-import { existsSync, promises as fs, realpathSync, rmSync } from 'node:fs';
+import { promises as fs, readdirSync, realpathSync, rmSync } from 'node:fs';
 import { tmpdir } from 'node:os';
 import { join } from 'node:path';
 import { PackageManager } from '../../lib/config/workspace-schema';
 import { AngularWorkspace, getProjectByCwd } from './config';
 import { memoize } from './memoize';
 
+/**
+ * A map of package managers to their corresponding lockfile names.
+ */
+const LOCKFILE_NAMES: Readonly<Record<PackageManager, string | readonly string[]>> = {
+  [PackageManager.Yarn]: 'yarn.lock',
+  [PackageManager.Pnpm]: 'pnpm-lock.yaml',
+  [PackageManager.Bun]: ['bun.lockb', 'bun.lock'],
+  [PackageManager.Npm]: 'package-lock.json',
+};
+
 interface PackageManagerOptions {
   saveDev: string;
   install: string;
@@ -29,7 +39,13 @@ export interface PackageManagerUtilsContext {
   root: string;
 }
 
+/**
+ * Utilities for interacting with various package managers.
+ */
 export class PackageManagerUtils {
+  /**
+   * @param context The context for the package manager utilities, including workspace and global configuration.
+   */
   constructor(private readonly context: PackageManagerUtilsContext) {}
 
   /** Get the package manager name. */
@@ -216,10 +232,12 @@ export class PackageManagerUtils {
       return packageManager;
     }
 
-    const hasNpmLock = this.hasLockfile(PackageManager.Npm);
-    const hasYarnLock = this.hasLockfile(PackageManager.Yarn);
-    const hasPnpmLock = this.hasLockfile(PackageManager.Pnpm);
-    const hasBunLock = this.hasLockfile(PackageManager.Bun);
+    const filesInRoot = readdirSync(this.context.root);
+
+    const hasNpmLock = this.hasLockfile(PackageManager.Npm, filesInRoot);
+    const hasYarnLock = this.hasLockfile(PackageManager.Yarn, filesInRoot);
+    const hasPnpmLock = this.hasLockfile(PackageManager.Pnpm, filesInRoot);
+    const hasBunLock = this.hasLockfile(PackageManager.Bun, filesInRoot);
 
     // PERF NOTE: `this.getVersion` spawns the package a the child_process which can take around ~300ms at times.
     // Therefore, we should only call this method when needed. IE: don't call `this.getVersion(PackageManager.Pnpm)` unless truly needed.
@@ -265,25 +283,18 @@ export class PackageManagerUtils {
     return PackageManager.Npm;
   }
 
-  private hasLockfile(packageManager: PackageManager): boolean {
-    let lockfileName: string;
-    switch (packageManager) {
-      case PackageManager.Yarn:
-        lockfileName = 'yarn.lock';
-        break;
-      case PackageManager.Pnpm:
-        lockfileName = 'pnpm-lock.yaml';
-        break;
-      case PackageManager.Bun:
-        lockfileName = 'bun.lockb';
-        break;
-      case PackageManager.Npm:
-      default:
-        lockfileName = 'package-lock.json';
-        break;
-    }
-
-    return existsSync(join(this.context.root, lockfileName));
+  /**
+   * Checks if a lockfile for a specific package manager exists in the root directory.
+   * @param packageManager The package manager to check for.
+   * @param filesInRoot An array of file names in the root directory.
+   * @returns True if the lockfile exists, false otherwise.
+   */
+  private hasLockfile(packageManager: PackageManager, filesInRoot: string[]): boolean {
+    const lockfiles = LOCKFILE_NAMES[packageManager];
+
+    return typeof lockfiles === 'string'
+      ? filesInRoot.includes(lockfiles)
+      : lockfiles.some((lockfile) => filesInRoot.includes(lockfile));
   }
 
   private getConfiguredPackageManager(): PackageManager | undefined {