refactor(@angular/cli): improve error handling for package installation in ng add

This change enhances the error handling in the 'ng add' command's 'installPackageTask'. It now specifically catches 'PackageManagerError' exceptions and surfaces the standard output or standard error from the underlying package manager process. This provides users with more actionable information when a package installation fails.

Author: clydin

packages/angular/cli/src/commands/add/cli.ts

@@ -26,6 +26,7 @@ import {
 import {
   NgAddSaveDependency,
   PackageManager,
+  PackageManagerError,
   PackageManifest,
   PackageMetadata,
   createPackageManager,
@@ -565,36 +566,47 @@ export default class AddCommandModule
     // Only show if installation will actually occur
     task.title = 'Installing package';
 
-    if (context.savePackage === false) {
-      task.title += ' in temporary location';
-
-      // Temporary packages are located in a different directory
-      // Hence we need to resolve them using the temp path
-      const { workingDirectory } = await packageManager.acquireTempPackage(
-        packageIdentifier.toString(),
-        {
-          registry,
-        },
-      );
-
-      const tempRequire = createRequire(workingDirectory + '/');
-      assert(context.collectionName, 'Collection name should always be available');
-      const resolvedCollectionPath = tempRequire.resolve(
-        join(context.collectionName, 'package.json'),
-      );
+    try {
+      if (context.savePackage === false) {
+        task.title += ' in temporary location';
+
+        // Temporary packages are located in a different directory
+        // Hence we need to resolve them using the temp path
+        const { workingDirectory } = await packageManager.acquireTempPackage(
+          packageIdentifier.toString(),
+          {
+            registry,
+          },
+        );
+
+        const tempRequire = createRequire(workingDirectory + '/');
+        assert(context.collectionName, 'Collection name should always be available');
+        const resolvedCollectionPath = tempRequire.resolve(
+          join(context.collectionName, 'package.json'),
+        );
+
+        context.collectionName = dirname(resolvedCollectionPath);
+      } else {
+        await packageManager.add(
+          packageIdentifier.toString(),
+          'none',
+          savePackage !== 'dependencies',
+          false,
+          true,
+          {
+            registry,
+          },
+        );
+      }
+    } catch (e) {
+      if (e instanceof PackageManagerError) {
+        const output = e.stderr || e.stdout;
+        if (output) {
+          throw new CommandError(`Package installation failed: ${e.message}\nOutput: ${output}`);
+        }
+      }
 
-      context.collectionName = dirname(resolvedCollectionPath);
-    } else {
-      await packageManager.add(
-        packageIdentifier.toString(),
-        'none',
-        savePackage !== 'dependencies',
-        false,
-        true,
-        {
-          registry,
-        },
-      );
+      throw e;
     }
   }
 

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

@@ -9,5 +9,6 @@
 export { createPackageManager } from './factory';
 export type { PackageManagerName } from './package-manager-descriptor';
 export { PackageManager } from './package-manager';
+export { PackageManagerError } from './error';
 export type * from './package-metadata';
 export type { InstalledPackage } from './package-tree';