fix(@angular-devkit/schematics): support quiet package installs with Yarn 2+

Yarn 2 and higher no longer support the `--silent` flag.
The `NodePackageInstallTask` will now spawn package managers with the stdout ignored when quiet
mode is needed and only show stderr when the process exits unsuccessfully. This
provides the necessary functionality for the task without relying on package manager
options.

Author: clydin

packages/angular_devkit/schematics/tasks/package-manager/executor.ts

@@ -15,7 +15,6 @@ import { TaskExecutor, UnsuccessfulWorkflowExecution } from '../../src';
 import { NodePackageTaskFactoryOptions, NodePackageTaskOptions } from './options';
 
 interface PackageManagerProfile {
-  quietArgument?: string;
   commands: {
     installAll?: string;
     installPackage: string;
@@ -24,7 +23,6 @@ interface PackageManagerProfile {
 
 const packageManagers: { [name: string]: PackageManagerProfile } = {
   'npm': {
-    quietArgument: '--quiet',
     commands: {
       installAll: 'install',
       installPackage: 'install',
@@ -37,13 +35,11 @@ const packageManagers: { [name: string]: PackageManagerProfile } = {
     },
   },
   'yarn': {
-    quietArgument: '--silent',
     commands: {
       installPackage: 'add',
     },
   },
   'pnpm': {
-    quietArgument: '--silent',
     commands: {
       installAll: 'install',
       installPackage: 'install',
@@ -81,10 +77,15 @@ export default function (
 
     const bufferedOutput: { stream: NodeJS.WriteStream; data: Buffer }[] = [];
     const spawnOptions: SpawnOptions = {
-      stdio: options.hideOutput ? 'pipe' : 'inherit',
       shell: true,
       cwd: path.join(rootDirectory, options.workingDirectory || ''),
     };
+    if (options.hideOutput) {
+      spawnOptions.stdio = options.quiet ? ['ignore', 'ignore', 'pipe'] : 'pipe';
+    } else {
+      spawnOptions.stdio = options.quiet ? ['ignore', 'ignore', 'inherit'] : 'inherit';
+    }
+
     const args: string[] = [];
 
     if (options.packageName) {
@@ -96,10 +97,6 @@ export default function (
       args.push(taskPackageManagerProfile.commands.installAll);
     }
 
-    if (options.quiet && taskPackageManagerProfile.quietArgument) {
-      args.push(taskPackageManagerProfile.quietArgument);
-    }
-
     if (!options.allowScripts) {
       args.push('--ignore-scripts');
     }