[dartdev] Provide no installation feedback in dart installed

Updates `dart installed` to provide feedback if nothing is installed. If they didn't specify `--all` but there are inactive tools, provide a suggestion to specify the `--all` flag as well.

Resolves https://github.com/dart-lang/sdk/issues/61626

Change-Id: I7d68fe91a29650c113047065e673e7a1139df847
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/510020
Reviewed-by: Daco Harkes <dacoharkes@google.com>
Reviewed-by: Ben Konyi <bkonyi@google.com>
Commit-Queue: Ben Konyi <bkonyi@google.com>

pkg/dartdev/lib/src/commands/installed.dart

@@ -12,6 +12,10 @@ import 'package:pub_formats/pub_formats.dart';
 class InstalledCommand extends DartdevCommand {
   static const cmdName = 'installed';
   static const cmdDescription = 'List globally installed Dart CLI tools.';
+  static const noToolsInstalledMessage = 'No Dart CLI tools installed.';
+  static const noActiveToolsInstalledMessage =
+      'No active Dart CLI tools installed. '
+      'Run "dart installed --all" to show inactive tools.';
 
   @override
   CommandCategory get commandCategory => CommandCategory.global;
@@ -34,11 +38,21 @@ on `PATH` are non-active.''',
     final all = argResults.flag('all');
 
     final installedPackages = getInstalledPackages();
-    for (final package in installedPackages) {
-      if (package.installed == Installed.not && !all) {
-        continue;
+    final packagesToShow = [
+      for (final package in installedPackages)
+        if (all || package.installed != Installed.not) package,
+    ];
+
+    if (packagesToShow.isEmpty) {
+      if (all || installedPackages.isEmpty) {
+        print(noToolsInstalledMessage);
+      } else {
+        print(noActiveToolsInstalledMessage);
+      }
+    } else {
+      for (final package in packagesToShow) {
+        print(package.toString());
       }
-      print(package.toString());
     }
 
     return 0;

pkg/dartdev/test/native_assets/install_test.dart

@@ -5,6 +5,7 @@
 import 'dart:convert';
 import 'dart:io';
 
+import 'package:dartdev/src/commands/installed.dart';
 import 'package:meta/meta.dart';
 import 'package:pub_formats/pub_formats.dart';
 import 'package:test/test.dart';
@@ -154,6 +155,67 @@ Run "dart help" to see global options.
     });
   }
 
+  skippableTest(
+    'dart installed with no installations',
+    timeout: longTimeout,
+    () async {
+      await inTempDir((tempUri) async {
+        final binDir = Directory.fromUri(tempUri.resolve('install/bin'));
+
+        final environment = {
+          _dartDirectoryEnvKey: tempUri.toFilePath(),
+          'PATH':
+              '${binDir.path}$_pathEnvVarSeparator'
+              '${Platform.environment['PATH']!}',
+        };
+
+        Future<RunProcessResult> runInstalled([
+          List<String> arguments = const [],
+        ]) => _runDartdev(
+          fromDartdevSource,
+          'installed',
+          arguments,
+          null,
+          environment,
+        );
+
+        final emptyResult = await runInstalled();
+        expect(
+          emptyResult.stdout.trim(),
+          equals(InstalledCommand.noToolsInstalledMessage),
+        );
+        expect(emptyResult.stderr, isEmpty);
+
+        final emptyAllResult = await runInstalled(['--all']);
+        expect(
+          emptyAllResult.stdout.trim(),
+          equals(InstalledCommand.noToolsInstalledMessage),
+        );
+        expect(emptyAllResult.stderr, isEmpty);
+
+        await _runDartdev(
+          fromDartdevSource,
+          'install',
+          [_package2Dir.path],
+          null,
+          environment,
+        );
+
+        // Delete the bin directory to inactivate the installed tool.
+        if (binDir.existsSync()) {
+          binDir.deleteSync(recursive: true);
+        }
+
+        final inactiveResult = await runInstalled();
+        expect(
+          inactiveResult.stdout.trim(),
+          equals(InstalledCommand.noActiveToolsInstalledMessage),
+        );
+        expect(inactiveResult.stderr, isEmpty);
+      });
+    },
+  );
+
   final argumentss = [
     (null, [_packageForTest]),
     (null, [_packageForTest, _packageVersion]),
@@ -735,7 +797,10 @@ void main(List<String> args) async {
           null,
           environment,
         );
-        expect(await runInstalled(), hasLength(0));
+        expect(
+          await runInstalled(),
+          equals([InstalledCommand.noToolsInstalledMessage]),
+        );
       });
     },
   );