feat(shorebird_cli): add Adb (#825)

packages/shorebird_cli/bin/shorebird.dart

@@ -1,6 +1,7 @@
 import 'dart:io';
 
 import 'package:scoped/scoped.dart';
+import 'package:shorebird_cli/src/android_sdk.dart';
 import 'package:shorebird_cli/src/android_studio.dart';
 import 'package:shorebird_cli/src/auth/auth.dart';
 import 'package:shorebird_cli/src/bundletool.dart';
@@ -17,6 +18,7 @@ Future<void> main(List<String> args) async {
     await runScoped(
       () async => ShorebirdCliCommandRunner().run(args),
       values: {
+        androidSdkRef,
         androidStudioRef,
         authRef,
         bundletoolRef,

packages/shorebird_cli/lib/src/adb.dart

@@ -0,0 +1,20 @@
+import 'package:shorebird_cli/src/android_sdk.dart';
+import 'package:shorebird_cli/src/process.dart';
+
+/// A wrapper around the `adb` command.
+class Adb {
+  Future<ShorebirdProcessResult> _exec(String command) async {
+    final adbPath = androidSdk.adbPath;
+    if (adbPath == null) throw Exception('Unable to locate adb.');
+
+    return process.run(adbPath, command.split(' '));
+  }
+
+  /// Starts the app with the given [package] name.
+  Future<void> startApp(String package) async {
+    final result = await _exec('shell monkey -p $package 1');
+    if (result.exitCode != 0) {
+      throw Exception('Unable to start app: ${result.stderr}');
+    }
+  }
+}

packages/shorebird_cli/lib/src/android_sdk.dart

@@ -2,12 +2,19 @@ import 'dart:io';
 
 import 'package:collection/collection.dart';
 import 'package:path/path.dart' as p;
+import 'package:scoped/scoped.dart';
 import 'package:shorebird_cli/src/platform.dart';
 
 // https://developer.android.com/studio/command-line/variables.html#envar
 const kAndroidHome = 'ANDROID_HOME';
 const kAndroidSdkRoot = 'ANDROID_SDK_ROOT';
 
+/// A reference to a [AndroidSdk] instance.
+final androidSdkRef = create(AndroidSdk.new);
+
+/// The [AndroidSdk] instance available in the current zone.
+AndroidSdk get androidSdk => read(androidSdkRef);
+
 /// A wrapper around Android SDK.
 class AndroidSdk {
   /// The path to the Android SDK installation.

packages/shorebird_cli/test/src/adb_test.dart

@@ -0,0 +1,96 @@
+import 'package:mocktail/mocktail.dart';
+import 'package:scoped/scoped.dart';
+import 'package:shorebird_cli/src/adb.dart';
+import 'package:shorebird_cli/src/android_sdk.dart';
+import 'package:shorebird_cli/src/process.dart';
+import 'package:test/test.dart';
+
+class _MockAndroidSdk extends Mock implements AndroidSdk {}
+
+class _MockShorebirdProcess extends Mock implements ShorebirdProcess {}
+
+void main() {
+  group(Adb, () {
+    const adbPath = '/path/to/adb';
+
+    late AndroidSdk androidSdk;
+    late ShorebirdProcess process;
+    late Adb adb;
+
+    R runWithOverrides<R>(R Function() body) {
+      return runScoped(
+        () => body(),
+        values: {
+          androidSdkRef.overrideWith(() => androidSdk),
+          processRef.overrideWith(() => process),
+        },
+      );
+    }
+
+    setUp(() {
+      androidSdk = _MockAndroidSdk();
+      process = _MockShorebirdProcess();
+      adb = Adb();
+
+      when(() => androidSdk.adbPath).thenReturn(adbPath);
+      when(
+        () => process.run(any(), any()),
+      ).thenAnswer(
+        (_) async => const ShorebirdProcessResult(
+          exitCode: 0,
+          stdout: '',
+          stderr: '',
+        ),
+      );
+    });
+
+    group('startApp', () {
+      const package = 'com.example.app';
+      test('throws when unable to locate adb', () async {
+        when(() => androidSdk.adbPath).thenReturn(null);
+        await expectLater(
+          () => runWithOverrides(() => adb.startApp(package)),
+          throwsA(
+            isA<Exception>().having(
+              (e) => e.toString(),
+              'exception()',
+              contains('Unable to locate adb'),
+            ),
+          ),
+        );
+      });
+
+      test('throws process exits with non-zero exit code', () async {
+        when(
+          () => process.run(any(), any()),
+        ).thenAnswer(
+          (_) async => const ShorebirdProcessResult(
+            exitCode: 1,
+            stdout: '',
+            stderr: 'oops',
+          ),
+        );
+        await expectLater(
+          () => runWithOverrides(() => adb.startApp(package)),
+          throwsA(
+            isA<Exception>().having(
+              (e) => e.toString(),
+              'exception()',
+              contains('Unable to start app: oops'),
+            ),
+          ),
+        );
+      });
+
+      test('completes when process exits with 0', () async {
+        await expectLater(
+          runWithOverrides(() => adb.startApp(package)),
+          completes,
+        );
+        verify(
+          () => process.run(adbPath, 'shell monkey -p $package 1'.split(' ')),
+        ).called(1);
+      });
+    });
+  });
+}