[flutter_tool] Fill in Fuchsia version string (#34516)

packages/flutter_tools/lib/src/fuchsia/fuchsia_device.dart

@@ -358,7 +358,20 @@ class FuchsiaDevice extends Device {
   Future<TargetPlatform> get targetPlatform async => TargetPlatform.fuchsia;
 
   @override
-  Future<String> get sdkNameAndVersion async => 'Fuchsia';
+  Future<String> get sdkNameAndVersion async {
+    const String versionPath = '/pkgfs/packages/build-info/0/data/version';
+    final RunResult catResult = await shell('cat $versionPath');
+    if (catResult.exitCode != 0) {
+      printTrace('Failed to cat $versionPath: ${catResult.stderr}');
+      return 'Fuchsia';
+    }
+    final String version = catResult.stdout.trim();
+    if (version.isEmpty) {
+      printTrace('$versionPath was empty');
+      return 'Fuchsia';
+    }
+    return 'Fuchsia $version';
+  }
 
   @override
   DeviceLogReader getLogReader({ApplicationPackage app}) =>

packages/flutter_tools/test/fuchsia/fuchsia_device_test.dart

@@ -571,6 +571,69 @@ void main() {
     });
 
   });
+
+  group('sdkNameAndVersion: ', () {
+    MockFile sshConfig;
+    MockProcessManager mockSuccessProcessManager;
+    MockProcessResult mockSuccessProcessResult;
+    MockProcessManager mockFailureProcessManager;
+    MockProcessResult mockFailureProcessResult;
+    MockProcessManager emptyStdoutProcessManager;
+    MockProcessResult emptyStdoutProcessResult;
+
+    setUp(() {
+      sshConfig = MockFile();
+      when(sshConfig.absolute).thenReturn(sshConfig);
+
+      mockSuccessProcessManager = MockProcessManager();
+      mockSuccessProcessResult = MockProcessResult();
+      when(mockSuccessProcessManager.run(any)).thenAnswer(
+          (Invocation invocation) => Future<ProcessResult>.value(mockSuccessProcessResult));
+      when(mockSuccessProcessResult.exitCode).thenReturn(0);
+      when<String>(mockSuccessProcessResult.stdout).thenReturn('version');
+      when<String>(mockSuccessProcessResult.stderr).thenReturn('');
+
+      mockFailureProcessManager = MockProcessManager();
+      mockFailureProcessResult = MockProcessResult();
+      when(mockFailureProcessManager.run(any)).thenAnswer(
+          (Invocation invocation) => Future<ProcessResult>.value(mockFailureProcessResult));
+      when(mockFailureProcessResult.exitCode).thenReturn(1);
+      when<String>(mockFailureProcessResult.stdout).thenReturn('');
+      when<String>(mockFailureProcessResult.stderr).thenReturn('');
+
+      emptyStdoutProcessManager = MockProcessManager();
+      emptyStdoutProcessResult = MockProcessResult();
+      when(emptyStdoutProcessManager.run(any)).thenAnswer((Invocation invocation) =>
+          Future<ProcessResult>.value(emptyStdoutProcessResult));
+      when(emptyStdoutProcessResult.exitCode).thenReturn(0);
+      when<String>(emptyStdoutProcessResult.stdout).thenReturn('');
+      when<String>(emptyStdoutProcessResult.stderr).thenReturn('');
+    });
+
+    testUsingContext('returns what we get from the device on success', () async {
+      final FuchsiaDevice device = FuchsiaDevice('123');
+      expect(await device.sdkNameAndVersion, equals('Fuchsia version'));
+    }, overrides: <Type, Generator>{
+      ProcessManager: () => mockSuccessProcessManager,
+      FuchsiaArtifacts: () => FuchsiaArtifacts(sshConfig: sshConfig),
+    });
+
+    testUsingContext('returns "Fuchsia" when device command fails', () async {
+      final FuchsiaDevice device = FuchsiaDevice('123');
+      expect(await device.sdkNameAndVersion, equals('Fuchsia'));
+    }, overrides: <Type, Generator>{
+      ProcessManager: () => mockFailureProcessManager,
+      FuchsiaArtifacts: () => FuchsiaArtifacts(sshConfig: sshConfig),
+    });
+
+    testUsingContext('returns "Fuchsia" when device gives an empty result', () async {
+      final FuchsiaDevice device = FuchsiaDevice('123');
+      expect(await device.sdkNameAndVersion, equals('Fuchsia'));
+    }, overrides: <Type, Generator>{
+      ProcessManager: () => emptyStdoutProcessManager,
+      FuchsiaArtifacts: () => FuchsiaArtifacts(sshConfig: sshConfig),
+    });
+  });
 }
 
 class FuchsiaModulePackage extends ApplicationPackage {