[flutter_tools] Adds tests of mdns analytics events (#41410)

packages/flutter_tools/test/general.shard/ios/devices_test.dart

@@ -23,6 +23,7 @@ import 'package:flutter_tools/src/ios/ios_workflow.dart';
 import 'package:flutter_tools/src/macos/xcode.dart';
 import 'package:flutter_tools/src/mdns_discovery.dart';
 import 'package:flutter_tools/src/project.dart';
+import 'package:flutter_tools/src/reporting/reporting.dart';
 import 'package:meta/meta.dart';
 import 'package:mockito/mockito.dart';
 import 'package:platform/platform.dart';
@@ -44,6 +45,7 @@ class MockMDnsObservatoryDiscovery extends Mock implements MDnsObservatoryDiscov
 class MockXcode extends Mock implements Xcode {}
 class MockFile extends Mock implements File {}
 class MockPortForwarder extends Mock implements DevicePortForwarder {}
+class MockUsage extends Mock implements Usage {}
 
 void main() {
   final FakePlatform macPlatform = FakePlatform.fromPlatform(const LocalPlatform());
@@ -84,6 +86,7 @@ void main() {
       MockPortForwarder mockPortForwarder;
       MockIMobileDevice mockIMobileDevice;
       MockIOSDeploy mockIosDeploy;
+      MockUsage mockUsage;
 
       Directory tempDir;
       Directory projectDir;
@@ -115,6 +118,7 @@ void main() {
         mockPortForwarder = MockPortForwarder();
         mockIMobileDevice = MockIMobileDevice();
         mockIosDeploy = MockIOSDeploy();
+        mockUsage = MockUsage();
 
         tempDir = fs.systemTempDirectory.createTempSync('flutter_tools_create_test.');
         projectDir = tempDir.childDirectory('flutter_project');
@@ -183,6 +187,7 @@ void main() {
           debuggingOptions: DebuggingOptions.enabled(const BuildInfo(BuildMode.debug, null)),
           platformArgs: <String, dynamic>{},
         );
+        verify(mockUsage.sendEvent('ios-mdns', 'success')).called(1);
         expect(launchResult.started, isTrue);
         expect(launchResult.hasObservatory, isTrue);
         expect(await device.stopApp(mockApp), isFalse);
@@ -193,6 +198,7 @@ void main() {
         MDnsObservatoryDiscovery: () => mockMDnsObservatoryDiscovery,
         Platform: () => macPlatform,
         ProcessManager: () => mockProcessManager,
+        Usage: () => mockUsage,
       });
 
       testUsingContext(' succeeds in debug mode when mDNS fails by falling back to manual protocol discovery', () async {
@@ -212,6 +218,7 @@ void main() {
           debuggingOptions: DebuggingOptions.enabled(const BuildInfo(BuildMode.debug, null)),
           platformArgs: <String, dynamic>{},
         );
+        verify(mockUsage.sendEvent('ios-mdns', 'failure')).called(1);
         expect(launchResult.started, isTrue);
         expect(launchResult.hasObservatory, isTrue);
         expect(await device.stopApp(mockApp), isFalse);
@@ -222,6 +229,7 @@ void main() {
         MDnsObservatoryDiscovery: () => mockMDnsObservatoryDiscovery,
         Platform: () => macPlatform,
         ProcessManager: () => mockProcessManager,
+        Usage: () => mockUsage,
       });
 
       testUsingContext(' fails in debug mode when mDNS fails and when Observatory URI is malformed', () async {