Add tests

tools/engine_tool/test/build_command_test.dart

@@ -360,11 +360,11 @@ void main() {
         '//flutter/fml:fml_arc_unittests',
       ]);
       expect(result, equals(0));
-      expect(testEnv.processHistory.length, greaterThan(6));
-      expect(testEnv.processHistory[6].command[0], contains('ninja'));
-      expect(testEnv.processHistory[6].command[2], endsWith('/host_debug'));
+      expect(testEnv.processHistory.length, greaterThan(7));
+      expect(testEnv.processHistory[7].command[0], contains('ninja'));
+      expect(testEnv.processHistory[7].command[2], endsWith('/host_debug'));
       expect(
-        testEnv.processHistory[6].command[5],
+        testEnv.processHistory[7].command[5],
         equals('flutter/fml:fml_arc_unittests'),
       );
     } finally {
@@ -389,21 +389,25 @@ void main() {
         '//flutter/...',
       ]);
       expect(result, equals(0));
-      expect(testEnv.processHistory.length, greaterThan(6));
-      expect(testEnv.processHistory[6].command[0], contains('ninja'));
-      expect(testEnv.processHistory[6].command[2], endsWith('/host_debug'));
+      expect(testEnv.processHistory.length, greaterThan(7));
+      expect(testEnv.processHistory[7].command[0], contains('ninja'));
+      expect(testEnv.processHistory[7].command[2], endsWith('/host_debug'));
       expect(
-        testEnv.processHistory[6].command[5],
+        testEnv.processHistory[7].command[5],
         equals('flutter/display_list:display_list_unittests'),
       );
       expect(
-        testEnv.processHistory[6].command[6],
+        testEnv.processHistory[7].command[6],
         equals('flutter/flow:flow_unittests'),
       );
       expect(
-        testEnv.processHistory[6].command[7],
+        testEnv.processHistory[7].command[7],
         equals('flutter/fml:fml_arc_unittests'),
       );
+      expect(
+        testEnv.processHistory[7].command[8],
+        equals('flutter/tools/engine_tool:build_command_test'),
+      );
     } finally {
       testEnv.cleanup();
     }

tools/engine_tool/test/fixtures.dart

@@ -316,6 +316,21 @@ String gnDescOutput() => '''
       "toolchain": "//build/toolchain/mac:clang_x64",
       "type": "executable",
       "visibility": [ "*" ]
-   }
+   },
+   "//flutter/tools/engine_tool:build_command_test": {
+       "args": [ "../../flutter/prebuilts/macos-x64/dart-sdk/bin/dart", "--deterministic", "compile", "exe", "--packages=/Users/chris/Developer/flutter/engine/src/flutter/tools/engine_tool/.dart_tool/package_config.json", "--output=/Users/chris/Developer/flutter/engine/src/out/host_debug/gen/flutter/tools/engine_tool/build_command_test", "/Users/chris/Developer/flutter/engine/src/flutter/tools/engine_tool/test/build_command_test.dart" ],
+       "deps": [  ],
+       "inputs": [ "//flutter/tools/engine_tool/test/build_command_test.dart", "//flutter/tools/engine_tool/.dart_tool/package_config.json" ],
+       "metadata": {
+          "action_type": [ "dart_executable" ]
+       },
+       "outputs": [ "//out/host_debug/gen/flutter/tools/engine_tool/build_command_test" ],
+       "public": "*",
+       "script": "//build/gn_run_binary.py",
+       "testonly": true,
+       "toolchain": "//build/toolchain/mac:clang_x64",
+       "type": "action",
+       "visibility": [ "*" ]
+    }
 }
 ''';

tools/engine_tool/test/gn_utils_test.dart

@@ -39,8 +39,18 @@ void main() {
   final List<CannedProcess> cannedProcesses = <CannedProcess>[
     CannedProcess((List<String> command) => command.contains('desc'),
         stdout: fixtures.gnDescOutput()),
-    CannedProcess((List<String> command) => command.contains('outputs'),
+    CannedProcess((List<String> command) =>
+        command.contains('outputs') && command.contains('//flutter/display_list:display_list_unittests'),
         stdout: 'display_list_unittests'),
+    CannedProcess((List<String> command) =>
+        command.contains('outputs') && command.contains('//flutter/flow:flow_unittests'),
+        stdout: 'flow_unittests'),
+    CannedProcess((List<String> command) =>
+        command.contains('outputs') && command.contains('//flutter/fml:fml_arc_unittests'),
+        stdout: 'fml_arc_unittests'),
+    CannedProcess((List<String> command) =>
+        command.contains('outputs') && command.contains('//flutter/tools/engine_tool:build_command_test'),
+        stdout: 'build_command_test'),
   ];
 
   test('find test targets', () async {
@@ -49,14 +59,19 @@ void main() {
     final Environment env = testEnvironment.environment;
     final Map<String, BuildTarget> testTargets =
         await findTargets(env, engine.outDir);
-    expect(testTargets.length, equals(3));
+    expect(testTargets.length, equals(4));
     expect(testTargets['//flutter/display_list:display_list_unittests'],
         notEquals(null));
     expect(
         testTargets['//flutter/display_list:display_list_unittests']!
             .executable!
             .path,
         endsWith('display_list_unittests'));
+    expect(
+        testTargets['//flutter/tools/engine_tool:build_command_test']!
+            .executable!
+            .path,
+        endsWith('build_command_test'));
   });
 
   test('process queue failure', () async {
@@ -65,7 +80,7 @@ void main() {
     final Environment env = testEnvironment.environment;
     final Map<String, BuildTarget> testTargets =
         await findTargets(env, engine.outDir);
-    expect(selectTargets(<String>['//...'], testTargets).length, equals(3));
+    expect(selectTargets(<String>['//...'], testTargets).length, equals(4));
     expect(
         selectTargets(<String>['//flutter/display_list'], testTargets).length,
         equals(0));

tools/engine_tool/test/query_command_test.dart

@@ -162,7 +162,7 @@ void main() {
       expect(result, equals(0));
       expect(
         env.logger.testLogs.length,
-        equals(4),
+        equals(5),
       );
       expect(env.logger.testLogs[1].message,
           startsWith('//flutter/display_list:display_list_unittests'));

tools/engine_tool/test/test_command_test.dart

@@ -42,11 +42,13 @@ void main() {
   final List<CannedProcess> cannedProcesses = <CannedProcess>[
     CannedProcess((List<String> command) => command.contains('desc'),
         stdout: fixtures.gnDescOutput()),
-    CannedProcess((List<String> command) => command.contains('outputs'),
+    CannedProcess((List<String> command) => command.contains('outputs') && command.contains('//flutter/display_list:display_list_unittests'),
         stdout: 'display_list_unittests'),
+    CannedProcess((List<String> command) => command.contains('outputs') && command.contains('//flutter/tools/engine_tool:build_command_test'),
+        stdout: 'build_command_test'),
   ];
 
-  test('test command executes test', () async {
+  test('test command executes executable test', () async {
     final TestEnvironment testEnvironment = TestEnvironment.withTestEngine(
       cannedProcesses: cannedProcesses,
     );
@@ -70,6 +72,30 @@ void main() {
     }
   });
 
+  test('test command executes dart_executable test', () async {
+    final TestEnvironment testEnvironment = TestEnvironment.withTestEngine(
+      cannedProcesses: cannedProcesses,
+    );
+    try {
+      final Environment env = testEnvironment.environment;
+      final ToolCommandRunner runner = ToolCommandRunner(
+        environment: env,
+        configs: configs,
+      );
+      final int result = await runner.run(<String>[
+        'test',
+        '//flutter/tools/engine_tool:build_command_test',
+      ]);
+      expect(result, equals(0));
+      expect(testEnvironment.processHistory.length, greaterThan(3));
+      final int offset = testEnvironment.processHistory.length - 1;
+      expect(testEnvironment.processHistory[offset].command[0],
+          endsWith('build_command_test'));
+    } finally {
+      testEnvironment.cleanup();
+    }
+  });
+
   test('test command skips non-testonly executables', () async {
     final TestEnvironment testEnvironment = TestEnvironment.withTestEngine(
       cannedProcesses: cannedProcesses,
@@ -85,7 +111,7 @@ void main() {
         '//third_party/protobuf:protoc',
       ]);
       expect(result, equals(1));
-      expect(testEnvironment.processHistory.length, lessThan(6));
+      expect(testEnvironment.processHistory.length, lessThan(7));
       expect(testEnvironment.processHistory.where((ExecutedProcess process) {
         return process.command[0].contains('protoc');
       }), isEmpty);