Add a testOn parameter to test() and group().

test/runner/test_on_test.dart

 // Copyright (c) 2015, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 @TestOn("vm")
 
 import 'dart:io';
 
 import 'package:path/path.dart' as p;
 import 'package:unittest/src/util/io.dart';
 import 'package:unittest/unittest.dart';
 
 import '../io.dart';
 
 String _sandbox;
 
-final _vm = """
-@TestOn("vm")
-
-import 'package:unittest/unittest.dart';
-
-void main() {
-  test("success", () {});
-}
-""";
-
-final _chrome = """
-@TestOn("chrome")
-
-// Make sure that loading this test file on the VM will break.
-import 'dart:html';
-
-import 'package:unittest/unittest.dart';
-
-void main() {
-  test("success", () {});
-}
-""";
-
-final _thisOS = """
-@TestOn("$currentOS")
-
-import 'package:unittest/unittest.dart';
-
-void main() {
-  test("success", () {});
-}
-""";
-
-final _otherOS = """
-@TestOn("${Platform.isWindows ? "mac-os" : "windows"}")
-
-// Make sure that loading this test file on the VM will break.
-import 'dart:html';
-
-import 'package:unittest/unittest.dart';
-
-void main() {
-  test("success", () {});
-}
-""";
+final _otherOS = Platform.isWindows ? "mac-os" : "windows";
 
 void main() {
   setUp(() {
     _sandbox = Directory.systemTemp.createTempSync('unittest_').path;
   });
 
   tearDown(() {
     new Directory(_sandbox).deleteSync(recursive: true);
   });
 
-  test("runs a test suite on a matching platform", () {
-    new File(p.join(_sandbox, "vm_test.dart")).writeAsStringSync(_vm);
-
-    var result = _runUnittest(["vm_test.dart"]);
-    expect(result.stdout, contains("All tests passed!"));
-    expect(result.exitCode, equals(0));
-  });
-
-  test("doesn't run a test suite on a non-matching platform", () {
-    new File(p.join(_sandbox, "vm_test.dart")).writeAsStringSync(_vm);
-
-    var result = _runUnittest(["--platform", "chrome", "vm_test.dart"]);
-    expect(result.stdout, contains("No tests ran."));
-    expect(result.exitCode, equals(0));
-  });
-
-  test("runs a test suite on a matching operating system", () {
-    new File(p.join(_sandbox, "os_test.dart")).writeAsStringSync(_thisOS);
-
-    var result = _runUnittest(["os_test.dart"]);
-    expect(result.stdout, contains("All tests passed!"));
-    expect(result.exitCode, equals(0));
-  });
-
-  test("doesn't run a test suite on a non-matching operating system", () {
-    new File(p.join(_sandbox, "os_test.dart")).writeAsStringSync(_otherOS);
-
-    var result = _runUnittest(["os_test.dart"]);
-    expect(result.stdout, contains("No tests ran."));
-    expect(result.exitCode, equals(0));
-  });
-
-  test("only loads matching files when loading as a group", () {
-    new File(p.join(_sandbox, "vm_test.dart")).writeAsStringSync(_vm);
-    new File(p.join(_sandbox, "chrome_test.dart")).writeAsStringSync(_chrome);
-    new File(p.join(_sandbox, "this_os_test.dart")).writeAsStringSync(_thisOS);
-    new File(p.join(_sandbox, "other_os_test.dart"))
-        .writeAsStringSync(_otherOS);
-
-    var result = _runUnittest(["."]);
-    expect(result.stdout, contains("+2: All tests passed!"));
-    expect(result.exitCode, equals(0));
-  });
+  group("for suite", () {
+    test("runs a test suite on a matching platform", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a test suite on a non-matching platform", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "vm");
+
+      var result = _runUnittest(["--platform", "chrome", "vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("runs a test suite on a matching operating system", () {
+      _writeTestFile("os_test.dart", suiteTestOn: currentOS.name);
+
+      var result = _runUnittest(["os_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a test suite on a non-matching operating system", () {
+      _writeTestFile("os_test.dart", suiteTestOn: _otherOS,
+          loadable: false);
+
+      var result = _runUnittest(["os_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("only loads matching files when loading as a group", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "vm");
+      _writeTestFile("chrome_test.dart",
+          suiteTestOn: "chrome", loadable: false);
+      _writeTestFile("this_os_test.dart", suiteTestOn: currentOS.name);
+      _writeTestFile("other_os_test.dart",
+          suiteTestOn: _otherOS, loadable: false);
+
+      var result = _runUnittest(["."]);
+      expect(result.stdout, contains("+2: All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+  });
+
+  group("for group", () {
+    test("runs a VM group on the VM", () {
+      _writeTestFile("vm_test.dart", groupTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a Chrome group on the VM", () {
+      _writeTestFile("chrome_test.dart", groupTestOn: "chrome");
+
+      var result = _runUnittest(["chrome_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("runs a Chrome group on Chrome", () {
+      _writeTestFile("chrome_test.dart", groupTestOn: "chrome");
+
+      var result = _runUnittest(["--platform", "chrome", "chrome_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a VM group on Chrome", () {
+      _writeTestFile("vm_test.dart", groupTestOn: "vm");
+
+      var result = _runUnittest(["--platform", "chrome", "vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+  });
+
+  group("for test", () {
+    test("runs a VM test on the VM", () {
+      _writeTestFile("vm_test.dart", testTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a Chrome test on the VM", () {
+      _writeTestFile("chrome_test.dart", testTestOn: "chrome");
+
+      var result = _runUnittest(["chrome_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("runs a Chrome test on Chrome", () {
+      _writeTestFile("chrome_test.dart", testTestOn: "chrome");
+
+      var result = _runUnittest(["--platform", "chrome", "chrome_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't run a VM test on Chrome", () {
+      _writeTestFile("vm_test.dart", testTestOn: "vm");
+
+      var result = _runUnittest(["--platform", "chrome", "vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+  });
+
+  group("with suite, group, and test selectors", () {
+    test("runs the test if all selectors match", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "!browser",
+          groupTestOn: "!js", testTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("All tests passed!"));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't runs the test if the suite doesn't match", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "chrome",
+          groupTestOn: "!js", testTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't runs the test if the group doesn't match", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "!browser",
+          groupTestOn: "chrome", testTestOn: "vm");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+
+    test("doesn't runs the test if the test doesn't match", () {
+      _writeTestFile("vm_test.dart", suiteTestOn: "!browser",
+          groupTestOn: "!js", testTestOn: "chrome");
+
+      var result = _runUnittest(["vm_test.dart"]);
+      expect(result.stdout, contains("No tests ran."));
+      expect(result.exitCode, equals(0));
+    });
+  });
+}
+
+/// Writes a test file with some platform selectors to [filename].
+///
+/// Each of [suiteTestOn], [groupTestOn], and [testTestOn] is a platform
+/// selector that's suite-, group-, and test-level respectively. If [loadable]
+/// is `false`, the test file will be made unloadable on the Dart VM.
+void _writeTestFile(String filename, {String suiteTestOn, String groupTestOn,
+    String testTestOn, bool loadable: true}) {
+  var buffer = new StringBuffer();
+  if (suiteTestOn != null) buffer.writeln("@TestOn('$suiteTestOn')");
+  if (!loadable) buffer.writeln("import 'dart:html';");
+
+  buffer
+      ..writeln("import 'package:unittest/unittest.dart';")
+      ..writeln("void main() {")
+      ..writeln("  group('group', () {");
+
+  if (testTestOn != null) {
+    buffer.writeln("    test('test', () {}, testOn: '$testTestOn');");
+  } else {
+    buffer.writeln("    test('test', () {});");
+  }
+
+  if (groupTestOn != null) {
+    buffer.writeln("  }, testOn: '$groupTestOn');");
+  } else {
+    buffer.writeln("  });");
+  }
+
+  buffer.writeln("}");
+
+  new File(p.join(_sandbox, filename)).writeAsStringSync(buffer.toString());
 }
 
 ProcessResult _runUnittest(List<String> args) =>
     runUnittest(args, workingDirectory: _sandbox);