Make PlatformSelector use boolean_selector.

test/backend/platform_selector/evaluate_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:test/test.dart';
-import 'package:test/src/backend/operating_system.dart';
-import 'package:test/src/backend/platform_selector.dart';
-import 'package:test/src/backend/test_platform.dart';
-
-void main() {
-  test("new PlatformSelector.parse() disallows invalid variables", () {
-    expect(() => new PlatformSelector.parse("undefined"),
-        throwsFormatException);
-  });
-
-  group("operator:", () {
-    test("conditional", () {
-      _expectEval("vm ? vm : browser", true);
-      _expectEval("vm ? browser : vm", false);
-      _expectEval("browser ? vm : browser", false);
-      _expectEval("browser ? browser : vm", true);
-    });
-
-    test("or", () {
-      _expectEval("vm || vm", true);
-      _expectEval("vm || browser", true);
-      _expectEval("browser || vm", true);
-      _expectEval("browser || browser", false);
-    });
-
-    test("and", () {
-      _expectEval("vm && vm", true);
-      _expectEval("vm && browser", false);
-      _expectEval("browser && vm", false);
-      _expectEval("browser && browser", false);
-    });
-
-    test("not", () {
-      _expectEval("!vm", false);
-      _expectEval("!browser", true);
-    });
-  });
-
-  group("baseline variable:", () {
-    test("vm", () {
-      _expectEval("vm", true, platform: TestPlatform.vm);
-      _expectEval("vm", false, platform: TestPlatform.chrome);
-    });
-
-    test("chrome", () {
-      _expectEval("chrome", true, platform: TestPlatform.chrome);
-      _expectEval("chrome", false, platform: TestPlatform.vm);
-    });
-
-    test("windows", () {
-      _expectEval("windows", true, os: OperatingSystem.windows);
-      _expectEval("windows", false, os: OperatingSystem.linux);
-      _expectEval("windows", false, os: OperatingSystem.none);
-    });
-
-    test("mac-os", () {
-      _expectEval("mac-os", true, os: OperatingSystem.macOS);
-      _expectEval("mac-os", false, os: OperatingSystem.linux);
-      _expectEval("mac-os", false, os: OperatingSystem.none);
-    });
-
-    test("linux", () {
-      _expectEval("linux", true, os: OperatingSystem.linux);
-      _expectEval("linux", false, os: OperatingSystem.android);
-      _expectEval("linux", false, os: OperatingSystem.none);
-    });
-
-    test("android", () {
-      _expectEval("android", true, os: OperatingSystem.android);
-      _expectEval("android", false, os: OperatingSystem.linux);
-      _expectEval("android", false, os: OperatingSystem.none);
-    });
-  });
-
-  group("derived variable:", () {
-    test("dart-vm", () {
-      _expectEval("dart-vm", true, platform: TestPlatform.vm);
-      _expectEval("dart-vm", false, platform: TestPlatform.chrome);
-    });
-
-    test("browser", () {
-      _expectEval("browser", true, platform: TestPlatform.chrome);
-      _expectEval("browser", false, platform: TestPlatform.vm);
-    });
-
-    test("js", () {
-      _expectEval("js", true, platform: TestPlatform.chrome);
-      _expectEval("js", false, platform: TestPlatform.vm);
-    });
-
-    test("blink", () {
-      _expectEval("blink", true, platform: TestPlatform.chrome);
-      _expectEval("blink", false, platform: TestPlatform.vm);
-    });
-
-    test("posix", () {
-      _expectEval("posix", false, os: OperatingSystem.windows);
-      _expectEval("posix", true, os: OperatingSystem.macOS);
-      _expectEval("posix", true, os: OperatingSystem.linux);
-      _expectEval("posix", true, os: OperatingSystem.android);
-      _expectEval("posix", false, os: OperatingSystem.none);
-    });
-  });
-}
-
-/// Asserts that [expression] evaluates to [result] on [platform] and [os].
-///
-/// [platform] defaults to [TestPlatform.vm]; [os] defaults to the current
-/// operating system.
-void _expectEval(String expression, bool result, {TestPlatform platform,
-    OperatingSystem os}) {
-
-  var reason = 'Expected "$expression" to evaluate to $result';
-  if (platform != null && os != null) {
-    reason += ' on $platform and $os.';
-  } else if (platform != null || os != null) {
-    reason += ' on ${platform == null ? os : platform}';
-  }
-
-  expect(_eval(expression, platform: platform, os: os), equals(result),
-      reason: '$reason.');
-}
-
-/// Returns the result of evaluating [expression] on [platform] and [os].
-///
-/// [platform] defaults to [TestPlatform.vm]; [os] defaults to the current
-/// operating system.
-bool _eval(String expression, {TestPlatform platform, OperatingSystem os}) {
-  if (platform == null) platform = TestPlatform.vm;
-  if (os == null) os = OperatingSystem.findByIoName(Platform.operatingSystem);
-  var selector = new PlatformSelector.parse(expression);
-  return selector.evaluate(platform, os: os);
-}