Support tag configuration.

lib/test.dart

 // Copyright (c) 2013, 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.
 
 import 'dart:async';
 
 import 'package:path/path.dart' as p;
 
 import 'src/backend/declarer.dart';
 import 'src/backend/test_platform.dart';
@@ skipping 74 matching lines @@
 ///
 /// If [timeout] is passed, it's used to modify or replace the default timeout
 /// of 30 seconds. Timeout modifications take precedence in suite-group-test
 /// order, so [timeout] will also modify any timeouts set on the group or suite.
 ///
 /// If [skip] is a String or `true`, the test is skipped. If it's a String, it
 /// should explain why the test is skipped; this reason will be printed instead
 /// of running the test.
 ///
 /// If [tags] is passed, it declares user-defined tags that are applied to the
-/// test. These tags can be used to select or skip the test on the command line.
-/// It can be an [Iterable] of tag names, or a [String] representing a single
-/// tag.
+/// test. These tags can be used to select or skip the test on the command line,
+/// or to do bulk test configuration. All tags should be declared in the
+/// [package configuration file][configuring tags]. The parameter can be an
+/// [Iterable] of tag names, or a [String] representing a single tag.
+///
+/// [configuring tags]: https://github.com/dart-lang/test/blob/master/doc/package_config.md#configuring-tags
 ///
 /// [onPlatform] allows tests to be configured on a platform-by-platform
 /// basis. It's a map from strings that are parsed as [PlatformSelector]s to
 /// annotation classes: [Timeout], [Skip], or lists of those. These
 /// annotations apply only on the given platforms. For example:
 ///
 ///     test("potentially slow test", () {
 ///       // ...
 ///     }, onPlatform: {
 ///       // This test is especially slow on Windows.
@@ skipping 34 matching lines @@
 /// If [timeout] is passed, it's used to modify or replace the default timeout
 /// of 30 seconds. Timeout modifications take precedence in suite-group-test
 /// order, so [timeout] will also modify any timeouts set on the suite, and will
 /// be modified by any timeouts set on individual tests.
 ///
 /// If [skip] is a String or `true`, the group is skipped. If it's a String, it
 /// should explain why the group is skipped; this reason will be printed instead
 /// of running the group's tests.
 ///
 /// If [tags] is passed, it declares user-defined tags that are applied to the
-/// group. These tags can be used to select or skip the group's tests on the
-/// command line. It can be an [Iterable] of tag names, or a [String]
-/// representing a single tag.
+/// test. These tags can be used to select or skip the test on the command line,
+/// or to do bulk test configuration. All tags should be declared in the
+/// [package configuration file][configuring tags]. The parameter can be an
+/// [Iterable] of tag names, or a [String] representing a single tag.
+///
+/// [configuring tags]: https://github.com/dart-lang/test/blob/master/doc/package_config.md#configuring-tags
 ///
 /// [onPlatform] allows groups to be configured on a platform-by-platform
 /// basis. It's a map from strings that are parsed as [PlatformSelector]s to
 /// annotation classes: [Timeout], [Skip], or lists of those. These
 /// annotations apply only on the given platforms. For example:
 ///
 ///     group("potentially slow tests", () {
 ///       // ...
 ///     }, onPlatform: {
 ///       // These tests are especially slow on Windows.
@@ skipping 69 matching lines @@
 /// prefer [tearDown], and only use [tearDOwnAll] if the callback is
 /// prohibitively slow.
 void tearDownAll(callback()) => _declarer.tearDownAll(callback);
 
 /// Registers an exception that was caught for the current test.
 void registerException(error, [StackTrace stackTrace]) {
   // This will usually forward directly to [Invoker.current.handleError], but
   // going through the zone API allows other zones to consistently see errors.
   Zone.current.handleUncaughtError(error, stackTrace);
 }