Allow tests to be selected by name.

bin/unittest.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.
 
 library unittest.unittest;
 
 import 'dart:async';
 import 'dart:io';
 import 'dart:isolate';
 
 import 'package:args/args.dart';
 import 'package:stack_trace/stack_trace.dart';
 
 import 'package:unittest/src/backend/test_platform.dart';
 import 'package:unittest/src/runner/reporter/compact.dart';
 import 'package:unittest/src/runner/load_exception.dart';
 import 'package:unittest/src/runner/loader.dart';
 import 'package:unittest/src/util/exit_codes.dart' as exit_codes;
 import 'package:unittest/src/util/io.dart';
 import 'package:unittest/src/utils.dart';
 
 /// The argument parser used to parse the executable arguments.
 final _parser = new ArgParser(allowTrailingOptions: true);
 
 void main(List<String> args) {
   _parser.addFlag("help", abbr: "h", negatable: false,
       help: "Shows this usage information.");
   _parser.addOption("package-root", hide: true);
+  _parser.addOption("name",
+      abbr: 'n',
+      help: 'A substring of the name of the test to run.\n'
+          'Regular expression syntax is supported.');
+  _parser.addOption("plain-name",
+      abbr: 'N',
+      help: 'A plain-text substring of the name of the test to run.');
   _parser.addOption("platform",
       abbr: 'p',
       help: 'The platform(s) on which to run the tests.',
       allowed: TestPlatform.all.map((platform) => platform.identifier).toList(),
       defaultsTo: 'vm',
       allowMultiple: true);
   _parser.addFlag("color", defaultsTo: null,
       help: 'Whether to use terminal colors.\n(auto-detected by default)');
 
   var options;
@@ skipping 26 matching lines @@
       }
       paths = ["test"];
     }
 
     return Future.wait(paths.map((path) {
       if (new Directory(path).existsSync()) return loader.loadDir(path);
       if (new File(path).existsSync()) return loader.loadFile(path);
       throw new LoadException(path, 'Does not exist.');
     }));
   }).then((suites) {
+    suites = flatten(suites);
+
+    var pattern;
+    if (options["name"] != null) {
+      if (options["plain-name"] != null) {
+        _printUsage("--name and --plain-name may not both be passed.");
+        exitCode = exit_codes.data;
+        return null;
+      }
+      pattern = new RegExp(options["name"]);
+    } else if (options["plain-name"] != null) {
+      pattern = options["plain-name"];
+    }
+
+    if (pattern != null) {
+      suites = suites.map((suite) {
+        return suite.change(
+            tests: suite.tests.where((test) => test.name.contains(pattern)));
+      }).toList();
+
+      if (suites.every((suite) => suite.tests.isEmpty)) {
+        stderr.write('No tests match ');
+
+        if (pattern is RegExp) {
+          stderr.write('regular expression "${pattern.pattern}".');
+        } else {
+          stderr.writeln('"$pattern".');
+        }
+        exitCode = exit_codes.data;
+        return null;
+      }
+    }
+
     var reporter = new CompactReporter(flatten(suites), color: color);
     return reporter.run().then((success) {
       exitCode = success ? 0 : 1;
     }).whenComplete(() => reporter.close());
   }).catchError((error, stackTrace) {
     if (error is LoadException) {
       stderr.writeln(error.toString(color: color));
 
       // Only print stack traces for load errors that come from the user's 
       if (error.innerError is! IOException &&
@@ skipping 37 matching lines @@
     output = stderr;
   }
 
   output.write("""$message
 
 Usage: pub run unittest:unittest [files or directories...]
 
 ${_parser.usage}
 """);
 }