Add support for a global configuration file.

lib/src/executable.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.
 
 // TODO(nweiz): This is under lib so that it can be used by the unittest dummy
 // package. Once that package is no longer being updated, move this back into
 // bin.
 import 'dart:io';
 
+import 'package:path/path.dart' as p;
 import 'package:source_span/source_span.dart';
 import 'package:stack_trace/stack_trace.dart';
 import 'package:yaml/yaml.dart';
 
 import 'runner.dart';
 import 'runner/application_exception.dart';
 import 'runner/configuration.dart';
 import 'runner/version.dart';
 import 'util/exit_codes.dart' as exit_codes;
 import 'util/io.dart';
@@ skipping 32 matching lines @@
   if (transformers is! List) return false;
 
   return transformers.any((transformer) {
     if (transformer is String) return transformer == 'test/pub_serve';
     if (transformer is! Map) return false;
     if (transformer.keys.length != 1) return false;
     return transformer.keys.single == 'test/pub_serve';
   });
 }
 
+/// Returns the path to the global test configuration file.
+final String _globalConfigPath = (){
+  if (Platform.environment.containsKey('DART_TEST_CONFIG')) {
+    return Platform.environment['DART_TEST_CONFIG'];
+  } else if (Platform.operatingSystem == 'windows') {
+    return p.join(Platform.environment['LOCALAPPDATA'], 'DartTest.yaml');
+  } else {
+    return '${Platform.environment['HOME']}/.dart_test.yaml';
+  }
+}();
+
 main(List<String> args) async {
   var configuration;
   try {
     configuration = new Configuration.parse(args);
   } on FormatException catch (error) {
     _printUsage(error.message);
     exitCode = exit_codes.usage;
     return;
   }
 
   if (configuration.help) {
     _printUsage();
     return;
   }
 
   if (configuration.version) {
     var version = testVersion;
     if (version == null) {
       stderr.writeln("Couldn't find version number.");
       exitCode = exit_codes.data;
     } else {
       print(version);
     }
     return;
   }
 
   try {
+    var fileConfiguration = Configuration.empty;
+    if (new File(_globalConfigPath).existsSync()) {
+      fileConfiguration = fileConfiguration.merge(
+          new Configuration.load(_globalConfigPath, global: true));
+    }
+
     if (new File("dart_test.yaml").existsSync()) {
-      var fileConfiguration = new Configuration.load("dart_test.yaml");
-      configuration = fileConfiguration.merge(configuration);
+      fileConfiguration = fileConfiguration.merge(
+          new Configuration.load("dart_test.yaml"));
     }
+
+    configuration = fileConfiguration.merge(configuration);
   } on SourceSpanFormatException catch (error) {
     stderr.writeln(error.toString(color: configuration.color));
     exitCode = exit_codes.data;
     return;
   } on FormatException catch (error) {
     stderr.writeln(error.message);
     exitCode = exit_codes.data;
     return;
   } on IOException catch (error) {
     stderr.writeln(error.toString());
@@ skipping 77 matching lines @@
     output = stderr;
   }
 
   output.write("""${wordWrap(message)}
 
 Usage: pub run test [files or directories...]
 
 ${Configuration.usage}
 """);
 }