Formatting constructor initializers a la the Style Guide.

pkg/analyzer_experimental/test/services/formatter_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 'package:unittest/unittest.dart';
 
 import 'package:analyzer_experimental/src/generated/scanner.dart';
 import 'package:analyzer_experimental/src/services/formatter_impl.dart';
 import 'package:analyzer_experimental/src/services/writer.dart';
 
@@ skipping 580 matching lines @@
     });
 
     test('CU - constructor initializers', () {
       expectCUFormatsTo(
           'class A {\n'
           '  int _a;\n'
           '  A(a) : _a = a;\n'
           '}\n',
           'class A {\n'
           '  int _a;\n'
-          '  A(a) : _a = a;\n'
+          '  A(a)\n'
+          '      : _a = a;\n'
           '}\n'
         );
     });
 
     test('CU - constructor auto field inits', () {
       expectCUFormatsTo(
           'class A {\n'
           '  int _a;\n'
           '  A(this._a);\n'
           '}\n',
           'class A {\n'
           '  int _a;\n'
           '  A(this._a);\n'
           '}\n'
         );
     });
 
     test('CU - parts', () {
       expectCUFormatsTo(
         'part of foo;',
         'part of foo;\n'
       );
     });
+    
+    test('CU (cons inits)', () {
+      expectCUFormatsTo('class X {\n'
+          '  var x, y;\n'
+          '  X() : x = 1, y = 2;\n'
+          '}\n', 
+          'class X {\n'
+          '  var x, y;\n'
+          '  X()\n'
+          '      : x = 1,\n' 
+          '        y = 2;\n'
+          '}\n'
+      );
+    });
 
     test('stmt', () {
       expectStmtFormatsTo(
          'if (true){\n'
          'if (true){\n'
          'if (true){\n'
          'return true;\n'
          '} else{\n'
          'return false;\n'
          '}\n'
@@ skipping 373 matching lines @@
 
 expectStreamsNotEqual(Token t1, Token t2) =>
     expect(() => new TokenStreamComparator(null, t1, t2).verifyEquals(),
     throwsA(new isInstanceOf<FormatterException>()));
 
 expectCUFormatsTo(src, expected) => 
     expect(formatCU(src).source, equals(expected));
 
 expectStmtFormatsTo(src, expected) => 
     expect(formatStatement(src), equals(expected));