suggest "in" in for statement

pkg/analysis_server/test/services/completion/keyword_contributor_test.dart

 // Copyright (c) 2014, 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 test.services.completion.dart.keyword;
 
 import 'package:analysis_server/src/protocol.dart';
 import 'package:analysis_server/src/services/completion/dart_completion_manager.dart';
 import 'package:analysis_server/src/services/completion/keyword_contributor.dart';
 import 'package:analyzer/src/generated/scanner.dart';
@@ skipping 499 matching lines @@
     assertSuggestKeywords([Keyword.THIS]);
   }
 
   test_empty() {
     addTestSource('^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(DIRECTIVE_DECLARATION_AND_LIBRARY_KEYWORDS,
         relevance: DART_RELEVANCE_HIGH);
   }
 
+  test_for_expression_in() {

[Brian Wilkerson, 2015/08/10 13:56:18]

It would be good to have some negative tests here as well to ensure that we
don't suggest 'in' in a normal for loop, such as

for (int j = i^; j < length; j++) {}

[danrubel, 2015/08/10 14:42:25]

Good point. Added additional tests and handled new situation. Happy to address
any issues you find with the new code in a subsequent CL.

+    addTestSource('main() {for (int x i^)}');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords([Keyword.IN], relevance: DART_RELEVANCE_HIGH);
+  }
+
+  test_for_expression_in2() {

[Brian Wilkerson, 2015/08/10 13:56:18]

I'm not sure what the utility is of suggesting 'in' after the user types 'in'...

[danrubel, 2015/08/10 14:42:25]

It's good to ensure "in" is in the list of suggestions so that we don't
auto-insert something else when the user wanted "in".

+    addTestSource('main() {for (int x in^)}');
+    expect(computeFast(), isTrue);
+    assertSuggestKeywords([Keyword.IN], relevance: DART_RELEVANCE_HIGH);
+  }
+
   test_function_async() {
     addTestSource('main()^');
     expect(computeFast(), isTrue);
     assertSuggestKeywords(DECLARATION_KEYWORDS,
         pseudoKeywords: ['async'], relevance: DART_RELEVANCE_HIGH);
   }
 
   test_function_async2() {
     addTestSource('main()^{}');
     expect(computeFast(), isTrue);
@@ skipping 638 matching lines @@
         (c) => msg.writeln('  $c, ${other.contains(c) ? '' : '<<<<<<<<<<<'}'));
   }
 
   bool _equalSets(Iterable<String> iter1, Iterable<String> iter2) {
     if (iter1.length != iter2.length) return false;
     if (iter1.any((c) => !iter2.contains(c))) return false;
     if (iter2.any((c) => !iter1.contains(c))) return false;
     return true;
   }
 }