first cut simple code completion results

pkg/analysis_server/test/completion_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.domain.completion;
+
+import 'dart:async';
+
+import 'package:analysis_server/src/constants.dart';
+import 'package:analysis_server/src/domain_completion.dart';
+import 'package:analysis_server/src/protocol.dart';
+import 'package:analysis_services/index/index.dart' show Index;
+import 'package:analysis_services/index/local_memory_index.dart';
+import 'package:analysis_testing/reflective_tests.dart';
+import 'package:unittest/unittest.dart';
+
+import 'analysis_abstract.dart';
+
+main() {
+  group('completion', () {
+    runReflectiveTests(CompletionTest);
+  });
+}
+
+@ReflectiveTestCase()
+class CompletionTest extends AbstractAnalysisTest {
+  String completionId;
+  List<CompletionSuggestion> suggestions = [];
+  bool suggestionsDone = false;
+
+  void assertHasResult(String completion) {
+    var cs = suggestions.firstWhere((cs) => cs.completion == completion, orElse: () {
+      var completions = suggestions.map((s) => s.completion).toList();
+      fail('expected "$completion" but found\n $completions');
+    });
+  }
+
+  void assertValidId(String id) {
+    expect(id, isNotNull);
+    expect(id.isNotEmpty, isTrue);
+  }
+
+  @override
+  Index createIndex() {
+    return createLocalMemoryIndex();
+  }
+
+  Future getSuggestions(String pattern, int offsetFromPatternStart) {
+    return waitForTasksFinished().then((_) {
+      int offset = testCode.indexOf(pattern) + offsetFromPatternStart;

[scheglov, 2014/07/17 21:09:32]

Would it be easier to use some special character, like ^ or ! as a marker for
the position to request completions? So, it'll be easier to write tests.

We could override addTestFile() in this class to find the completion offset and
remove the special character from the code.

[danrubel, 2014/07/17 21:38:45]

Great suggestion. https://codereview.chromium.org/402803004/

+      Request request = new Request('0', COMPLETION_GET_SUGGESTIONS);
+      request.setParameter(FILE, testFile);
+      request.setParameter(OFFSET, offset);
+      Response response = handleSuccessfulRequest(request);
+      completionId = response.getResult(ID);
+      assertValidId(completionId);
+      return waitForSuggestions();
+    });
+  }
+
+  void processNotification(Notification notification) {
+    if (notification.event == COMPLETION_RESULTS) {
+      String id = notification.getParameter(ID);
+      assertValidId(id);
+      if (id == completionId) {
+        expect(suggestionsDone, isFalse);
+        suggestionsDone = notification.getParameter(LAST);
+        expect(suggestionsDone, isNotNull);
+        for (Map<String, Object> json in notification.getParameter(RESULTS)) {
+          expect(json, isNotNull);
+          suggestions.add(new CompletionSuggestion.fromJson(json));
+        }
+      }
+    }
+  }
+
+  @override
+  void setUp() {
+    super.setUp();
+    createProject();
+    handler = new CompletionDomainHandler(server);
+  }
+
+  Future waitForSuggestions() {
+    if (suggestionsDone) {
+      return new Future.value();
+    }
+    return new Future.delayed(Duration.ZERO, waitForSuggestions);
+  }
+
+  test_suggestions() {
+    addTestFile('''
+      import 'dart:html';
+      main() {}
+    ''');
+    return getSuggestions('}', 0).then((_) {
+      assertHasResult('Object');
+      assertHasResult('HtmlElement');
+    });
+  }
+}