Add plugin support for occurrences (and fix typo)

pkg/analyzer_plugin/test/plugin/occurrences_mixin_test.dart

Index: pkg/analyzer_plugin/test/plugin/occurrences_mixin_test.dart
diff --git a/pkg/analyzer_plugin/test/plugin/occurrences_mixin_test.dart b/pkg/analyzer_plugin/test/plugin/occurrences_mixin_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..ea8a305cb540183cdb6ebc5b68a6bb5266ab8ef0
--- /dev/null
+++ b/pkg/analyzer_plugin/test/plugin/occurrences_mixin_test.dart
@@ -0,0 +1,127 @@
+// Copyright (c) 2017, 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 'dart:async';
+
+import 'package:analyzer/file_system/file_system.dart';
+import 'package:analyzer/file_system/memory_file_system.dart';
+import 'package:analyzer/src/dart/analysis/driver.dart';
+import 'package:analyzer_plugin/plugin/occurrences_mixin.dart';
+import 'package:analyzer_plugin/protocol/protocol.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart';
+import 'package:analyzer_plugin/protocol/protocol_generated.dart';
+import 'package:analyzer_plugin/src/utilities/occurrences/occurrences.dart';
+import 'package:analyzer_plugin/utilities/occurrences/occurrences.dart';
+import 'package:path/src/context.dart';
+import 'package:test/test.dart';
+import 'package:test_reflective_loader/test_reflective_loader.dart';
+
+import 'mocks.dart';
+
+void main() {
+  defineReflectiveTests(OccurrencesMixinTest);
+}
+
+@reflectiveTest
+class OccurrencesMixinTest {
+  MemoryResourceProvider resourceProvider = new MemoryResourceProvider();
+
+  String packagePath1;
+  String filePath1;
+  ContextRoot contextRoot1;
+
+  MockChannel channel;
+  _TestServerPlugin plugin;
+
+  void setUp() {
+    Context pathContext = resourceProvider.pathContext;
+
+    packagePath1 = resourceProvider.convertPath('/package1');
+    filePath1 = pathContext.join(packagePath1, 'lib', 'test.dart');
+    resourceProvider.newFile(filePath1, '');
+    contextRoot1 = new ContextRoot(packagePath1, <String>[]);
+
+    channel = new MockChannel();
+    plugin = new _TestServerPlugin(resourceProvider);
+    plugin.start(channel);
+  }
+
+  test_sendOccurrencesNotification() async {
+    await plugin.handleAnalysisSetContextRoots(
+        new AnalysisSetContextRootsParams([contextRoot1]));
+
+    Completer<Null> notificationReceived = new Completer<Null>();
+    channel.listen(null, onNotification: (Notification notification) {
+      expect(notification, isNotNull);
+      AnalysisOccurrencesParams params =
+          new AnalysisOccurrencesParams.fromNotification(notification);
+      expect(params.file, filePath1);
+      List<Occurrences> occurrenceList = params.occurrences;
+      expect(occurrenceList, hasLength(3));
+
+      void validate(String elementName, List<int> expectedOffsets) {
+        for (Occurrences occurrences in occurrenceList) {
+          if (occurrences.element.name == elementName) {
+            expect(occurrences.offsets, expectedOffsets);
+            expect(occurrences.length, elementName.length);
+            return;
+          }
+        }
+        fail('No occurence named $elementName');
+      }
+
+      validate('method', [10, 30]);
+      validate('C', [20, 40, 50, 60, 70]);
+      validate('local', [80]);
+      notificationReceived.complete();
+    });
+    await plugin.sendOccurrencesNotification(filePath1);
+    await notificationReceived.future;
+  }
+}
+
+class _TestOccurrencesContributor implements OccurrencesContributor {
+  Map<Element, List<int>> elements;
+
+  _TestOccurrencesContributor(this.elements);
+
+  @override
+  void computeOccurrences(
+      OccurrencesRequest request, OccurrencesCollector collector) {
+    elements.forEach((element, offsets) {
+      for (int offset in offsets) {
+        collector.addOccurrence(element, offset);
+      }
+    });
+  }
+}
+
+class _TestServerPlugin extends MockServerPlugin with OccurrencesMixin {
+  _TestServerPlugin(ResourceProvider resourceProvider)
+      : super(resourceProvider);
+
+  @override
+  List<OccurrencesContributor> getOccurrencesContributors(String path) {
+    Element element1 = new Element(ElementKind.METHOD, 'method', 0);
+    Element element2 = new Element(ElementKind.CLASS, 'C', 0);
+    Element element3 = new Element(ElementKind.LOCAL_VARIABLE, 'local', 0);
+    return <OccurrencesContributor>[
+      new _TestOccurrencesContributor({
+        element1: [10, 30],
+        element2: [20, 40, 60]
+      }),
+      new _TestOccurrencesContributor({
+        element2: [50, 70],
+        element3: [80]
+      })
+    ];
+  }
+
+  @override
+  Future<OccurrencesRequest> getOccurrencesRequest(String path) async {
+    AnalysisResult result = new AnalysisResult(
+        null, null, path, null, null, null, null, null, null, null, null);
+    return new DartOccurrencesRequestImpl(resourceProvider, result);
+  }
+}