Add tests for recently added mixins and improve plugin tests

pkg/analyzer_plugin/test/plugin/navigation_mixin_test.dart

Index: pkg/analyzer_plugin/test/plugin/navigation_mixin_test.dart
diff --git a/pkg/analyzer_plugin/test/plugin/navigation_mixin_test.dart b/pkg/analyzer_plugin/test/plugin/navigation_mixin_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..295c76c87e158489f0446cdd77f13e8fbfd30e6e
--- /dev/null
+++ b/pkg/analyzer_plugin/test/plugin/navigation_mixin_test.dart
@@ -0,0 +1,96 @@
+// 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/dart/analysis/results.dart' hide AnalysisResult;
+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/navigation_mixin.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart';
+import 'package:analyzer_plugin/protocol/protocol_generated.dart';
+import 'package:analyzer_plugin/utilities/navigation/navigation.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(NavigationMixinTest);
+}
+
+@reflectiveTest
+class NavigationMixinTest {
+  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_handleAnalysisGetNavigation() async {
+    await plugin.handleAnalysisSetContextRoots(
+        new AnalysisSetContextRootsParams([contextRoot1]));
+
+    var result = await plugin.handleAnalysisGetNavigation(
+        new AnalysisGetNavigationParams(filePath1, 1, 2));
+    expect(result, isNotNull);
+    expect(result.files, hasLength(1));
+    expect(result.targets, hasLength(1));
+    expect(result.regions, hasLength(2));
+  }
+}
+
+class _TestNavigationContributor implements NavigationContributor {
+  int regionCount;
+
+  _TestNavigationContributor(this.regionCount);
+
+  @override
+  void computeNavigation(
+      NavigationRequest request, NavigationCollector collector) {
+    for (int i = 0; i < regionCount; i++) {
+      collector.addRegion(
+          i, 5, ElementKind.METHOD, new Location('a', 5, 5, 1, 5));
+    }
+  }
+}
+
+class _TestServerPlugin extends MockServerPlugin with NavigationMixin {
+  _TestServerPlugin(ResourceProvider resourceProvider)
+      : super(resourceProvider);
+
+  @override
+  List<NavigationContributor> getNavigationContributors(
+      AnalysisDriverGeneric driver) {
+    return <NavigationContributor>[
+      new _TestNavigationContributor(2),
+      new _TestNavigationContributor(1)
+    ];
+  }
+
+  @override
+  Future<ResolveResult> getResolveResultForNavigation(
+      AnalysisDriverGeneric driver, String path) async {
+    return new AnalysisResult(
+        null, null, null, null, null, null, null, null, null, null, null);
+  }
+}