Add tests for recently added mixins and improve plugin tests

pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart

Index: pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart
diff --git a/pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart b/pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart
new file mode 100644
index 0000000000000000000000000000000000000000..ffd8b32a0b87babdf46cdb23fc65b9e1bdde8cb3
--- /dev/null
+++ b/pkg/analyzer_plugin/test/plugin/fix_mixin_test.dart
@@ -0,0 +1,104 @@
+// 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/error/error.dart';
+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/src/error/codes.dart';
+import 'package:analyzer/src/generated/source.dart';
+import 'package:analyzer_plugin/plugin/fix_mixin.dart';
+import 'package:analyzer_plugin/protocol/protocol_common.dart'
+    hide AnalysisError;
+import 'package:analyzer_plugin/protocol/protocol_generated.dart';
+import 'package:analyzer_plugin/utilities/fixes/fixes.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(FixesMixinTest);
+}
+
+@reflectiveTest
+class FixesMixinTest {
+  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_handleEditGetFixes() async {
+    await plugin.handleAnalysisSetContextRoots(
+        new AnalysisSetContextRootsParams([contextRoot1]));
+
+    EditGetFixesResult result =
+        await plugin.handleEditGetFixes(new EditGetFixesParams(filePath1, 13));
+    expect(result, isNotNull);
+    List<AnalysisErrorFixes> fixes = result.fixes;
+    expect(fixes, hasLength(1));
+    expect(fixes[0].fixes, hasLength(3));
+  }
+}
+
+class _TestFixContributor implements FixContributor {
+  List<PrioritizedSourceChange> changes;
+
+  _TestFixContributor(this.changes);
+
+  @override
+  void computeFixes(FixesRequest request, FixCollector collector) {
+    for (PrioritizedSourceChange change in changes) {
+      collector.addFix(request.error, change);
+    }
+  }
+}
+
+class _TestServerPlugin extends MockServerPlugin with FixesMixin {
+  _TestServerPlugin(ResourceProvider resourceProvider)
+      : super(resourceProvider);
+
+  PrioritizedSourceChange createChange() {
+    return new PrioritizedSourceChange(0, new SourceChange(''));
+  }
+
+  @override
+  List<FixContributor> getFixContributors(AnalysisDriverGeneric driver) {
+    return <FixContributor>[
+      new _TestFixContributor(<PrioritizedSourceChange>[createChange()]),
+      new _TestFixContributor(
+          <PrioritizedSourceChange>[createChange(), createChange()])
+    ];
+  }
+
+  @override
+  Future<ResolveResult> getResolveResultForFixes(
+      AnalysisDriverGeneric driver, String path) async {
+    AnalysisError error = new AnalysisError(
+        new MockSource(), 0, 0, CompileTimeErrorCode.AWAIT_IN_WRONG_CONTEXT);
+    return new AnalysisResult(null, null, null, null, null, null,
+        new LineInfo([0, 20]), null, null, [error], null);
+  }
+}