Make subclasses of AbstractContextTest asynchronous.

pkg/analysis_server/test/services/correction/fix_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.correction.fix;
 
 import 'dart:async';
 
 import 'package:analysis_server/plugin/edit/fix/fix_core.dart';
 import 'package:analysis_server/plugin/protocol/protocol.dart'
@@ skipping 34 matching lines @@
         error.errorCode != HintCode.UNUSED_LOCAL_VARIABLE;
   };
 
   String myPkgLibPath = '/packages/my_pkg/lib';
 
   Fix fix;
   SourceChange change;
   String resultCode;
 
   assert_undefinedFunction_create_returnType_bool(String lineWithTest) async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   bool b = true;
   $lineWithTest
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   bool b = true;
@@ skipping 125 matching lines @@
   }
 
   void _performAnalysis() {
     while (context.performAnalysisTask().hasMoreWork);
   }
 }
 
 @reflectiveTest
 class FixProcessorTest extends BaseFixProcessorTest {
   test_addFieldFormalParameters_hasRequiredParameter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class Test {
   final int a;
   final int b;
   final int c;
   Test(this.a);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_FIELD_FORMAL_PARAMETERS,
         '''
 class Test {
   final int a;
   final int b;
   final int c;
   Test(this.a, this.b, this.c);
 }
 ''');
   }
 
   test_addFieldFormalParameters_noParameters() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class Test {
   final int a;
   final int b;
   final int c;
   Test();
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_FIELD_FORMAL_PARAMETERS,
         '''
 class Test {
   final int a;
   final int b;
   final int c;
   Test(this.a, this.b, this.c);
 }
 ''');
   }
 
   test_addFieldFormalParameters_noRequiredParameter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class Test {
   final int a;
   final int b;
   final int c;
   Test([this.c]);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_FIELD_FORMAL_PARAMETERS,
         '''
 class Test {
   final int a;
   final int b;
   final int c;
   Test(this.a, this.b, [this.c]);
 }
 ''');
   }
 
   test_addMissingParameter_function_positional_hasNamed() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 test({int a}) {}
 main() {
   test(1);
 }
 ''');
     await assertNoFix(DartFixKind.ADD_MISSING_PARAMETER_POSITIONAL);
   }
 
   test_addMissingParameter_function_positional_hasZero() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 test() {}
 main() {
   test(1);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_POSITIONAL,
         '''
 test([int i]) {}
 main() {
   test(1);
 }
 ''');
   }
 
   test_addMissingParameter_function_required_hasNamed() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 test({int a}) {}
 main() {
   test(1);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_REQUIRED,
         '''
 test(int i, {int a}) {}
 main() {
   test(1);
 }
 ''');
   }
 
   test_addMissingParameter_function_required_hasOne() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 test(int a) {}
 main() {
   test(1, 2.0);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_REQUIRED,
         '''
 test(int a, double d) {}
 main() {
   test(1, 2.0);
 }
 ''');
   }
 
   test_addMissingParameter_function_required_hasZero() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 test() {}
 main() {
   test(1);
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_REQUIRED,
         '''
 test(int i) {}
 main() {
   test(1);
 }
 ''');
   }
 
   test_addMissingParameter_method_positional_hasOne() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   test(int a) {}
   main() {
     test(1, 2.0);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_POSITIONAL,
         '''
 class A {
   test(int a, [double d]) {}
   main() {
     test(1, 2.0);
   }
 }
 ''');
   }
 
   test_addMissingParameter_method_required_hasOne() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   test(int a) {}
   main() {
     test(1, 2.0);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_REQUIRED,
         '''
 class A {
   test(int a, double d) {}
   main() {
     test(1, 2.0);
   }
 }
 ''');
   }
 
   test_addMissingParameter_method_required_hasZero() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   test() {}
   main() {
     test(1);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_MISSING_PARAMETER_REQUIRED,
         '''
 class A {
   test(int i) {}
   main() {
     test(1);
   }
 }
 ''');
   }
 
   test_addPartOfDirective() async {
     String partCode = r'''
 // Comment first.
 // Comment second.
 
 class A {}
 ''';
     addSource('/part.dart', partCode);
-    resolveTestUnit('''
+    await resolveTestUnit('''
 library my.lib;
 part 'part.dart';
 ''');
     _performAnalysis();
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.ADD_PART_OF, error);
     change = fix.change;
     // apply to "file"
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/part.dart');
     expect(
         SourceEdit.applySequence(partCode, fileEdit.edits),
         r'''
 // Comment first.
 // Comment second.
 
 part of my.lib;
 
 class A {}
 ''');
   }
 
   test_addSync_asyncFor() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async';
 void main(Stream<String> names) {
   await for (String name in names) {
     print(name);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 import 'dart:async';
 Future main(Stream<String> names) async {
   await for (String name in names) {
     print(name);
   }
 }
 ''');
   }
 
   test_addSync_BAD_nullFunctionBody() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 var F = await;
 ''');
     await assertNoFix(DartFixKind.ADD_ASYNC);
   }
 
   test_addSync_blockFunctionBody() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo() {}
 main() {
   await foo();
 }
 ''');
     List<AnalysisError> errors = context.computeErrors(testSource);
     expect(errors, hasLength(2));
     errors.sort((a, b) => a.message.compareTo(b.message));
     // No fix for ";".
     {
@@ skipping 24 matching lines @@
   await foo();
 }
 ''');
     }
   }
 
   test_addSync_expressionFunctionBody() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER_AWAIT;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo() {}
 main() => await foo();
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 foo() {}
 main() async => await foo();
 ''');
   }
 
   test_addSync_returnFuture() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER_AWAIT;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo() {}
 int main() {
   await foo();
   return 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 import 'dart:async';
 
 foo() {}
 Future<int> main() async {
   await foo();
   return 42;
 }
 ''');
   }
 
   test_addSync_returnFuture_alreadyFuture() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER_AWAIT;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async';
 foo() {}
 Future<int> main() {
   await foo();
   return 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 import 'dart:async';
 foo() {}
 Future<int> main() async {
   await foo();
   return 42;
 }
 ''');
   }
 
   test_addSync_returnFuture_dynamic() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER_AWAIT;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo() {}
 dynamic main() {
   await foo();
   return 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 foo() {}
 dynamic main() async {
   await foo();
   return 42;
 }
 ''');
   }
 
   test_addSync_returnFuture_noType() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER_AWAIT;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo() {}
 main() {
   await foo();
   return 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_ASYNC,
         '''
 foo() {}
 main() async {
   await foo();
   return 42;
 }
 ''');
   }
 
   test_boolean() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   boolean v;
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_BOOLEAN_WITH_BOOL,
         '''
 main() {
   bool v;
 }
 ''');
   }
 
   test_canBeNullAfterNullAware_chain() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(x) {
   x?.a.b.c;
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_WITH_NULL_AWARE,
         '''
 main(x) {
   x?.a?.b?.c;
 }
 ''');
   }
 
   test_canBeNullAfterNullAware_methodInvocation() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(x) {
   x?.a.b();
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_WITH_NULL_AWARE,
         '''
 main(x) {
   x?.a?.b();
 }
 ''');
   }
 
   test_canBeNullAfterNullAware_propertyAccess() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(x) {
   x?.a().b;
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_WITH_NULL_AWARE,
         '''
 main(x) {
   x?.a()?.b;
 }
 ''');
   }
 
   test_changeToStaticAccess_method() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static foo() {}
 }
 main(A a) {
   a.foo();
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO_STATIC_ACCESS,
         '''
@@ skipping 15 matching lines @@
   static foo() {}
 }
 ''');
     addSource(
         '/libB.dart',
         r'''
 library libB;
 import 'libA.dart';
 class B extends A {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'libB.dart';
 main(B b) {
   b.foo();
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO_STATIC_ACCESS,
         '''
 import 'libA.dart';
 import 'libB.dart';
 main(B b) {
   A.foo();
 }
 ''');
   }
 
   test_changeToStaticAccess_method_prefixLibrary() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as pref;
 main(pref.Future f) {
   f.wait([]);
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO_STATIC_ACCESS,
         '''
 import 'dart:async' as pref;
 main(pref.Future f) {
   pref.Future.wait([]);
 }
 ''');
   }
 
   test_changeToStaticAccess_property() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static get foo => 42;
 }
 main(A a) {
   a.foo;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO_STATIC_ACCESS,
         '''
@@ skipping 15 matching lines @@
   static get foo => null;
 }
 ''');
     addSource(
         '/libB.dart',
         r'''
 library libB;
 import 'libA.dart';
 class B extends A {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'libB.dart';
 main(B b) {
   b.foo;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO_STATIC_ACCESS,
         '''
 import 'libA.dart';
 import 'libB.dart';
 main(B b) {
   A.foo;
 }
 ''');
   }
 
   test_changeTypeAnnotation_BAD_multipleVariables() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   String a, b = 42;
 }
 ''');
     await assertNoFix(DartFixKind.CHANGE_TYPE_ANNOTATION);
   }
 
   test_changeTypeAnnotation_BAD_notVariableDeclaration() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   String v;
   v = 42;
 }
 ''');
     await assertNoFix(DartFixKind.CHANGE_TYPE_ANNOTATION);
   }
 
   test_changeTypeAnnotation_OK_generic() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   String v = <int>[];
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TYPE_ANNOTATION,
         '''
 main() {
   List<int> v = <int>[];
 }
 ''');
   }
 
   test_changeTypeAnnotation_OK_simple() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   String v = 'abc'.length;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TYPE_ANNOTATION,
         '''
 main() {
   int v = 'abc'.length;
 }
 ''');
   }
 
   test_createClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test v = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CLASS,
         '''
 main() {
   Test v = null;
 }
 
 class Test {
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['Test v =', 'Test {']);
   }
 
   test_createClass_BAD_hasUnresolvedPrefix() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   prefix.Test v = null;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_CLASS);
   }
 
   test_createClass_inLibraryOfPrefix() async {
     String libCode = r'''
 library my.lib;
 
 class A {}
 ''';
     addSource('/lib.dart', libCode);
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'lib.dart' as lib;
 
 main() {
   lib.A a = null;
   lib.Test t = null;
 }
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_CLASS, error);
     change = fix.change;
     // apply to "lib.dart"
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/lib.dart');
     expect(
         SourceEdit.applySequence(libCode, fileEdit.edits),
         r'''
 library my.lib;
 
 class A {}
 
 class Test {
 }
 ''');
     expect(change.linkedEditGroups, isEmpty);
   }
 
   test_createClass_innerLocalFunction() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 f() {
   g() {
     Test v = null;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CLASS,
         '''
 f() {
   g() {
     Test v = null;
   }
 }
 
 class Test {
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['Test v =', 'Test {']);
   }
 
   test_createClass_itemOfList() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   var a = [Test];
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CLASS,
         '''
 main() {
   var a = [Test];
 }
 
 class Test {
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['Test];', 'Test {']);
   }
 
   test_createClass_itemOfList_inAnnotation() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class MyAnnotation {
   const MyAnnotation(a, b);
 }
 @MyAnnotation(int, const [Test])
 main() {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CLASS,
         '''
 class MyAnnotation {
   const MyAnnotation(a, b);
 }
 @MyAnnotation(int, const [Test])
 main() {}
 
 class Test {
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['Test])', 'Test {']);
   }
 
   test_createConstructor_forFinalFields() async {
     errorFilter = (AnalysisError error) {
       return error.message.contains("'a'");
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class Test {
   final int a;
   final int b = 2;
   final int c;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR_FOR_FINAL_FIELDS,
         '''
 class Test {
   final int a;
   final int b = 2;
   final int c;
 
   Test(this.a, this.c);
 }
 ''');
   }
 
   test_createConstructor_insteadOfSyntheticDefault() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int field;
 
   method() {}
 }
 main() {
   new A(1, 2.0);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR,
         '''
 class A {
   int field;
 
   A(int i, double d);
 
   method() {}
 }
 main() {
   new A(1, 2.0);
 }
 ''');
   }
 
   test_createConstructor_named() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   method() {}
 }
 main() {
   new A.named(1, 2.0);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR,
         '''
 class A {
   A.named(int i, double d);
 
   method() {}
 }
 main() {
   new A.named(1, 2.0);
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['named(int ', 'named(1']);
   }
 
   test_createConstructor_named_emptyClassBody() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {}
 main() {
   new A.named(1);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR,
         '''
 class A {
   A.named(int i);
 }
 main() {
   new A.named(1);
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['named(int ', 'named(1']);
   }
 
   test_createConstructorForFinalFields_inTopLevelMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   final int v;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_CONSTRUCTOR_FOR_FINAL_FIELDS);
   }
 
   test_createConstructorForFinalFields_topLevelField() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 final int v;
 ''');
     await assertNoFix(DartFixKind.CREATE_CONSTRUCTOR_FOR_FINAL_FIELDS);
   }
 
   test_createConstructorSuperExplicit() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A(bool p1, int p2, double p3, String p4, {p5});
 }
 class B extends A {
   B() {}
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_SUPER_CONSTRUCTOR_INVOCATION,
         '''
 class A {
   A(bool p1, int p2, double p3, String p4, {p5});
 }
 class B extends A {
   B() : super(false, 0, 0.0, '') {}
 }
 ''');
   }
 
   test_createConstructorSuperExplicit_hasInitializers() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A(int p);
 }
 class B extends A {
   int field;
   B() : field = 42 {}
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_SUPER_CONSTRUCTOR_INVOCATION,
         '''
 class A {
   A(int p);
 }
 class B extends A {
   int field;
   B() : field = 42, super(0) {}
 }
 ''');
   }
 
   test_createConstructorSuperExplicit_named() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A.named(int p);
 }
 class B extends A {
   B() {}
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_SUPER_CONSTRUCTOR_INVOCATION,
         '''
 class A {
   A.named(int p);
 }
 class B extends A {
   B() : super.named(0) {}
 }
 ''');
   }
 
   test_createConstructorSuperExplicit_named_private() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A._named(int p);
 }
 class B extends A {
   B() {}
 }
 ''');
     await assertNoFix(DartFixKind.ADD_SUPER_CONSTRUCTOR_INVOCATION);
   }
 
   test_createConstructorSuperExplicit_typeArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   A(T p);
 }
 class B extends A<int> {
   B();
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_SUPER_CONSTRUCTOR_INVOCATION,
         '''
 class A<T> {
   A(T p);
 }
 class B extends A<int> {
   B() : super(0);
 }
 ''');
   }
 
   test_createConstructorSuperImplicit() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A(p1, int p2, List<String> p3, [int p4]);
 }
 class B extends A {
   int existingField;
 
   void existingMethod() {}
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR_SUPER,
         '''
 class A {
   A(p1, int p2, List<String> p3, [int p4]);
 }
 class B extends A {
   int existingField;
 
   B(p1, int p2, List<String> p3) : super(p1, p2, p3);
 
   void existingMethod() {}
 }
 ''');
   }
 
   test_createConstructorSuperImplicit_fieldInitializer() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int _field;
   A(this._field);
 }
 class B extends A {
   int existingField;
 
   void existingMethod() {}
 }
 ''');
@@ skipping 23 matching lines @@
 ''');
     addSource(
         '/libB.dart',
         r'''
 library libB;
 import 'libA.dart';
 class B {
   B(A a);
 }
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'libB.dart';
 class C extends B {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR_SUPER,
         '''
 import 'libA.dart';
 import 'libB.dart';
 class C extends B {
   C(A a) : super(a);
 }
 ''');
   }
 
   test_createConstructorSuperImplicit_named() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A.named(p1, int p2);
 }
 class B extends A {
   int existingField;
 
   void existingMethod() {}
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR_SUPER,
         '''
 class A {
   A.named(p1, int p2);
 }
 class B extends A {
   int existingField;
 
   B.named(p1, int p2) : super.named(p1, p2);
 
   void existingMethod() {}
 }
 ''');
   }
 
   test_createConstructorSuperImplicit_private() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A._named(p);
 }
 class B extends A {
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_CONSTRUCTOR_SUPER);
   }
 
   test_createConstructorSuperImplicit_typeArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class C<T> {
   final T x;
   C(this.x);
 }
 class D extends C<int> {
 }''');
     await assertHasFix(
         DartFixKind.CREATE_CONSTRUCTOR_SUPER,
         '''
 class C<T> {
   final T x;
   C(this.x);
 }
 class D extends C<int> {
   D(int x) : super(x);
 }''');
   }
 
   test_createField_BAD_inEnum() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 enum MyEnum {
   AAA, BBB
 }
 main() {
   MyEnum.foo;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_FIELD);
   }
 
   test_createField_BAD_inSDK() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(List p) {
   p.foo = 1;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_FIELD);
   }
 
   test_createField_getter_multiLevel() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 class B {
   A a;
 }
 class C {
   B b;
 }
 main(C c) {
   int v = c.b.a.test;
@@ skipping 11 matching lines @@
 class C {
   B b;
 }
 main(C c) {
   int v = c.b.a.test;
 }
 ''');
   }
 
   test_createField_getter_qualified_instance() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   int v = a.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 }
 main(A a) {
   int v = a.test;
 }
 ''');
   }
 
   test_createField_getter_qualified_instance_dynamicType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   B b;
   void f(Object p) {
     p == b.test;
   }
 }
 class B {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   B b;
   void f(Object p) {
     p == b.test;
   }
 }
 class B {
   var test;
 }
 ''');
   }
 
   test_createField_getter_qualified_propagatedType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A get self => this;
 }
 main() {
   var a = new A();
   int v = a.self.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 
   A get self => this;
 }
 main() {
   var a = new A();
   int v = a.self.test;
 }
 ''');
   }
 
   test_createField_getter_unqualified_instance_asInvocationArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     f(test);
   }
 }
 f(String s) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   String test;
 
   main() {
     f(test);
   }
 }
 f(String s) {}
 ''');
   }
 
   test_createField_getter_unqualified_instance_assignmentRhs() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     int v = test;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 
   main() {
     int v = test;
   }
 }
 ''');
   }
 
   test_createField_getter_unqualified_instance_asStatement() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     test;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   var test;
 
   main() {
     test;
   }
 }
 ''');
   }
 
   test_createField_hint() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   var x = a;
   int v = x.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 }
 main(A a) {
   var x = a;
   int v = x.test;
 }
 ''');
   }
 
   test_createField_hint_setter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   var x = a;
   x.test = 0;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
@@ skipping 14 matching lines @@
 library libA;
 class A {}
 ''');
     addSource(
         '/libB.dart',
         r'''
 library libB;
 import 'libA.dart';
 A getA() => null;
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'libB.dart';
 class C {
 }
 main(C c) {
   c.test = getA();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 import 'libA.dart';
 import 'libB.dart';
 class C {
   A test;
 }
 main(C c) {
   c.test = getA();
 }
 ''');
   }
 
   test_createField_setter_generic_BAD() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 class B<T> {
   List<T> items;
   main(A a) {
     a.test = items;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   List test;
 }
 class B<T> {
   List<T> items;
   main(A a) {
     a.test = items;
   }
 }
 ''');
   }
 
   test_createField_setter_generic_OK_local() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   List<T> items;
 
   main(A a) {
     test = items;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A<T> {
   List<T> items;
 
   List<T> test;
 
   main(A a) {
     test = items;
   }
 }
 ''');
   }
 
   test_createField_setter_qualified_instance_hasField() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int aaa;
   int zzz;
 
   existingMethod() {}
 }
 main(A a) {
   a.test = 5;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int aaa;
   int zzz;
 
   int test;
 
   existingMethod() {}
 }
 main(A a) {
   a.test = 5;
 }
 ''');
   }
 
   test_createField_setter_qualified_instance_hasMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   existingMethod() {}
 }
 main(A a) {
   a.test = 5;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 
   existingMethod() {}
 }
 main(A a) {
   a.test = 5;
 }
 ''');
   }
 
   test_createField_setter_qualified_static() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main() {
   A.test = 5;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   static int test;
 }
 main() {
   A.test = 5;
 }
 ''');
   }
 
   test_createField_setter_unqualified_instance() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     test = 5;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   int test;
 
   main() {
     test = 5;
   }
 }
 ''');
   }
 
   test_createField_setter_unqualified_static() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static main() {
     test = 5;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FIELD,
         '''
 class A {
   static int test;
 
   static main() {
     test = 5;
   }
 }
 ''');
   }
 
   test_createFile_forImport() async {
     testFile = '/my/project/bin/test.dart';
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'my_file.dart';
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_FILE, error);
     change = fix.change;
     // validate change
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/my/project/bin/my_file.dart');
     expect(fileEdit.fileStamp, -1);
     expect(fileEdit.edits, hasLength(1));
     expect(fileEdit.edits[0].replacement, contains('library my_file;'));
   }
 
   test_createFile_forImport_BAD_inPackage_lib_justLib() async {
     provider.newFile('/projects/my_package/pubspec.yaml', 'name: my_package');
     testFile = '/projects/my_package/test.dart';
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'lib';
 ''');
     await assertNoFix(DartFixKind.CREATE_FILE);
   }
 
   test_createFile_forImport_BAD_notDart() async {
     testFile = '/my/project/bin/test.dart';
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'my_file.txt';
 ''');
     await assertNoFix(DartFixKind.CREATE_FILE);
   }
 
   test_createFile_forImport_inPackage_lib() async {
     provider.newFile('/projects/my_package/pubspec.yaml', 'name: my_package');
     testFile = '/projects/my_package/lib/test.dart';
     provider.newFolder('/projects/my_package/lib');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'a/bb/c_cc/my_lib.dart';
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_FILE, error);
     change = fix.change;
     // validate change
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/projects/my_package/lib/a/bb/c_cc/my_lib.dart');
     expect(fileEdit.fileStamp, -1);
     expect(fileEdit.edits, hasLength(1));
     expect(fileEdit.edits[0].replacement,
         contains('library my_package.a.bb.c_cc.my_lib;'));
   }
 
   test_createFile_forImport_inPackage_test() async {
     provider.newFile('/projects/my_package/pubspec.yaml', 'name: my_package');
     testFile = '/projects/my_package/test/misc/test_all.dart';
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'a/bb/my_lib.dart';
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_FILE, error);
     change = fix.change;
     // validate change
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/projects/my_package/test/misc/a/bb/my_lib.dart');
     expect(fileEdit.fileStamp, -1);
     expect(fileEdit.edits, hasLength(1));
     expect(fileEdit.edits[0].replacement,
         contains('library my_package.test.misc.a.bb.my_lib;'));
   }
 
   test_createFile_forPart() async {
     testFile = '/my/project/bin/test.dart';
-    resolveTestUnit('''
+    await resolveTestUnit('''
 library my.lib;
 part 'my_part.dart';
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_FILE, error);
     change = fix.change;
     // validate change
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
@@ skipping 16 matching lines @@
 part 'my_part.dart';
 ''',
         Uri.parse('package:my/test.dart'));
     // configure SourceFactory
     UriResolver pkgResolver = new PackageMapUriResolver(provider, {
       'my': <Folder>[provider.getResource('/my/lib')],
     });
     context.sourceFactory = new SourceFactory(
         [AbstractContextTest.SDK_RESOLVER, pkgResolver, resourceResolver]);
     // prepare fix
-    testUnit = resolveLibraryUnit(testSource);
+    testUnit = await resolveLibraryUnit(testSource);
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_FILE, error);
     change = fix.change;
     // validate change
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/my/lib/my_part.dart');
     expect(fileEdit.fileStamp, -1);
     expect(fileEdit.edits, hasLength(1));
     expect(fileEdit.edits[0].replacement, contains('part of my.lib;'));
   }
 
   test_createGetter_BAD_inSDK() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(List p) {
   int v = p.foo;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_GETTER);
   }
 
   test_createGetter_hint_getter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   var x = a;
   int v = x.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   int get test => null;
 }
 main(A a) {
   var x = a;
   int v = x.test;
 }
 ''');
   }
 
   test_createGetter_location_afterLastGetter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int existingField;
 
   int get existingGetter => null;
 
   existingMethod() {}
 }
 main(A a) {
   int v = a.test;
 }
@@ skipping 10 matching lines @@
 
   existingMethod() {}
 }
 main(A a) {
   int v = a.test;
 }
 ''');
   }
 
   test_createGetter_multiLevel() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 class B {
   A a;
 }
 class C {
   B b;
 }
 main(C c) {
   int v = c.b.a.test;
@@ skipping 11 matching lines @@
 class C {
   B b;
 }
 main(C c) {
   int v = c.b.a.test;
 }
 ''');
   }
 
   test_createGetter_qualified_instance() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   int v = a.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   int get test => null;
 }
 main(A a) {
   int v = a.test;
 }
 ''');
   }
 
   test_createGetter_qualified_instance_dynamicType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   B b;
   void f(Object p) {
     p == b.test;
   }
 }
 class B {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   B b;
   void f(Object p) {
     p == b.test;
   }
 }
 class B {
   get test => null;
 }
 ''');
   }
 
   test_createGetter_qualified_propagatedType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   A get self => this;
 }
 main() {
   var a = new A();
   int v = a.self.test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   A get self => this;
 
   int get test => null;
 }
 main() {
   var a = new A();
   int v = a.self.test;
 }
 ''');
   }
 
   test_createGetter_setterContext() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   a.test = 42;
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_GETTER);
   }
 
   test_createGetter_unqualified_instance_asInvocationArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     f(test);
   }
 }
 f(String s) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   String get test => null;
 
   main() {
     f(test);
   }
 }
 f(String s) {}
 ''');
   }
 
   test_createGetter_unqualified_instance_assignmentLhs() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     test = 42;
   }
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_GETTER);
   }
 
   test_createGetter_unqualified_instance_assignmentRhs() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     int v = test;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   int get test => null;
 
   main() {
     int v = test;
   }
 }
 ''');
   }
 
   test_createGetter_unqualified_instance_asStatement() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     test;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_GETTER,
         '''
 class A {
   get test => null;
 
   main() {
     test;
   }
 }
 ''');
   }
 
   test_createLocalVariable_functionType_named() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 typedef MY_FUNCTION(int p);
 foo(MY_FUNCTION f) {}
 main() {
   foo(bar);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 typedef MY_FUNCTION(int p);
 foo(MY_FUNCTION f) {}
 main() {
   MY_FUNCTION bar;
   foo(bar);
 }
 ''');
   }
 
   test_createLocalVariable_functionType_synthetic() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo(f(int p)) {}
 main() {
   foo(bar);
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_LOCAL_VARIABLE);
   }
 
   test_createLocalVariable_read_typeAssignment() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   int a = test;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   int test;
   int a = test;
 }
 ''');
   }
 
   test_createLocalVariable_read_typeCondition() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   if (!test) {
     print(42);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   bool test;
   if (!test) {
     print(42);
   }
 }
 ''');
   }
 
   test_createLocalVariable_read_typeInvocationArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   f(test);
 }
 f(String p) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   String test;
   f(test);
 }
 f(String p) {}
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['String test;']);
     _assertLinkedGroup(change.linkedEditGroups[1], ['test;', 'test);']);
   }
 
   test_createLocalVariable_read_typeInvocationTarget() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   test.add('hello');
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   var test;
   test.add('hello');
 }
 ''');
     _assertLinkedGroup(change.linkedEditGroups[0], ['test;', 'test.add(']);
   }
 
   test_createLocalVariable_write_assignment() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   test = 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   var test = 42;
 }
 ''');
   }
 
   test_createLocalVariable_write_assignment_compound() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   test += 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_LOCAL_VARIABLE,
         '''
 main() {
   int test;
   test += 42;
 }
 ''');
   }
 
   test_createMissingMethodCall() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class C implements Function {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_METHOD_CALL,
         '''
 class C implements Function {
   call() {
     // TODO: implement call
   }
 }
 ''');
   }
 
   test_createMissingOverrides_field_untyped() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   var f;
 }
 
 class B implements A {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 class A {
   var f;
 }
 
 class B implements A {
   @override
   var f;
 }
 ''');
   }
 
   test_createMissingOverrides_functionTypeAlias() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 typedef int Binary(int left, int right);
 
 abstract class Emulator {
   void performBinary(Binary binary);
 }
 
 class MyEmulator extends Emulator {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 typedef int Binary(int left, int right);
 
 abstract class Emulator {
   void performBinary(Binary binary);
 }
 
 class MyEmulator extends Emulator {
   @override
   void performBinary(Binary binary) {
     // TODO: implement performBinary
   }
 }
 ''');
   }
 
   test_createMissingOverrides_functionTypedParameter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   forEach(int f(double p1, String p2));
 }
 
 class B extends A {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 abstract class A {
   forEach(int f(double p1, String p2));
 }
 
 class B extends A {
   @override
   forEach(int f(double p1, String p2)) {
     // TODO: implement forEach
   }
 }
 ''');
   }
 
   test_createMissingOverrides_generics_typeArguments() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class Iterator<T> {
 }
 
 abstract class IterableMixin<T> {
   Iterator<T> get iterator;
 }
 
 class Test extends IterableMixin<int> {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 class Iterator<T> {
 }
 
 abstract class IterableMixin<T> {
   Iterator<T> get iterator;
 }
 
 class Test extends IterableMixin<int> {
   // TODO: implement iterator
   @override
   Iterator<int> get iterator => null;
 }
 ''');
   }
 
   test_createMissingOverrides_generics_typeParameters() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class ItemProvider<T> {
   List<T> getItems();
 }
 
 class Test<V> extends ItemProvider<V> {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 abstract class ItemProvider<T> {
   List<T> getItems();
 }
 
 class Test<V> extends ItemProvider<V> {
   @override
   List<V> getItems() {
     // TODO: implement getItems
   }
 }
 ''');
   }
 
   test_createMissingOverrides_getter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   get g1;
   int get g2;
 }
 
 class B extends A {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 abstract class A {
   get g1;
   int get g2;
 }
 
 class B extends A {
   // TODO: implement g1
   @override
   get g1 => null;
 
   // TODO: implement g2
   @override
   int get g2 => null;
 }
 ''');
   }
 
   test_createMissingOverrides_importPrefix() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as aaa;
 abstract class A {
   Map<aaa.Future, List<aaa.Future>> g(aaa.Future p);
 }
 
 class B extends A {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 import 'dart:async' as aaa;
 abstract class A {
   Map<aaa.Future, List<aaa.Future>> g(aaa.Future p);
 }
 
 class B extends A {
   @override
   Map<aaa.Future, List<aaa.Future>> g(aaa.Future p) {
     // TODO: implement g
   }
 }
 ''');
   }
 
   test_createMissingOverrides_mergeToField_getterSetter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int ma;
   void mb() {}
   double mc;
 }
 
 class B implements A {
 }
 ''');
     await assertHasFix(
@@ skipping 14 matching lines @@
 
   @override
   void mb() {
     // TODO: implement mb
   }
 }
 ''');
   }
 
   test_createMissingOverrides_method() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   m1();
   int m2();
   String m3(int p1, double p2, Map<int, List<String>> p3);
   String m4(p1, p2);
   String m5(p1, [int p2 = 2, int p3, p4 = 4]);
   String m6(p1, {int p2: 2, int p3, p4: 4});
 }
 
 class B extends A {
@@ skipping 52 matching lines @@
       expect(endString, contains('m1'));
       expect(endString, isNot(contains('m2')));
       expect(endString, isNot(contains('m3')));
       expect(endString, isNot(contains('m4')));
       expect(endString, isNot(contains('m5')));
       expect(endString, isNot(contains('m6')));
     }
   }
 
   test_createMissingOverrides_method_emptyClassBody() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   void foo();
 }
 
 class B extends A {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
         '''
 abstract class A {
   void foo();
 }
 
 class B extends A {
   @override
   void foo() {
     // TODO: implement foo
   }
 }
 ''');
   }
 
   test_createMissingOverrides_method_generic() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class C<T> {}
 class V<E> {}
 
 abstract class A {
   E1 foo<E1, E2 extends C<int>>(V<E2> v);
 }
 
 class B implements A {
 }
 ''');
@@ skipping 10 matching lines @@
 class B implements A {
   @override
   E1 foo<E1, E2 extends C<int>>(V<E2> v) {
     // TODO: implement foo
   }
 }
 ''');
   }
 
   test_createMissingOverrides_operator() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   int operator [](int index);
   void operator []=(int index, String value);
 }
 
 class B extends A {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_MISSING_OVERRIDES,
@@ skipping 11 matching lines @@
 
   @override
   void operator []=(int index, String value) {
     // TODO: implement []=
   }
 }
 ''');
   }
 
   test_createMissingOverrides_setter() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   set s1(x);
   set s2(int x);
   void set s3(String x);
 }
 
 class B extends A {
 }
 ''');
     await assertHasFix(
@@ skipping 18 matching lines @@
 
   @override
   set s3(String x) {
     // TODO: implement s3
   }
 }
 ''');
   }
 
   test_createNoSuchMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   m1();
   int m2();
 }
 
 class B extends A {
   existing() {}
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_NO_SUCH_METHOD,
         '''
 abstract class A {
   m1();
   int m2();
 }
 
 class B extends A {
   existing() {}
 
   noSuchMethod(Invocation invocation) => super.noSuchMethod(invocation);
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_cascadeSecond() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   B ma() => null;
 }
 class B {
   useFunction(int g(double a, String b)) {}
 }
 
 main() {
   A a = new A();
   a..ma().useFunction(test);
@@ skipping 13 matching lines @@
   A a = new A();
   a..ma().useFunction(test);
 }
 
 int test(double a, String b) {
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_coreFunction() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   useFunction(g: test);
 }
 useFunction({Function g}) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   useFunction(g: test);
 }
 useFunction({Function g}) {}
 
 test() {
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_dynamicArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   useFunction(test);
 }
 useFunction(int g(a, b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   useFunction(test);
 }
 useFunction(int g(a, b)) {}
 
 int test(a, b) {
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_function() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   useFunction(test);
 }
 useFunction(int g(double a, String b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   useFunction(test);
 }
 useFunction(int g(double a, String b)) {}
 
 int test(double a, String b) {
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_function_namedArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   useFunction(g: test);
 }
 useFunction({int g(double a, String b)}) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   useFunction(g: test);
@@ skipping 12 matching lines @@
 library libA;
 class A {}
 ''');
     addSource(
         '/libB.dart',
         r'''
 library libB;
 import 'libA.dart';
 useFunction(int g(A a)) {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'libB.dart';
 main() {
   useFunction(test);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 import 'libA.dart';
 import 'libB.dart';
 main() {
   useFunction(test);
 }
 
 int test(A a) {
 }
 ''');
   }
 
   test_creationFunction_forFunctionType_method_enclosingClass_static() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static foo() {
     useFunction(test);
   }
 }
 useFunction(int g(double a, String b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   static foo() {
     useFunction(test);
   }
 
   static int test(double a, String b) {
   }
 }
 useFunction(int g(double a, String b)) {}
 ''');
   }
 
   test_creationFunction_forFunctionType_method_enclosingClass_static2() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   var f;
   A() : f = useFunction(test);
 }
 useFunction(int g(double a, String b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   var f;
   A() : f = useFunction(test);
 
   static int test(double a, String b) {
   }
 }
 useFunction(int g(double a, String b)) {}
 ''');
   }
 
   test_creationFunction_forFunctionType_method_targetClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(A a) {
   useFunction(a.test);
 }
 class A {
 }
 useFunction(int g(double a, String b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 main(A a) {
   useFunction(a.test);
 }
 class A {
   int test(double a, String b) {
   }
 }
 useFunction(int g(double a, String b)) {}
 ''');
   }
 
   test_creationFunction_forFunctionType_method_targetClass_hasOtherMember() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(A a) {
   useFunction(a.test);
 }
 class A {
   m() {}
 }
 useFunction(int g(double a, String b)) {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 main(A a) {
   useFunction(a.test);
 }
 class A {
   m() {}
 
   int test(double a, String b) {
   }
 }
 useFunction(int g(double a, String b)) {}
 ''');
   }
 
   test_creationFunction_forFunctionType_notFunctionType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(A a) {
   useFunction(a.test);
 }
 typedef A();
 useFunction(g) {}
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
     await assertNoFix(DartFixKind.CREATE_FUNCTION);
   }
 
   test_creationFunction_forFunctionType_unknownTarget() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(A a) {
   useFunction(a.test);
 }
 class A {
 }
 useFunction(g) {}
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
   }
 
   test_expectedToken_semicolon() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   print(0)
 }
 ''');
     await assertHasFix(
         DartFixKind.INSERT_SEMICOLON,
         '''
 main() {
   print(0);
 }
 ''');
   }
 
   test_illegalAsyncReturnType_adjacentNodes() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async';
 var v;int main() async => 0;
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_RETURN_TYPE_FUTURE,
         '''
 import 'dart:async';
 var v;Future<int> main() async => 0;
 ''');
   }
 
   test_illegalAsyncReturnType_asyncLibrary_import() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 library main;
 int main() async {
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_RETURN_TYPE_FUTURE,
         '''
 library main;
 
 import 'dart:async';
 Future<int> main() async {
 }
 ''');
   }
 
   test_illegalAsyncReturnType_asyncLibrary_usePrefix() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as al;
 int main() async {
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_RETURN_TYPE_FUTURE,
         '''
 import 'dart:async' as al;
 al.Future<int> main() async {
 }
 ''');
   }
 
   test_illegalAsyncReturnType_complexTypeName() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async';
 List<int> main() async {
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_RETURN_TYPE_FUTURE,
         '''
 import 'dart:async';
 Future<List<int>> main() async {
 }
 ''');
   }
 
   test_illegalAsyncReturnType_void() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticTypeWarningCode.ILLEGAL_ASYNC_RETURN_TYPE;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async';
 void main() async {
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_RETURN_TYPE_FUTURE,
         '''
 import 'dart:async';
 Future main() async {
 }
 ''');
   }
 
   test_importLibraryPackage_preferDirectOverExport() async {
     _configureMyPkg({'b.dart': 'class Test {}', 'a.dart': "export 'b.dart';"});
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test test = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'package:my_pkg/b.dart';
 
 main() {
   Test test = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT2,
         '''
 import 'package:my_pkg/a.dart';
 
 main() {
   Test test = null;
 }
 ''');
   }
 
   test_importLibraryPackage_preferDirectOverExport_src() async {
     myPkgLibPath = '/my/src/packages/my_pkg/lib';
     _configureMyPkg({'b.dart': 'class Test {}', 'a.dart': "export 'b.dart';"});
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test test = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'package:my_pkg/b.dart';
 
 main() {
   Test test = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT2,
         '''
 import 'package:my_pkg/a.dart';
 
 main() {
   Test test = null;
 }
 ''');
   }
 
   test_importLibraryPackage_preferPublicOverPrivate() async {
     _configureMyPkg(
         {'src/a.dart': 'class Test {}', 'b.dart': "export 'src/a.dart';"});
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test test = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT2,
         '''
 import 'package:my_pkg/b.dart';
 
@@ skipping 14 matching lines @@
 
   test_importLibraryProject_withClass_annotation() async {
     addSource(
         '/lib.dart',
         '''
 library lib;
 class Test {
   const Test(int p);
 }
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 @Test(0)
 main() {
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 @Test(0)
 main() {
 }
 ''');
   }
 
   test_importLibraryProject_withClass_constInstanceCreation() async {
     addSource(
         '/lib.dart',
         '''
 class Test {
   const Test();
 }
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   const Test();
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
@@ skipping 11 matching lines @@
 library a;
 class One {}
 ''');
     addSource(
         '/project/bin/b.dart',
         '''
 library b;
 class One {}
 class Two {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'b.dart' show Two;
 main () {
   new Two();
   new One();
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'a.dart';
 import 'b.dart' show Two;
 main () {
   new Two();
   new One();
 }
 ''');
   }
 
   test_importLibraryProject_withClass_inParentFolder() async {
     testFile = '/project/bin/test.dart';
     addSource(
         '/project/lib.dart',
         '''
 library lib;
 class Test {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test t = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import '../lib.dart';
 
 main() {
   Test t = null;
 }
 ''');
   }
 
   test_importLibraryProject_withClass_inRelativeFolder() async {
     testFile = '/project/bin/test.dart';
     addSource(
         '/project/lib/sub/folder/lib.dart',
         '''
 library lib;
 class Test {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test t = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import '../lib/sub/folder/lib.dart';
 
 main() {
   Test t = null;
 }
 ''');
   }
 
   test_importLibraryProject_withClass_inSameFolder() async {
     testFile = '/project/bin/test.dart';
     addSource(
         '/project/bin/lib.dart',
         '''
 library lib;
 class Test {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Test t = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 main() {
   Test t = null;
 }
 ''');
   }
 
   test_importLibraryProject_withFunction() async {
     addSource(
         '/lib.dart',
         '''
 library lib;
 myFunction() {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   myFunction();
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 main() {
   myFunction();
 }
 ''');
   }
 
   test_importLibraryProject_withFunction_unresolvedMethod() async {
     addSource(
         '/lib.dart',
         '''
 library lib;
 myFunction() {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     myFunction();
   }
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 class A {
   main() {
     myFunction();
   }
 }
 ''');
   }
 
   test_importLibraryProject_withFunctionTypeAlias() async {
     testFile = '/project/bin/test.dart';
     addSource(
         '/project/bin/lib.dart',
         '''
 library lib;
 typedef MyFunction();
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   MyFunction t = null;
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 main() {
   MyFunction t = null;
 }
 ''');
   }
 
   test_importLibraryProject_withTopLevelVariable() async {
     addSource(
         '/lib.dart',
         '''
 library lib;
 int MY_VAR = 42;
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   print(MY_VAR);
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PROJECT1,
         '''
 import 'lib.dart';
 
 main() {
   print(MY_VAR);
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_AsExpression() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(p) {
   p as Future;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main(p) {
   p as Future;
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_invocationTarget() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Future.wait(null);
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main() {
   Future.wait(null);
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_IsExpression() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(p) {
   p is Future;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main(p) {
   p is Future;
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_itemOfList() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   var a = [Future];
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main() {
   var a = [Future];
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_itemOfList_inAnnotation() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == StaticWarningCode.UNDEFINED_IDENTIFIER;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class MyAnnotation {
   const MyAnnotation(a, b);
 }
 @MyAnnotation(int, const [Future])
 main() {}
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 class MyAnnotation {
   const MyAnnotation(a, b);
 }
 @MyAnnotation(int, const [Future])
 main() {}
 ''');
   }
 
   test_importLibrarySdk_withClass_typeAnnotation() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Future f = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main() {
   Future f = null;
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_typeAnnotation_PrefixedIdentifier() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Future.wait;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main() {
   Future.wait;
 }
 ''');
   }
 
   test_importLibrarySdk_withClass_typeArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   List<Future> futures = [];
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:async';
 
 main() {
   List<Future> futures = [];
 }
 ''');
   }
 
   test_importLibrarySdk_withTopLevelVariable() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   print(PI);
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:math';
 
 main() {
   print(PI);
 }
 ''');
   }
 
   test_importLibrarySdk_withTopLevelVariable_annotation() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 @PI
 main() {
 }
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SDK,
         '''
 import 'dart:math';
 
 @PI
 main() {
 }
 ''');
   }
 
   test_importLibraryShow_project() async {
     testFile = '/project/bin/test.dart';
     addSource(
         '/project/bin/lib.dart',
         '''
 class A {}
 class B {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'lib.dart' show A;
 main() {
   A a;
   B b;
 }
 ''');
     performAllAnalysisTasks();
     await assertNoFix(DartFixKind.IMPORT_LIBRARY_PROJECT1);
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SHOW,
         '''
 import 'lib.dart' show A, B;
 main() {
   A a;
   B b;
 }
 ''');
   }
 
   test_importLibraryShow_sdk() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' show Stream;
 main() {
   Stream s = null;
   Future f = null;
 }
 ''');
     await assertNoFix(DartFixKind.IMPORT_LIBRARY_SDK);
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_SHOW,
         '''
 import 'dart:async' show Future, Stream;
 main() {
   Stream s = null;
   Future f = null;
 }
 ''');
   }
 
   test_isNotNull() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(p) {
   p is! Null;
 }
 ''');
     await assertHasFix(
         DartFixKind.USE_NOT_EQ_NULL,
         '''
 main(p) {
   p != null;
 }
 ''');
   }
 
   test_isNull() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(p) {
   p is Null;
 }
 ''');
     await assertHasFix(
         DartFixKind.USE_EQ_EQ_NULL,
         '''
 main(p) {
   p == null;
 }
 ''');
   }
 
   test_makeEnclosingClassAbstract_declaresAbstractMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   m();
 }
 ''');
     await assertHasFix(
         DartFixKind.MAKE_CLASS_ABSTRACT,
         '''
 abstract class A {
   m();
 }
 ''');
   }
 
   test_makeEnclosingClassAbstract_inheritsAbstractMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 abstract class A {
   m();
 }
 class B extends A {
 }
 ''');
     await assertHasFix(
         DartFixKind.MAKE_CLASS_ABSTRACT,
         '''
 abstract class A {
   m();
 }
 abstract class B extends A {
 }
 ''');
   }
 
   test_makeFieldNotFinal_hasType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   final int fff = 1;
   main() {
     fff = 2;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.MAKE_FIELD_NOT_FINAL,
         '''
 class A {
   int fff = 1;
   main() {
     fff = 2;
   }
 }
 ''');
   }
 
   test_makeFieldNotFinal_noType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   final fff = 1;
   main() {
     fff = 2;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.MAKE_FIELD_NOT_FINAL,
         '''
 class A {
   var fff = 1;
   main() {
     fff = 2;
   }
 }
 ''');
   }
 
   test_noException_1() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(p) {
   p i s Null;
 }''');
     List<AnalysisError> errors = context.computeErrors(testSource);
     for (var error in errors) {
       await _computeFixes(error);
     }
   }
 
   test_nonBoolCondition_addNotNull() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(String p) {
   if (p) {
     print(p);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.ADD_NE_NULL,
         '''
 main(String p) {
   if (p != null) {
     print(p);
   }
 }
 ''');
   }
 
   test_removeDeadCode_condition() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(int p) {
   if (true || p > 5) {
     print(1);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_DEAD_CODE,
         '''
 main(int p) {
   if (true) {
     print(1);
   }
 }
 ''');
   }
 
   test_removeDeadCode_statements_one() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 int main() {
   print(0);
   return 42;
   print(1);
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_DEAD_CODE,
         '''
 int main() {
   print(0);
   return 42;
 }
 ''');
   }
 
   test_removeDeadCode_statements_two() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 int main() {
   print(0);
   return 42;
   print(1);
   print(2);
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_DEAD_CODE,
         '''
 int main() {
   print(0);
   return 42;
 }
 ''');
   }
 
   test_removeParentheses_inGetterDeclaration() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int get foo() => 0;
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_PARAMETERS_IN_GETTER_DECLARATION,
         '''
 class A {
   int get foo => 0;
 }
 ''');
   }
 
   test_removeParentheses_inGetterInvocation() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int get foo => 0;
 }
 main(A a) {
   a.foo();
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_PARENTHESIS_IN_GETTER_INVOCATION,
         '''
 class A {
   int get foo => 0;
 }
 main(A a) {
   a.foo;
 }
 ''');
   }
 
   test_removeUnnecessaryCast_assignment() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(Object p) {
   if (p is String) {
     String v = ((p as String));
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNNECESSARY_CAST,
         '''
 main(Object p) {
   if (p is String) {
     String v = p;
   }
 }
 ''');
   }
 
   test_removeUnusedCatchClause() async {
     errorFilter = (AnalysisError error) => true;
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   try {
     throw 42;
   } on int catch (e) {
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNUSED_CATCH_CLAUSE,
         '''
 main() {
   try {
     throw 42;
   } on int {
   }
 }
 ''');
   }
 
   test_removeUnusedCatchStack() async {
     errorFilter = (AnalysisError error) => true;
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   try {
     throw 42;
   } catch (e, stack) {
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNUSED_CATCH_STACK,
         '''
 main() {
   try {
     throw 42;
   } catch (e) {
   }
 }
 ''');
   }
 
   test_removeUnusedImport() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:math';
 main() {
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNUSED_IMPORT,
         '''
 main() {
 }
 ''');
   }
 
   test_removeUnusedImport_anotherImportOnLine() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:math'; import 'dart:async';
 
 main() {
   Future f;
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNUSED_IMPORT,
         '''
 import 'dart:async';
 
 main() {
   Future f;
 }
 ''');
   }
 
   test_removeUnusedImport_severalLines() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import
   'dart:math';
 main() {
 }
 ''');
     await assertHasFix(
         DartFixKind.REMOVE_UNUSED_IMPORT,
         '''
 main() {
 }
 ''');
   }
 
   test_replaceImportUri_inProject() async {
     testFile = '/project/bin/test.dart';
     addSource('/project/foo/bar/lib.dart', '');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'no/matter/lib.dart';
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.REPLACE_IMPORT_URI,
         '''
 import '../foo/bar/lib.dart';
 ''');
   }
 
   test_replaceImportUri_package() async {
     _configureMyPkg({'my_lib.dart': ''});
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'no/matter/my_lib.dart';
 ''');
     performAllAnalysisTasks();
     await assertHasFix(
         DartFixKind.REPLACE_IMPORT_URI,
         '''
 import 'package:my_pkg/my_lib.dart';
 ''');
   }
 
   test_replaceVarWithDynamic() async {
     errorFilter = (AnalysisError error) {
       return error.errorCode == ParserErrorCode.VAR_AS_TYPE_NAME;
     };
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   Map<String, var> m;
 }
 ''');
     await assertHasFix(
         DartFixKind.REPLACE_VAR_WITH_DYNAMIC,
         '''
 class A {
   Map<String, dynamic> m;
 }
 ''');
   }
 
   test_replaceWithConstInstanceCreation() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   const A();
 }
 const a = new A();
 ''');
     await assertHasFix(
         DartFixKind.USE_CONST,
         '''
 class A {
   const A();
 }
 const a = const A();
 ''');
   }
 
   test_undefinedClass_useSimilar_BAD_prefixed() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as c;
 main() {
   c.Fture v = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 import 'dart:async' as c;
 main() {
   c.Future v = null;
 }
 ''');
   }
 
   test_undefinedClass_useSimilar_fromImport() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   Stirng s = 'abc';
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 main() {
   String s = 'abc';
 }
 ''');
   }
 
   test_undefinedClass_useSimilar_fromThisLibrary() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class MyClass {}
 main() {
   MyCalss v = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class MyClass {}
 main() {
   MyClass v = null;
 }
 ''');
   }
 
   test_undefinedFunction_create_duplicateArgumentNames() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class C {
   int x;
 }
 
 foo(C c1, C c2) {
   bar(c1.x, c2.x);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 class C {
   int x;
 }
 
 foo(C c1, C c2) {
   bar(c1.x, c2.x);
 }
 
 void bar(int x, int x2) {
 }
 ''');
   }
 
   test_undefinedFunction_create_dynamicArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   dynamic v;
   test(v);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   dynamic v;
   test(v);
 }
 
 void test(v) {
 }
 ''');
   }
 
   test_undefinedFunction_create_dynamicReturnType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   dynamic v = test();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   dynamic v = test();
 }
 
 test() {
 }
 ''');
   }
 
   test_undefinedFunction_create_fromFunction() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   int v = myUndefinedFunction(1, 2.0, '3');
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   int v = myUndefinedFunction(1, 2.0, '3');
 }
 
 int myUndefinedFunction(int i, double d, String s) {
 }
 ''');
   }
 
   test_undefinedFunction_create_fromMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     int v = myUndefinedFunction(1, 2.0, '3');
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 class A {
   main() {
     int v = myUndefinedFunction(1, 2.0, '3');
   }
 }
 
 int myUndefinedFunction(int i, double d, String s) {
 }
 ''');
   }
 
   test_undefinedFunction_create_generic_BAD() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   Map<int, T> items;
   main() {
     process(items);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 class A<T> {
   Map<int, T> items;
   main() {
     process(items);
   }
 }
 
 void process(Map items) {
 }
 ''');
   }
 
   test_undefinedFunction_create_generic_OK() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   List<int> items;
   main() {
     process(items);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
@@ skipping 19 matching lines @@
   }
 
   test_undefinedFunction_create_importType() async {
     addSource(
         '/lib.dart',
         r'''
 library lib;
 import 'dart:async';
 Future getFuture() => null;
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'lib.dart';
 main() {
   test(getFuture());
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 import 'dart:async';
 import 'lib.dart';
 main() {
   test(getFuture());
 }
 
 void test(Future future) {
 }
 ''');
   }
 
   test_undefinedFunction_create_nullArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   test(null);
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   test(null);
 }
@@ skipping 14 matching lines @@
   test_undefinedFunction_create_returnType_bool_statements() async {
     await assert_undefinedFunction_create_returnType_bool("assert ( test() );");
     await assert_undefinedFunction_create_returnType_bool("if ( test() ) {}");
     await assert_undefinedFunction_create_returnType_bool(
         "while ( test() ) {}");
     await assert_undefinedFunction_create_returnType_bool(
         "do {} while ( test() );");
   }
 
   test_undefinedFunction_create_returnType_fromAssignment_eq() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   int v;
   v = myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   int v;
   v = myUndefinedFunction();
 }
 
 int myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_fromAssignment_plusEq() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   int v;
   v += myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   int v;
   v += myUndefinedFunction();
 }
 
 num myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_fromBinary_right() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   0 + myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   0 + myUndefinedFunction();
 }
 
 num myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_fromInitializer() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   int v = myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   int v = myUndefinedFunction();
 }
 
 int myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_fromInvocationArgument() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 foo(int p) {}
 main() {
   foo( myUndefinedFunction() );
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 foo(int p) {}
 main() {
   foo( myUndefinedFunction() );
 }
 
 int myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_fromReturn() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 int main() {
   return myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 int main() {
   return myUndefinedFunction();
 }
 
 int myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_create_returnType_void() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   myUndefinedFunction();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_FUNCTION,
         '''
 main() {
   myUndefinedFunction();
 }
 
 void myUndefinedFunction() {
 }
 ''');
   }
 
   test_undefinedFunction_useSimilar_fromImport() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   pritn(0);
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 main() {
   print(0);
 }
 ''');
   }
 
   test_undefinedFunction_useSimilar_prefixed_fromImport() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:core' as c;
 main() {
   c.prnt(42);
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 import 'dart:core' as c;
 main() {
   c.print(42);
 }
 ''');
   }
 
   test_undefinedFunction_useSimilar_prefixed_ignoreLocal() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as c;
 main() {
   c.main();
 }
 ''');
     await assertNoFix(DartFixKind.CHANGE_TO);
   }
 
   test_undefinedFunction_useSimilar_thisLibrary() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 myFunction() {}
 main() {
   myFuntcion();
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 myFunction() {}
 main() {
   myFunction();
 }
 ''');
   }
 
   test_undefinedGetter_useSimilar_hint() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
 }
 main(A a) {
   var x = a;
   print(x.myFild);
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
 }
 main(A a) {
   var x = a;
   print(x.myField);
 }
 ''');
   }
 
   test_undefinedGetter_useSimilar_qualified() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
 }
 main(A a) {
   print(a.myFild);
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
 }
 main(A a) {
   print(a.myField);
 }
 ''');
   }
 
   test_undefinedGetter_useSimilar_qualified_static() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static int MY_NAME = 1;
 }
 main() {
   A.MY_NAM;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   static int MY_NAME = 1;
 }
 main() {
   A.MY_NAME;
 }
 ''');
   }
 
   test_undefinedGetter_useSimilar_unqualified() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
   main() {
     print(myFild);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
   main() {
     print(myField);
   }
 }
 ''');
   }
 
   test_undefinedMethod_create_BAD_inSDK() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   List.foo();
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
   }
 
   test_undefinedMethod_create_BAD_targetIsEnum() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 enum MyEnum {A, B}
 main() {
   MyEnum.foo();
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
   }
 
   test_undefinedMethod_create_generic_BAD_argumentType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   B b;
   Map<int, T> items;
   main() {
     b.process(items);
   }
 }
 
 class B {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A<T> {
   B b;
   Map<int, T> items;
   main() {
     b.process(items);
   }
 }
 
 class B {
   void process(Map items) {}
 }
 ''');
   }
 
   test_undefinedMethod_create_generic_BAD_returnType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   main() {
     T t = new B().compute();
   }
 }
 
 class B {
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A<T> {
   main() {
     T t = new B().compute();
   }
 }
 
 class B {
   dynamic compute() {}
 }
 ''');
   }
 
   test_undefinedMethod_create_generic_OK_literal() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   B b;
   List<int> items;
   main() {
     b.process(items);
   }
 }
 
 class B {}
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   B b;
   List<int> items;
   main() {
     b.process(items);
   }
 }
 
 class B {
   void process(List<int> items) {}
 }
 ''');
   }
 
   test_undefinedMethod_create_generic_OK_local() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A<T> {
   List<T> items;
   main() {
     process(items);
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A<T> {
   List<T> items;
   main() {
     process(items);
   }
 
   void process(List<T> items) {}
 }
 ''');
   }
 
   test_undefinedMethod_createQualified_emptyClassBody() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {}
 main() {
   A.myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   static void myUndefinedMethod() {}
 }
 main() {
   A.myUndefinedMethod();
 }
 ''');
   }
 
   test_undefinedMethod_createQualified_fromClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main() {
   A.myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   static void myUndefinedMethod() {}
 }
 main() {
   A.myUndefinedMethod();
 }
 ''');
   }
 
   test_undefinedMethod_createQualified_fromClass_hasOtherMember() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   foo() {}
 }
 main() {
   A.myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   foo() {}
 
   static void myUndefinedMethod() {}
 }
 main() {
   A.myUndefinedMethod();
 }
 ''');
   }
 
   test_undefinedMethod_createQualified_fromInstance() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main(A a) {
   a.myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   void myUndefinedMethod() {}
 }
 main(A a) {
   a.myUndefinedMethod();
 }
 ''');
   }
 
   test_undefinedMethod_createQualified_targetIsFunctionType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 typedef A();
 main() {
   A.myUndefinedMethod();
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
   }
 
   test_undefinedMethod_createQualified_targetIsUnresolved() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   NoSuchClass.myUndefinedMethod();
 }
 ''');
     await assertNoFix(DartFixKind.CREATE_METHOD);
   }
 
   test_undefinedMethod_createUnqualified_duplicateArgumentNames() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class C {
   int x;
 }
 
 class D {
   foo(C c1, C c2) {
     bar(c1.x, c2.x);
   }
 }''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class C {
   int x;
 }
 
 class D {
   foo(C c1, C c2) {
     bar(c1.x, c2.x);
   }
 
   void bar(int x, int x2) {}
 }''');
   }
 
   test_undefinedMethod_createUnqualified_parameters() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     myUndefinedMethod(0, 1.0, '3');
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
@@ skipping 24 matching lines @@
     _assertLinkedGroup(change.linkedEditGroups[index++], ['d,']);
     _assertLinkedGroup(
         change.linkedEditGroups[index++],
         ['String s'],
         expectedSuggestions(LinkedEditSuggestionKind.TYPE,
             ['String', 'Object', 'Comparable<String>', 'Pattern']));
     _assertLinkedGroup(change.linkedEditGroups[index++], ['s)']);
   }
 
   test_undefinedMethod_createUnqualified_parameters_named() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     myUndefinedMethod(0, bbb: 1.0, ccc: '2');
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
@@ skipping 22 matching lines @@
         expectedSuggestions(LinkedEditSuggestionKind.TYPE,
             ['double', 'num', 'Object', 'Comparable<num>']));
     _assertLinkedGroup(
         change.linkedEditGroups[index++],
         ['String ccc'],
         expectedSuggestions(LinkedEditSuggestionKind.TYPE,
             ['String', 'Object', 'Comparable<String>', 'Pattern']));
   }
 
   test_undefinedMethod_createUnqualified_returnType() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   main() {
     int v = myUndefinedMethod();
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   main() {
     int v = myUndefinedMethod();
   }
 
   int myUndefinedMethod() {}
 }
 ''');
     // linked positions
     _assertLinkedGroup(change.linkedEditGroups[0], ['int myUndefinedMethod(']);
     _assertLinkedGroup(change.linkedEditGroups[1],
         ['myUndefinedMethod();', 'myUndefinedMethod() {']);
   }
 
   test_undefinedMethod_createUnqualified_staticFromField() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static var f = myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   static var f = myUndefinedMethod();
 
   static myUndefinedMethod() {}
 }
 ''');
   }
 
   test_undefinedMethod_createUnqualified_staticFromMethod() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   static main() {
     myUndefinedMethod();
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
 class A {
   static main() {
     myUndefinedMethod();
   }
 
   static void myUndefinedMethod() {}
 }
 ''');
   }
 
   test_undefinedMethod_hint_createQualified_fromInstance() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
 }
 main() {
   var a = new A();
   a.myUndefinedMethod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CREATE_METHOD,
         '''
@@ skipping 15 matching lines @@
 class D {
 }
 ''';
     addSource('/test2.dart', code2);
     addSource(
         '/test3.dart',
         r'''
 library test3;
 class E {}
 ''');
-    resolveTestUnit('''
+    await resolveTestUnit('''
 library test;
 import 'test2.dart' as aaa;
 main(aaa.D d, aaa.E e) {
   d.foo(e);
 }
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_METHOD, error);
     change = fix.change;
     // apply to "test2.dart"
@@ skipping 14 matching lines @@
   }
 
   test_undefinedMethod_parameterType_inTargetUnit() async {
     String code2 = r'''
 library test2;
 class D {
 }
 class E {}
 ''';
     addSource('/test2.dart', code2);
-    resolveTestUnit('''
+    await resolveTestUnit('''
 library test;
 import 'test2.dart' as test2;
 main(test2.D d, test2.E e) {
   d.foo(e);
 }
 ''');
     AnalysisError error = _findErrorToFix();
     fix = await _assertHasFix(DartFixKind.CREATE_METHOD, error);
     change = fix.change;
     // apply to "test2.dart"
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     SourceFileEdit fileEdit = change.edits[0];
     expect(fileEdit.file, '/test2.dart');
     expect(
         SourceEdit.applySequence(code2, fileEdit.edits),
         r'''
 library test2;
 class D {
   void foo(E e) {}
 }
 class E {}
 ''');
   }
 
   test_undefinedMethod_useSimilar_ignoreOperators() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main(Object object) {
   object.then();
 }
 ''');
     await assertNoFix(DartFixKind.CHANGE_TO);
   }
 
   test_undefinedMethod_useSimilar_qualified() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   myMethod() {}
 }
 main() {
   A a = new A();
   a.myMehtod();
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   myMethod() {}
 }
 main() {
   A a = new A();
   a.myMethod();
 }
 ''');
   }
 
   test_undefinedMethod_useSimilar_unqualified_superClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   myMethod() {}
 }
 class B extends A {
   main() {
     myMehtod();
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   myMethod() {}
 }
 class B extends A {
   main() {
     myMethod();
   }
 }
 ''');
   }
 
   test_undefinedMethod_useSimilar_unqualified_thisClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   myMethod() {}
   main() {
     myMehtod();
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   myMethod() {}
   main() {
     myMethod();
   }
 }
 ''');
   }
 
   test_undefinedSetter_useSimilar_hint() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
 }
 main(A a) {
   var x = a;
   x.myFild = 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
 }
 main(A a) {
   var x = a;
   x.myField = 42;
 }
 ''');
   }
 
   test_undefinedSetter_useSimilar_qualified() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
 }
 main(A a) {
   a.myFild = 42;
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
 }
 main(A a) {
   a.myField = 42;
 }
 ''');
   }
 
   test_undefinedSetter_useSimilar_unqualified() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 class A {
   int myField;
   main() {
     myFild = 42;
   }
 }
 ''');
     await assertHasFix(
         DartFixKind.CHANGE_TO,
         '''
 class A {
   int myField;
   main() {
     myField = 42;
   }
 }
 ''');
   }
 
   test_useEffectiveIntegerDivision() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 main() {
   var a = 5;
   var b = 2;
   print((a / b).toInt());
 }
 ''');
     await assertHasFix(
         DartFixKind.USE_EFFECTIVE_INTEGER_DIVISION,
         '''
 main() {
   var a = 5;
   var b = 2;
   print(a ~/ b);
 }
 ''');
   }
 
   test_useImportPrefix_withClass() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:async' as pref;
 main() {
   pref.Stream s = null;
   Future f = null;
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PREFIX,
         '''
 import 'dart:async' as pref;
 main() {
   pref.Stream s = null;
   pref.Future f = null;
 }
 ''');
   }
 
   test_useImportPrefix_withTopLevelVariable() async {
-    resolveTestUnit('''
+    await resolveTestUnit('''
 import 'dart:math' as pref;
 main() {
   print(pref.E);
   print(PI);
 }
 ''');
     await assertHasFix(
         DartFixKind.IMPORT_LIBRARY_PREFIX,
         '''
 import 'dart:math' as pref;
@@ skipping 11 matching lines @@
 
   Future applyFix(FixKind kind) async {
     fix = await _assertHasFix(kind, error);
     change = fix.change;
     // apply to "file"
     List<SourceFileEdit> fileEdits = change.edits;
     expect(fileEdits, hasLength(1));
     resultCode = SourceEdit.applySequence(testCode, change.edits[0].edits);
   }
 
-  void findLint(String src, String lintCode, {int length: 1}) {
+  Future<Null> findLint(String src, String lintCode, {int length: 1}) async {
     int errorOffset = src.indexOf('/*LINT*/');
-    resolveTestUnit(src.replaceAll('/*LINT*/', ''));
+    await resolveTestUnit(src.replaceAll('/*LINT*/', ''));
     error = new AnalysisError(
         resolutionMap.elementDeclaredByCompilationUnit(testUnit).source,
         errorOffset,
         length,
         new LintCode(lintCode, '<ignored>'));
   }
 
   test_lint_addMissingOverride_field() async {
     String src = '''
 class abstract Test {
   int get t;
 }
 class Sub extends Test {
   int /*LINT*/t = 42;
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class abstract Test {
   int get t;
 }
 class Sub extends Test {
   @override
   int t = 42;
 }
 ''');
   }
 
   test_lint_addMissingOverride_getter() async {
     String src = '''
 class Test {
   int get t => null;
 }
 class Sub extends Test {
   int get /*LINT*/t => null;
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   int get t => null;
 }
 class Sub extends Test {
   @override
   int get t => null;
 }
 ''');
   }
 
   test_lint_addMissingOverride_method() async {
     String src = '''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   void /*LINT*/t() { }
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   @override
   void t() { }
 }
 ''');
   }
 
   test_lint_addMissingOverride_method_with_doc_comment() async {
     String src = '''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /// Doc comment.
   void /*LINT*/t() { }
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /// Doc comment.
   @override
   void t() { }
 }
 ''');
   }
 
   test_lint_addMissingOverride_method_with_doc_comment_2() async {
     String src = '''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /**
    * Doc comment.
    */
   void /*LINT*/t() { }
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /**
    * Doc comment.
    */
   @override
   void t() { }
 }
 ''');
   }
 
   test_lint_addMissingOverride_method_with_doc_comment_and_metadata() async {
     String src = '''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /// Doc comment.
   @foo
   void /*LINT*/t() { }
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   /// Doc comment.
   @override
   @foo
   void t() { }
 }
 ''');
   }
 
   test_lint_addMissingOverride_method_with_non_doc_comment() async {
     String src = '''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   // Non-doc comment.
   void /*LINT*/t() { }
 }
 ''';
-    findLint(src, LintNames.annotate_overrides);
+    await findLint(src, LintNames.annotate_overrides);
 
     await applyFix(DartFixKind.LINT_ADD_OVERRIDE);
 
     verifyResult('''
 class Test {
   void t() { }
 }
 class Sub extends Test {
   // Non-doc comment.
   @override
   void t() { }
 }
 ''');
   }
 
   test_lint_removeInterpolationBraces() async {
     String src = r'''
 main() {
   var v = 42;
   print('v: /*LINT*/${ v}');
 }
 ''';
-    findLint(src, LintNames.unnecessary_brace_in_string_interp, length: 4);
+    await findLint(src, LintNames.unnecessary_brace_in_string_interp,
+        length: 4);
     await applyFix(DartFixKind.LINT_REMOVE_INTERPOLATION_BRACES);
     verifyResult(r'''
 main() {
   var v = 42;
   print('v: $v');
 }
 ''');
   }
 
   void verifyResult(String expectedResult) {
     expect(resultCode, expectedResult);
   }
 }