pkg/analysis_server/test/services/correction/assist_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.assist;

import 'package:analysis_server/edit/assist/assist_core.dart';
import 'package:analysis_server/src/plugin/server_plugin.dart';
import 'package:analysis_server/src/protocol.dart';
import 'package:analysis_server/src/services/correction/assist.dart';
import 'package:analyzer/src/generated/source.dart';
import 'package:plugin/manager.dart';
import 'package:test_reflective_loader/test_reflective_loader.dart';
import 'package:unittest/unittest.dart';

import '../../abstract_single_unit.dart';

main() {
  groupSep = ' | ';
  defineReflectiveTests(AssistProcessorTest);
}

@reflectiveTest
class AssistProcessorTest extends AbstractSingleUnitTest {
  int offset;
  int length;

  ServerPlugin plugin;
  Assist assist;
  SourceChange change;
  String resultCode;
  LinkedEditGroup linkedPositionGroup;

  /**
   * Asserts that there is an [Assist] of the given [kind] at [offset] which
   * produces the [expected] code when applied to [testCode].
   */
  void assertHasAssist(AssistKind kind, String expected) {
    assist = _assertHasAssist(kind);
    change = assist.change;
    // apply to "file"
    List<SourceFileEdit> fileEdits = change.edits;
    expect(fileEdits, hasLength(1));
    resultCode = SourceEdit.applySequence(testCode, change.edits[0].edits);
    // verify
    expect(resultCode, expected);
  }

  /**
   * Calls [assertHasAssist] at the offset of [offsetSearch] in [testCode].
   */
  void assertHasAssistAt(
      String offsetSearch, AssistKind kind, String expected) {
    offset = findOffset(offsetSearch);
    assertHasAssist(kind, expected);
  }

  /**
   * Asserts that there is no [Assist] of the given [kind] at [offset].
   */
  void assertNoAssist(AssistKind kind) {
    List<Assist> assists = computeAssists(
        plugin, context, testUnit.element.source, offset, length);
    for (Assist assist in assists) {
      if (assist.kind == kind) {
        throw fail('Unexpected assist $kind in\n${assists.join('\n')}');
      }
    }
  }

  /**
   * Calls [assertNoAssist] at the offset of [offsetSearch] in [testCode].
   */
  void assertNoAssistAt(String offsetSearch, AssistKind kind) {
    offset = findOffset(offsetSearch);
    assertNoAssist(kind);
  }

  Position expectedPosition(String search) {
    int offset = resultCode.indexOf(search);
    return new Position(testFile, offset);
  }

  List<Position> expectedPositions(List<String> patterns) {
    List<Position> positions = <Position>[];
    patterns.forEach((String search) {
      positions.add(expectedPosition(search));
    });
    return positions;
  }

  List<LinkedEditSuggestion> expectedSuggestions(
      LinkedEditSuggestionKind kind, List<String> values) {
    return values.map((value) {
      return new LinkedEditSuggestion(value, kind);
    }).toList();
  }

  void setUp() {
    super.setUp();
    offset = 0;
    length = 0;
    ExtensionManager manager = new ExtensionManager();
    plugin = new ServerPlugin();
    manager.processPlugins([plugin]);
  }

  void test_addTypeAnnotation_BAD_privateType_closureParameter() {
    addSource('/my_lib.dart', '''
library my_lib;
class A {}
class _B extends A {}
foo(f(_B p)) {}
''');
    resolveTestUnit('''
import 'my_lib.dart';
main() {
  foo((test) {});
}
 ''');
    assertNoAssistAt('test)', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_BAD_privateType_declaredIdentifier() {
    addSource('/my_lib.dart', '''
library my_lib;
class A {}
class _B extends A {}
List<_B> getValues() => [];
''');
    resolveTestUnit('''
import 'my_lib.dart';
class A<T> {
  main() {
    for (var item in getValues()) {
    }
  }
}
''');
    assertNoAssistAt('var item', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_BAD_privateType_list() {
    addSource('/my_lib.dart', '''
library my_lib;
class A {}
class _B extends A {}
List<_B> getValues() => [];
''');
    resolveTestUnit('''
import 'my_lib.dart';
main() {
  var v = getValues();
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_BAD_privateType_variable() {
    addSource('/my_lib.dart', '''
library my_lib;
class A {}
class _B extends A {}
_B getValue() => new _B();
''');
    resolveTestUnit('''
import 'my_lib.dart';
main() {
  var v = getValue();
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_classField_OK_final() {
    resolveTestUnit('''
class A {
  final f = 0;
}
''');
    assertHasAssistAt('final ', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class A {
  final int f = 0;
}
''');
  }

  void test_addTypeAnnotation_classField_OK_int() {
    resolveTestUnit('''
class A {
  var f = 0;
}
''');
    assertHasAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class A {
  int f = 0;
}
''');
  }

  void test_addTypeAnnotation_declaredIdentifier_BAD_hasTypeAnnotation() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
  }
}
''');
    assertNoAssistAt('item in', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_declaredIdentifier_BAD_inForEachBody() {
    resolveTestUnit('''
main(List<String> items) {
  for (var item in items) {
    42;
  }
}
''');
    assertNoAssistAt('42;', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_declaredIdentifier_BAD_unknownType() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main() {
  for (var item in unknownList) {
  }
}
''');
    assertNoAssistAt('item in', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_declaredIdentifier_generic_OK() {
    resolveTestUnit('''
class A<T> {
  main(List<List<T>> items) {
    for (var item in items) {
    }
  }
}
''');
    assertHasAssistAt('item in', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class A<T> {
  main(List<List<T>> items) {
    for (List<T> item in items) {
    }
  }
}
''');
  }

  void test_addTypeAnnotation_declaredIdentifier_OK() {
    resolveTestUnit('''
main(List<String> items) {
  for (var item in items) {
  }
}
''');
    // on identifier
    assertHasAssistAt('item in', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main(List<String> items) {
  for (String item in items) {
  }
}
''');
    // on "for"
    assertHasAssistAt('for (', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main(List<String> items) {
  for (String item in items) {
  }
}
''');
  }

  void test_addTypeAnnotation_declaredIdentifier_OK_addImport_dartUri() {
    addSource('/my_lib.dart', r'''
import 'dart:async';
List<Future<int>> getFutures() => null;
''');
    resolveTestUnit('''
import 'my_lib.dart';
main() {
  for (var future in getFutures()) {
  }
}
''');
    assertHasAssistAt('future in', DartAssistKind.ADD_TYPE_ANNOTATION, '''
import 'my_lib.dart';
import 'dart:async';
main() {
  for (Future<int> future in getFutures()) {
  }
}
''');
  }

  void test_addTypeAnnotation_declaredIdentifier_OK_final() {
    resolveTestUnit('''
main(List<String> items) {
  for (final item in items) {
  }
}
''');
    assertHasAssistAt('item in', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main(List<String> items) {
  for (final String item in items) {
  }
}
''');
  }

  void test_addTypeAnnotation_local_generic_OK_literal() {
    resolveTestUnit('''
class A {
  main(List<int> items) {
    var v = items;
  }
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class A {
  main(List<int> items) {
    List<int> v = items;
  }
}
''');
  }

  void test_addTypeAnnotation_local_generic_OK_local() {
    resolveTestUnit('''
class A<T> {
  main(List<T> items) {
    var v = items;
  }
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class A<T> {
  main(List<T> items) {
    List<T> v = items;
  }
}
''');
  }

  void test_addTypeAnnotation_local_OK_addImport_dartUri() {
    addSource('/my_lib.dart', r'''
import 'dart:async';
Future<int> getFutureInt() => null;
''');
    resolveTestUnit('''
import 'my_lib.dart';
main() {
  var v = getFutureInt();
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
import 'my_lib.dart';
import 'dart:async';
main() {
  Future<int> v = getFutureInt();
}
''');
  }

  void test_addTypeAnnotation_local_OK_addImport_notLibraryUnit() {
    // prepare library
    addSource('/my_lib.dart', r'''
import 'dart:async';
Future<int> getFutureInt() => null;
''');
    // prepare code
    String appCode = r'''
library my_app;
import 'my_lib.dart';
part 'test.dart';
''';
    testCode = r'''
part of my_app;
main() {
  var v = getFutureInt();
}
''';
    // add sources
    Source appSource = addSource('/app.dart', appCode);
    testSource = addSource('/test.dart', testCode);
    // resolve
    context.resolveCompilationUnit2(appSource, appSource);
    testUnit = context.resolveCompilationUnit2(testSource, appSource);
    assertNoErrorsInSource(testSource);
    testUnitElement = testUnit.element;
    testLibraryElement = testUnitElement.library;
    // prepare the assist
    offset = findOffset('v = ');
    assist = _assertHasAssist(DartAssistKind.ADD_TYPE_ANNOTATION);
    change = assist.change;
    // verify
    {
      var testFileEdit = change.getFileEdit('/app.dart');
      var resultCode = SourceEdit.applySequence(appCode, testFileEdit.edits);
      expect(resultCode, '''
library my_app;
import 'my_lib.dart';
import 'dart:async';
part 'test.dart';
''');
    }
    {
      var testFileEdit = change.getFileEdit('/test.dart');
      var resultCode = SourceEdit.applySequence(testCode, testFileEdit.edits);
      expect(resultCode, '''
part of my_app;
main() {
  Future<int> v = getFutureInt();
}
''');
    }
  }

  void test_addTypeAnnotation_local_OK_addImport_relUri() {
    addSource('/aa/bbb/lib_a.dart', r'''
class MyClass {}
''');
    addSource('/ccc/lib_b.dart', r'''
import '../aa/bbb/lib_a.dart';
MyClass newMyClass() => null;
''');
    resolveTestUnit('''
import 'ccc/lib_b.dart';
main() {
  var v = newMyClass();
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
import 'ccc/lib_b.dart';
import 'aa/bbb/lib_a.dart';
main() {
  MyClass v = newMyClass();
}
''');
  }

  void test_addTypeAnnotation_local_OK_Function() {
    resolveTestUnit('''
main() {
  var v = () => 1;
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  Function v = () => 1;
}
''');
  }

  void test_addTypeAnnotation_local_OK_int() {
    resolveTestUnit('''
main() {
  var v = 0;
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  int v = 0;
}
''');
  }

  void test_addTypeAnnotation_local_OK_List() {
    resolveTestUnit('''
main() {
  var v = <String>[];
}
''');
    assertHasAssistAt('v =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  List<String> v = <String>[];
}
''');
  }

  void test_addTypeAnnotation_local_OK_localType() {
    resolveTestUnit('''
class C {}
C f() => null;
main() {
  var x = f();
}
''');
    assertHasAssistAt('x =', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class C {}
C f() => null;
main() {
  C x = f();
}
''');
  }

  void test_addTypeAnnotation_local_OK_onInitializer() {
    resolveTestUnit('''
main() {
  var v = 123;
}
''');
    assertHasAssistAt('23', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  int v = 123;
}
''');
  }

  void test_addTypeAnnotation_local_OK_onName() {
    resolveTestUnit('''
main() {
  var abc = 0;
}
''');
    assertHasAssistAt('bc', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  int abc = 0;
}
''');
  }

  void test_addTypeAnnotation_local_OK_onVar() {
    resolveTestUnit('''
main() {
  var v = 0;
}
''');
    assertHasAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  int v = 0;
}
''');
  }

  void test_addTypeAnnotation_local_OK_onVariableDeclarationStatement() {
    resolveTestUnit('''
main() {
  var v = 123; // marker
}
''');
    assertHasAssistAt(' // marker', DartAssistKind.ADD_TYPE_ANNOTATION, '''
main() {
  int v = 123; // marker
}
''');
  }

  void test_addTypeAnnotation_local_wrong_hasTypeAnnotation() {
    resolveTestUnit('''
main() {
  int v = 42;
}
''');
    assertNoAssistAt(' = 42', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_local_wrong_multiple() {
    resolveTestUnit('''
main() {
  var a = 1, b = '';
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_local_wrong_noValue() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main() {
  var v;
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_local_wrong_null() {
    resolveTestUnit('''
main() {
  var v = null;
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_local_wrong_unknown() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main() {
  var v = unknownVar;
}
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_OK_privateType_sameLibrary() {
    resolveTestUnit('''
class _A {}
_A getValue() => new _A();
main() {
  var v = getValue();
}
''');
    assertHasAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION, '''
class _A {}
_A getValue() => new _A();
main() {
  _A v = getValue();
}
''');
  }

  void test_addTypeAnnotation_parameter_BAD_hasExplicitType() {
    resolveTestUnit('''
foo(f(int p)) {}
main() {
  foo((num test) {});
}
''');
    assertNoAssistAt('test', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_parameter_BAD_noPropagatedType() {
    resolveTestUnit('''
foo(f(p)) {}
main() {
  foo((test) {});
}
''');
    assertNoAssistAt('test', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_parameter_OK() {
    resolveTestUnit('''
foo(f(int p)) {}
main() {
  foo((test) {});
}
''');
    assertHasAssistAt('test', DartAssistKind.ADD_TYPE_ANNOTATION, '''
foo(f(int p)) {}
main() {
  foo((int test) {});
}
''');
  }

  void test_addTypeAnnotation_topLevelField_OK_int() {
    resolveTestUnit('''
var V = 0;
''');
    assertHasAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION, '''
int V = 0;
''');
  }

  void test_addTypeAnnotation_topLevelField_wrong_multiple() {
    resolveTestUnit('''
var A = 1, V = '';
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_addTypeAnnotation_topLevelField_wrong_noValue() {
    resolveTestUnit('''
var V;
''');
    assertNoAssistAt('var ', DartAssistKind.ADD_TYPE_ANNOTATION);
  }

  void test_assignToLocalVariable() {
    resolveTestUnit('''
main() {
  List<int> bytes;
  readBytes();
}
List<int> readBytes() => <int>[];
''');
    assertHasAssistAt('readBytes();', DartAssistKind.ASSIGN_TO_LOCAL_VARIABLE,
        '''
main() {
  List<int> bytes;
  var readBytes = readBytes();
}
List<int> readBytes() => <int>[];
''');
    _assertLinkedGroup(change.linkedEditGroups[0], [
      'readBytes = '
    ], expectedSuggestions(
        LinkedEditSuggestionKind.VARIABLE, ['list', 'bytes2', 'readBytes']));
  }

  void test_assignToLocalVariable_alreadyAssignment() {
    resolveTestUnit('''
main() {
  var vvv;
  vvv = 42;
}
''');
    assertNoAssistAt('vvv =', DartAssistKind.ASSIGN_TO_LOCAL_VARIABLE);
  }

  void test_assignToLocalVariable_invocationArgument() {
    resolveTestUnit(r'''
main() {
  f(12345);
}
int f(p) {}
''');
    assertNoAssistAt('345', DartAssistKind.ASSIGN_TO_LOCAL_VARIABLE);
  }

  void test_assignToLocalVariable_throw() {
    resolveTestUnit('''
main() {
  throw 42;
}
''');
    assertNoAssistAt('throw ', DartAssistKind.ASSIGN_TO_LOCAL_VARIABLE);
  }

  void test_assignToLocalVariable_void() {
    resolveTestUnit('''
main() {
  f();
}
void f() {}
''');
    assertNoAssistAt('f();', DartAssistKind.ASSIGN_TO_LOCAL_VARIABLE);
  }

  void test_convertToBlockBody_OK_closure() {
    resolveTestUnit('''
setup(x) {}
main() {
  setup(() => print('done'));
}
''');
    assertHasAssistAt('() => print', DartAssistKind.CONVERT_INTO_BLOCK_BODY, '''
setup(x) {}
main() {
  setup(() {
    return print('done');
  });
}
''');
  }

  void test_convertToBlockBody_OK_constructor() {
    resolveTestUnit('''
class A {
  factory A() => null;
}
''');
    assertHasAssistAt('A()', DartAssistKind.CONVERT_INTO_BLOCK_BODY, '''
class A {
  factory A() {
    return null;
  }
}
''');
  }

  void test_convertToBlockBody_OK_method() {
    resolveTestUnit('''
class A {
  mmm() => 123;
}
''');
    assertHasAssistAt('mmm()', DartAssistKind.CONVERT_INTO_BLOCK_BODY, '''
class A {
  mmm() {
    return 123;
  }
}
''');
  }

  void test_convertToBlockBody_OK_onName() {
    resolveTestUnit('''
fff() => 123;
''');
    assertHasAssistAt('fff()', DartAssistKind.CONVERT_INTO_BLOCK_BODY, '''
fff() {
  return 123;
}
''');
  }

  void test_convertToBlockBody_OK_onValue() {
    resolveTestUnit('''
fff() => 123;
''');
    assertHasAssistAt('23;', DartAssistKind.CONVERT_INTO_BLOCK_BODY, '''
fff() {
  return 123;
}
''');
  }

  void test_convertToBlockBody_wrong_noEnclosingFunction() {
    resolveTestUnit('''
var v = 123;
''');
    assertNoAssistAt('v =', DartAssistKind.CONVERT_INTO_BLOCK_BODY);
  }

  void test_convertToBlockBody_wrong_notExpressionBlock() {
    resolveTestUnit('''
fff() {
  return 123;
}
''');
    assertNoAssistAt('fff() {', DartAssistKind.CONVERT_INTO_BLOCK_BODY);
  }

  void test_convertToExpressionBody_OK_closure() {
    resolveTestUnit('''
setup(x) {}
main() {
  setup(() {
    return 42;
  });
}
''');
    assertHasAssistAt('42;', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
setup(x) {}
main() {
  setup(() => 42);
}
''');
  }

  void test_convertToExpressionBody_OK_constructor() {
    resolveTestUnit('''
class A {
  factory A() {
    return null;
  }
}
''');
    assertHasAssistAt('A()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
class A {
  factory A() => null;
}
''');
  }

  void test_convertToExpressionBody_OK_function_onBlock() {
    resolveTestUnit('''
fff() {
  return 42;
}
''');
    assertHasAssistAt('{', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
fff() => 42;
''');
  }

  void test_convertToExpressionBody_OK_function_onName() {
    resolveTestUnit('''
fff() {
  return 42;
}
''');
    assertHasAssistAt('ff()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
fff() => 42;
''');
  }

  void test_convertToExpressionBody_OK_method_onBlock() {
    resolveTestUnit('''
class A {
  m() { // marker
    return 42;
  }
}
''');
    assertHasAssistAt('{ // marker',
        DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
class A {
  m() => 42;
}
''');
  }

  void test_convertToExpressionBody_OK_topFunction_onReturnStatement() {
    resolveTestUnit('''
fff() {
  return 42;
}
''');
    assertHasAssistAt('return', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY, '''
fff() => 42;
''');
  }

  void test_convertToExpressionBody_wrong_already() {
    resolveTestUnit('''
fff() => 42;
''');
    assertNoAssistAt('fff()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY);
  }

  void test_convertToExpressionBody_wrong_moreThanOneStatement() {
    resolveTestUnit('''
fff() {
  var v = 42;
  return v;
}
''');
    assertNoAssistAt('fff()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY);
  }

  void test_convertToExpressionBody_wrong_noEnclosingFunction() {
    resolveTestUnit('''
var V = 42;
''');
    assertNoAssistAt('V = ', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY);
  }

  void test_convertToExpressionBody_wrong_noReturn() {
    resolveTestUnit('''
fff() {
  var v = 42;
}
''');
    assertNoAssistAt('fff()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY);
  }

  void test_convertToExpressionBody_wrong_noReturnValue() {
    resolveTestUnit('''
fff() {
  return;
}
''');
    assertNoAssistAt('fff()', DartAssistKind.CONVERT_INTO_EXPRESSION_BODY);
  }

  void test_convertToFieldParameter_BAD_additionalUse() {
    resolveTestUnit('''
class A {
  int aaa2;
  int bbb2;
  A(int aaa) : aaa2 = aaa, bbb2 = aaa;
}
''');
    assertNoAssistAt('aaa)', DartAssistKind.CONVERT_TO_FIELD_PARAMETER);
  }

  void test_convertToFieldParameter_BAD_notPureAssignment() {
    resolveTestUnit('''
class A {
  int aaa2;
  A(int aaa) : aaa2 = aaa * 2;
}
''');
    assertNoAssistAt('aaa)', DartAssistKind.CONVERT_TO_FIELD_PARAMETER);
  }

  void test_convertToFieldParameter_OK_firstInitializer() {
    resolveTestUnit('''
class A {
  double aaa2;
  int bbb2;
  A(int aaa, int bbb) : aaa2 = aaa, bbb2 = bbb;
}
''');
    assertHasAssistAt('aaa, ', DartAssistKind.CONVERT_TO_FIELD_PARAMETER, '''
class A {
  double aaa2;
  int bbb2;
  A(this.aaa2, int bbb) : bbb2 = bbb;
}
''');
  }

  void test_convertToFieldParameter_OK_onParameterName_inInitializer() {
    resolveTestUnit('''
class A {
  int test2;
  A(int test) : test2 = test {
  }
}
''');
    assertHasAssistAt('test {', DartAssistKind.CONVERT_TO_FIELD_PARAMETER, '''
class A {
  int test2;
  A(this.test2) {
  }
}
''');
  }

  void test_convertToFieldParameter_OK_onParameterName_inParameters() {
    resolveTestUnit('''
class A {
  int test;
  A(int test) : test = test {
  }
}
''');
    assertHasAssistAt('test)', DartAssistKind.CONVERT_TO_FIELD_PARAMETER, '''
class A {
  int test;
  A(this.test) {
  }
}
''');
  }

  void test_convertToFieldParameter_OK_secondInitializer() {
    resolveTestUnit('''
class A {
  double aaa2;
  int bbb2;
  A(int aaa, int bbb) : aaa2 = aaa, bbb2 = bbb;
}
''');
    assertHasAssistAt('bbb)', DartAssistKind.CONVERT_TO_FIELD_PARAMETER, '''
class A {
  double aaa2;
  int bbb2;
  A(int aaa, this.bbb2) : aaa2 = aaa;
}
''');
  }

  void test_convertToForIndex_BAD_bodyNotBlock() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) print(item);
}
''');
    assertNoAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX);
  }

  void test_convertToForIndex_BAD_doesNotDeclareVariable() {
    resolveTestUnit('''
main(List<String> items) {
  String item;
  for (item in items) {
    print(item);
  }
}
''');
    assertNoAssistAt('for (item', DartAssistKind.CONVERT_INTO_FOR_INDEX);
  }

  void test_convertToForIndex_BAD_iterableIsNotVariable() {
    resolveTestUnit('''
main() {
  for (String item in ['a', 'b', 'c']) {
    print(item);
  }
}
''');
    assertNoAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX);
  }

  void test_convertToForIndex_BAD_iterableNotList() {
    resolveTestUnit('''
main(Iterable<String> items) {
  for (String item in items) {
    print(item);
  }
}
''');
    assertNoAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX);
  }

  void test_convertToForIndex_BAD_usesIJK() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    print(item);
    int i, j, k;
  }
}
''');
    assertNoAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX);
  }

  void test_convertToForIndex_OK_onDeclaredIdentifier_name() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    print(item);
  }
}
''');
    assertHasAssistAt('item in', DartAssistKind.CONVERT_INTO_FOR_INDEX, '''
main(List<String> items) {
  for (int i = 0; i < items.length; i++) {
    String item = items[i];
    print(item);
  }
}
''');
  }

  void test_convertToForIndex_OK_onDeclaredIdentifier_type() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    print(item);
  }
}
''');
    assertHasAssistAt('tring item', DartAssistKind.CONVERT_INTO_FOR_INDEX, '''
main(List<String> items) {
  for (int i = 0; i < items.length; i++) {
    String item = items[i];
    print(item);
  }
}
''');
  }

  void test_convertToForIndex_OK_onFor() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    print(item);
  }
}
''');
    assertHasAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX, '''
main(List<String> items) {
  for (int i = 0; i < items.length; i++) {
    String item = items[i];
    print(item);
  }
}
''');
  }

  void test_convertToForIndex_OK_usesI() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    int i = 0;
  }
}
''');
    assertHasAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX, '''
main(List<String> items) {
  for (int j = 0; j < items.length; j++) {
    String item = items[j];
    int i = 0;
  }
}
''');
  }

  void test_convertToForIndex_OK_usesIJ() {
    resolveTestUnit('''
main(List<String> items) {
  for (String item in items) {
    print(item);
    int i = 0, j = 1;
  }
}
''');
    assertHasAssistAt('for (String', DartAssistKind.CONVERT_INTO_FOR_INDEX, '''
main(List<String> items) {
  for (int k = 0; k < items.length; k++) {
    String item = items[k];
    print(item);
    int i = 0, j = 1;
  }
}
''');
  }

  void test_convertToIsNot_OK_childOfIs_left() {
    resolveTestUnit('''
main(p) {
  !(p is String);
}
''');
    assertHasAssistAt('p is', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  p is! String;
}
''');
  }

  void test_convertToIsNot_OK_childOfIs_right() {
    resolveTestUnit('''
main(p) {
  !(p is String);
}
''');
    assertHasAssistAt('String)', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  p is! String;
}
''');
  }

  void test_convertToIsNot_OK_is() {
    resolveTestUnit('''
main(p) {
  !(p is String);
}
''');
    assertHasAssistAt('is String', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  p is! String;
}
''');
  }

  void test_convertToIsNot_OK_is_higherPrecedencePrefix() {
    resolveTestUnit('''
main(p) {
  !!(p is String);
}
''');
    assertHasAssistAt('is String', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  !(p is! String);
}
''');
  }

  void test_convertToIsNot_OK_is_not_higherPrecedencePrefix() {
    resolveTestUnit('''
main(p) {
  !!(p is String);
}
''');
    assertHasAssistAt('!(p', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  !(p is! String);
}
''');
  }

  void test_convertToIsNot_OK_not() {
    resolveTestUnit('''
main(p) {
  !(p is String);
}
''');
    assertHasAssistAt('!(p', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  p is! String;
}
''');
  }

  void test_convertToIsNot_OK_parentheses() {
    resolveTestUnit('''
main(p) {
  !(p is String);
}
''');
    assertHasAssistAt('(p is', DartAssistKind.CONVERT_INTO_IS_NOT, '''
main(p) {
  p is! String;
}
''');
  }

  void test_convertToIsNot_wrong_is_alreadyIsNot() {
    resolveTestUnit('''
main(p) {
  p is! String;
}
''');
    assertNoAssistAt('is!', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_is_noEnclosingParenthesis() {
    resolveTestUnit('''
main(p) {
  p is String;
}
''');
    assertNoAssistAt('is String', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_is_noPrefix() {
    resolveTestUnit('''
main(p) {
  (p is String);
}
''');
    assertNoAssistAt('is String', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_is_notIsExpression() {
    resolveTestUnit('''
main(p) {
  123 + 456;
}
''');
    assertNoAssistAt('123 +', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_is_notTheNotOperator() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main(p) {
  ++(p is String);
}
''');
    assertNoAssistAt('is String', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_not_alreadyIsNot() {
    resolveTestUnit('''
main(p) {
  !(p is! String);
}
''');
    assertNoAssistAt('!(p', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_not_noEnclosingParenthesis() {
    resolveTestUnit('''
main(p) {
  !p;
}
''');
    assertNoAssistAt('!p', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_not_notIsExpression() {
    resolveTestUnit('''
main(p) {
  !(p == null);
}
''');
    assertNoAssistAt('!(p', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNot_wrong_not_notTheNotOperator() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main(p) {
  ++(p is String);
}
''');
    assertNoAssistAt('++(', DartAssistKind.CONVERT_INTO_IS_NOT);
  }

  void test_convertToIsNotEmpty_OK_on_isEmpty() {
    resolveTestUnit('''
main(String str) {
  !str.isEmpty;
}
''');
    assertHasAssistAt('isEmpty', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY, '''
main(String str) {
  str.isNotEmpty;
}
''');
  }

  void test_convertToIsNotEmpty_OK_on_str() {
    resolveTestUnit('''
main(String str) {
  !str.isEmpty;
}
''');
    assertHasAssistAt('str.', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY, '''
main(String str) {
  str.isNotEmpty;
}
''');
  }

  void test_convertToIsNotEmpty_OK_propertyAccess() {
    resolveTestUnit('''
main(String str) {
  !'text'.isEmpty;
}
''');
    assertHasAssistAt('isEmpty', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY, '''
main(String str) {
  'text'.isNotEmpty;
}
''');
  }

  void test_convertToIsNotEmpty_wrong_noBang() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main(String str) {
  ~str.isEmpty;
}
''');
    assertNoAssistAt('isEmpty;', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY);
  }

  void test_convertToIsNotEmpty_wrong_noIsNotEmpty() {
    resolveTestUnit('''
class A {
  bool get isEmpty => false;
}
main(A a) {
  !a.isEmpty;
}
''');
    assertNoAssistAt('isEmpty;', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY);
  }

  void test_convertToIsNotEmpty_wrong_notInPrefixExpression() {
    resolveTestUnit('''
main(String str) {
  str.isEmpty;
}
''');
    assertNoAssistAt('isEmpty;', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY);
  }

  void test_convertToIsNotEmpty_wrong_notIsEmpty() {
    resolveTestUnit('''
main(int p) {
  !p.isEven;
}
''');
    assertNoAssistAt('isEven;', DartAssistKind.CONVERT_INTO_IS_NOT_EMPTY);
  }

  void test_convertToNormalParameter_OK_dynamic() {
    resolveTestUnit('''
class A {
  var test;
  A(this.test) {
  }
}
''');
    assertHasAssistAt('test)', DartAssistKind.CONVERT_TO_NORMAL_PARAMETER, '''
class A {
  var test;
  A(test) : test = test {
  }
}
''');
  }

  void test_convertToNormalParameter_OK_firstInitializer() {
    resolveTestUnit('''
class A {
  int test;
  A(this.test) {
  }
}
''');
    assertHasAssistAt('test)', DartAssistKind.CONVERT_TO_NORMAL_PARAMETER, '''
class A {
  int test;
  A(int test) : test = test {
  }
}
''');
  }

  void test_convertToNormalParameter_OK_secondInitializer() {
    resolveTestUnit('''
class A {
  double aaa;
  int bbb;
  A(this.bbb) : aaa = 1.0;
}
''');
    assertHasAssistAt('bbb)', DartAssistKind.CONVERT_TO_NORMAL_PARAMETER, '''
class A {
  double aaa;
  int bbb;
  A(int bbb) : aaa = 1.0, bbb = bbb;
}
''');
  }

  void test_encapsulateField_BAD_alreadyPrivate() {
    resolveTestUnit('''
class A {
  int _test = 42;
}
main(A a) {
  print(a._test);
}
''');
    assertNoAssistAt('_test =', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_BAD_final() {
    resolveTestUnit('''
class A {
  final int test = 42;
}
''');
    assertNoAssistAt('test =', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_BAD_multipleFields() {
    resolveTestUnit('''
class A {
  int aaa, bbb, ccc;
}
main(A a) {
  print(a.bbb);
}
''');
    assertNoAssistAt('bbb, ', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_BAD_notOnName() {
    resolveTestUnit('''
class A {
  int test = 1 + 2 + 3;
}
''');
    assertNoAssistAt('+ 2', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_BAD_parseError() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
class A {
  int; // marker
}
main(A a) {
  print(a.test);
}
''');
    assertNoAssistAt('; // marker', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_BAD_static() {
    resolveTestUnit('''
class A {
  static int test = 42;
}
''');
    assertNoAssistAt('test =', DartAssistKind.ENCAPSULATE_FIELD);
  }

  void test_encapsulateField_OK_hasType() {
    resolveTestUnit('''
class A {
  int test = 42;
  A(this.test);
}
main(A a) {
  print(a.test);
}
''');
    assertHasAssistAt('test = 42', DartAssistKind.ENCAPSULATE_FIELD, '''
class A {
  int _test = 42;

  int get test => _test;

  void set test(int test) {
    _test = test;
  }
  A(this._test);
}
main(A a) {
  print(a.test);
}
''');
  }

  void test_encapsulateField_OK_noType() {
    resolveTestUnit('''
class A {
  var test = 42;
}
main(A a) {
  print(a.test);
}
''');
    assertHasAssistAt('test = 42', DartAssistKind.ENCAPSULATE_FIELD, '''
class A {
  var _test = 42;

  get test => _test;

  void set test(test) {
    _test = test;
  }
}
main(A a) {
  print(a.test);
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_compare() {
    Map<String, String> operatorMap = {
      '<': '>',
      '<=': '>=',
      '>': '<',
      '>=': '<='
    };
    operatorMap.forEach((initialOperator, resultOperator) {
      resolveTestUnit('''
bool main(int a, int b) {
  return a $initialOperator b;
}
''');
      assertHasAssistAt(initialOperator, DartAssistKind.EXCHANGE_OPERANDS, '''
bool main(int a, int b) {
  return b $resultOperator a;
}
''');
    });
  }

  void test_exchangeBinaryExpressionArguments_OK_extended_mixOperator_1() {
    resolveTestUnit('''
main() {
  1 * 2 * 3 + 4;
}
''');
    assertHasAssistAt('* 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 * 3 * 1 + 4;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_extended_mixOperator_2() {
    resolveTestUnit('''
main() {
  1 + 2 - 3 + 4;
}
''');
    assertHasAssistAt('+ 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 1 - 3 + 4;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_extended_sameOperator_afterFirst() {
    resolveTestUnit('''
main() {
  1 + 2 + 3;
}
''');
    assertHasAssistAt('+ 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 3 + 1;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_extended_sameOperator_afterSecond() {
    resolveTestUnit('''
main() {
  1 + 2 + 3;
}
''');
    assertHasAssistAt('+ 3', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  3 + 1 + 2;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_simple_afterOperator() {
    resolveTestUnit('''
main() {
  1 + 2;
}
''');
    assertHasAssistAt(' 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 1;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_simple_beforeOperator() {
    resolveTestUnit('''
main() {
  1 + 2;
}
''');
    assertHasAssistAt('+ 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 1;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_simple_fullSelection() {
    resolveTestUnit('''
main() {
  1 + 2;
}
''');
    length = '1 + 2'.length;
    assertHasAssistAt('1 + 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 1;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_OK_simple_withLength() {
    resolveTestUnit('''
main() {
  1 + 2;
}
''');
    length = 2;
    assertHasAssistAt('+ 2', DartAssistKind.EXCHANGE_OPERANDS, '''
main() {
  2 + 1;
}
''');
  }

  void test_exchangeBinaryExpressionArguments_wrong_extraLength() {
    resolveTestUnit('''
main() {
  111 + 222;
}
''');
    length = 3;
    assertNoAssistAt('+ 222', DartAssistKind.EXCHANGE_OPERANDS);
  }

  void test_exchangeBinaryExpressionArguments_wrong_onOperand() {
    resolveTestUnit('''
main() {
  111 + 222;
}
''');
    length = 3;
    assertNoAssistAt('11 +', DartAssistKind.EXCHANGE_OPERANDS);
  }

  void test_exchangeBinaryExpressionArguments_wrong_selectionWithBinary() {
    resolveTestUnit('''
main() {
  1 + 2 + 3;
}
''');
    length = '1 + 2 + 3'.length;
    assertNoAssistAt('1 + 2 + 3', DartAssistKind.EXCHANGE_OPERANDS);
  }

  void test_importAddShow_BAD_hasShow() {
    resolveTestUnit('''
import 'dart:math' show PI;
main() {
  PI;
}
''');
    assertNoAssistAt('import ', DartAssistKind.IMPORT_ADD_SHOW);
  }

  void test_importAddShow_BAD_unresolvedUri() {
    resolveTestUnit('''
import '/no/such/lib.dart';
''');
    assertNoAssistAt('import ', DartAssistKind.IMPORT_ADD_SHOW);
  }

  void test_importAddShow_BAD_unused() {
    resolveTestUnit('''
import 'dart:math';
''');
    assertNoAssistAt('import ', DartAssistKind.IMPORT_ADD_SHOW);
  }

  void test_importAddShow_OK_hasUnresolvedIdentifier() {
    resolveTestUnit('''
import 'dart:math';
main(x) {
  PI;
  return x.foo();
}
''');
    assertHasAssistAt('import ', DartAssistKind.IMPORT_ADD_SHOW, '''
import 'dart:math' show PI;
main(x) {
  PI;
  return x.foo();
}
''');
  }

  void test_importAddShow_OK_onDirective() {
    resolveTestUnit('''
import 'dart:math';
main() {
  PI;
  E;
  max(1, 2);
}
''');
    assertHasAssistAt('import ', DartAssistKind.IMPORT_ADD_SHOW, '''
import 'dart:math' show E, PI, max;
main() {
  PI;
  E;
  max(1, 2);
}
''');
  }

  void test_importAddShow_OK_onUri() {
    resolveTestUnit('''
import 'dart:math';
main() {
  PI;
  E;
  max(1, 2);
}
''');
    assertHasAssistAt('art:math', DartAssistKind.IMPORT_ADD_SHOW, '''
import 'dart:math' show E, PI, max;
main() {
  PI;
  E;
  max(1, 2);
}
''');
  }

  void test_introduceLocalTestedType_BAD_notBlock() {
    resolveTestUnit('''
main(p) {
  if (p is String)
    print('not a block');
}
''');
    assertNoAssistAt('if (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE);
  }

  void test_introduceLocalTestedType_BAD_notIsExpression() {
    resolveTestUnit('''
main(p) {
  if (p == null) {
  }
}
''');
    assertNoAssistAt('if (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE);
  }

  void test_introduceLocalTestedType_OK_if_is() {
    resolveTestUnit('''
class MyTypeName {}
main(p) {
  if (p is MyTypeName) {
  }
  p = null;
}
''');
    String expected = '''
class MyTypeName {}
main(p) {
  if (p is MyTypeName) {
    MyTypeName myTypeName = p;
  }
  p = null;
}
''';
    assertHasAssistAt(
        'is MyType', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
    _assertLinkedGroup(change.linkedEditGroups[0], [
      'myTypeName = '
    ], expectedSuggestions(
        LinkedEditSuggestionKind.VARIABLE, ['myTypeName', 'typeName', 'name']));
    // another good location
    assertHasAssistAt(
        'if (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
  }

  void test_introduceLocalTestedType_OK_if_isNot() {
    resolveTestUnit('''
class MyTypeName {}
main(p) {
  if (p is! MyTypeName) {
    return;
  }
}
''');
    String expected = '''
class MyTypeName {}
main(p) {
  if (p is! MyTypeName) {
    return;
  }
  MyTypeName myTypeName = p;
}
''';
    assertHasAssistAt(
        'is! MyType', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
    _assertLinkedGroup(change.linkedEditGroups[0], [
      'myTypeName = '
    ], expectedSuggestions(
        LinkedEditSuggestionKind.VARIABLE, ['myTypeName', 'typeName', 'name']));
    // another good location
    assertHasAssistAt(
        'if (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
  }

  void test_introduceLocalTestedType_OK_while() {
    resolveTestUnit('''
main(p) {
  while (p is String) {
  }
  p = null;
}
''');
    String expected = '''
main(p) {
  while (p is String) {
    String s = p;
  }
  p = null;
}
''';
    assertHasAssistAt(
        'is String', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
    assertHasAssistAt(
        'while (p', DartAssistKind.INTRODUCE_LOCAL_CAST_TYPE, expected);
  }

  void test_invalidSelection() {
    resolveTestUnit('');
    List<Assist> assists =
        computeAssists(plugin, context, testUnit.element.source, -1, 0);
    expect(assists, isEmpty);
  }

  void test_invertIfStatement_blocks() {
    resolveTestUnit('''
main() {
  if (true) {
    0;
  } else {
    1;
  }
}
''');
    assertHasAssistAt('if (', DartAssistKind.INVERT_IF_STATEMENT, '''
main() {
  if (false) {
    1;
  } else {
    0;
  }
}
''');
  }

  void test_invertIfStatement_statements() {
    resolveTestUnit('''
main() {
  if (true)
    0;
  else
    1;
}
''');
    assertHasAssistAt('if (', DartAssistKind.INVERT_IF_STATEMENT, '''
main() {
  if (false)
    1;
  else
    0;
}
''');
  }

  void test_joinIfStatementInner_OK_conditionAndOr() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2 || 3 == 3) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && (2 == 2 || 3 == 3)) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_conditionInvocation() {
    resolveTestUnit('''
main() {
  if (isCheck()) {
    if (2 == 2) {
      print(0);
    }
  }
}
bool isCheck() => false;
''');
    assertHasAssistAt('if (isCheck', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (isCheck() && 2 == 2) {
    print(0);
  }
}
bool isCheck() => false;
''');
  }

  void test_joinIfStatementInner_OK_conditionOrAnd() {
    resolveTestUnit('''
main() {
  if (1 == 1 || 2 == 2) {
    if (3 == 3) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if ((1 == 1 || 2 == 2) && 3 == 3) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_onCondition() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_simpleConditions_block_block() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_simpleConditions_block_single() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2)
      print(0);
  }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_simpleConditions_single_blockMulti() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(1);
      print(2);
      print(3);
    }
  }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(1);
    print(2);
    print(3);
  }
}
''');
  }

  void test_joinIfStatementInner_OK_simpleConditions_single_blockOne() {
    resolveTestUnit('''
main() {
  if (1 == 1)
    if (2 == 2) {
      print(0);
    }
}
''');
    assertHasAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementInner_wrong_innerNotIf() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    print(0);
  }
}
''');
    assertNoAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER);
  }

  void test_joinIfStatementInner_wrong_innerWithElse() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    } else {
      print(1);
    }
  }
}
''');
    assertNoAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER);
  }

  void test_joinIfStatementInner_wrong_targetNotIf() {
    resolveTestUnit('''
main() {
  print(0);
}
''');
    assertNoAssistAt('print', DartAssistKind.JOIN_IF_WITH_INNER);
  }

  void test_joinIfStatementInner_wrong_targetWithElse() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  } else {
    print(1);
  }
}
''');
    assertNoAssistAt('if (1 ==', DartAssistKind.JOIN_IF_WITH_INNER);
  }

  void test_joinIfStatementOuter_OK_conditionAndOr() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2 || 3 == 3) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (2 ==', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && (2 == 2 || 3 == 3)) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_conditionInvocation() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (isCheck()) {
      print(0);
    }
  }
}
bool isCheck() => false;
''');
    assertHasAssistAt('if (isCheck', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && isCheck()) {
    print(0);
  }
}
bool isCheck() => false;
''');
  }

  void test_joinIfStatementOuter_OK_conditionOrAnd() {
    resolveTestUnit('''
main() {
  if (1 == 1 || 2 == 2) {
    if (3 == 3) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (3 == 3', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if ((1 == 1 || 2 == 2) && 3 == 3) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_onCondition() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_simpleConditions_block_block() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  }
}
''');
    assertHasAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_simpleConditions_block_single() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2)
      print(0);
  }
}
''');
    assertHasAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_simpleConditions_single_blockMulti() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(1);
      print(2);
      print(3);
    }
  }
}
''');
    assertHasAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(1);
    print(2);
    print(3);
  }
}
''');
  }

  void test_joinIfStatementOuter_OK_simpleConditions_single_blockOne() {
    resolveTestUnit('''
main() {
  if (1 == 1)
    if (2 == 2) {
      print(0);
    }
}
''');
    assertHasAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER, '''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
}
''');
  }

  void test_joinIfStatementOuter_wrong_outerNotIf() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    print(0);
  }
}
''');
    assertNoAssistAt('if (1 == 1', DartAssistKind.JOIN_IF_WITH_OUTER);
  }

  void test_joinIfStatementOuter_wrong_outerWithElse() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    }
  } else {
    print(1);
  }
}
''');
    assertNoAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER);
  }

  void test_joinIfStatementOuter_wrong_targetNotIf() {
    resolveTestUnit('''
main() {
  print(0);
}
''');
    assertNoAssistAt('print', DartAssistKind.JOIN_IF_WITH_OUTER);
  }

  void test_joinIfStatementOuter_wrong_targetWithElse() {
    resolveTestUnit('''
main() {
  if (1 == 1) {
    if (2 == 2) {
      print(0);
    } else {
      print(1);
    }
  }
}
''');
    assertNoAssistAt('if (2 == 2', DartAssistKind.JOIN_IF_WITH_OUTER);
  }

  void test_joinVariableDeclaration_onAssignment_OK() {
    resolveTestUnit('''
main() {
  var v;
  v = 1;
}
''');
    assertHasAssistAt('v =', DartAssistKind.JOIN_VARIABLE_DECLARATION, '''
main() {
  var v = 1;
}
''');
  }

  void test_joinVariableDeclaration_onAssignment_wrong_hasInitializer() {
    resolveTestUnit('''
main() {
  var v = 1;
  v = 2;
}
''');
    assertNoAssistAt('v = 2', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notAdjacent() {
    resolveTestUnit('''
main() {
  var v;
  var bar;
  v = 1;
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notAssignment() {
    resolveTestUnit('''
main() {
  var v;
  v += 1;
}
''');
    assertNoAssistAt('v += 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notDeclaration() {
    resolveTestUnit('''
main(var v) {
  v = 1;
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notLeftArgument() {
    resolveTestUnit('''
main() {
  var v;
  1 + v; // marker
}
''');
    assertNoAssistAt('v; // marker', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notOneVariable() {
    resolveTestUnit('''
main() {
  var v, v2;
  v = 1;
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notResolved() {
    verifyNoTestUnitErrors = false;
    resolveTestUnit('''
main() {
  var v;
  x = 1;
}
''');
    assertNoAssistAt('x = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onAssignment_wrong_notSameBlock() {
    resolveTestUnit('''
main() {
  var v;
  {
    v = 1;
  }
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_OK_onName() {
    resolveTestUnit('''
main() {
  var v;
  v = 1;
}
''');
    assertHasAssistAt('v;', DartAssistKind.JOIN_VARIABLE_DECLARATION, '''
main() {
  var v = 1;
}
''');
  }

  void test_joinVariableDeclaration_onDeclaration_OK_onType() {
    resolveTestUnit('''
main() {
  int v;
  v = 1;
}
''');
    assertHasAssistAt('int v', DartAssistKind.JOIN_VARIABLE_DECLARATION, '''
main() {
  int v = 1;
}
''');
  }

  void test_joinVariableDeclaration_onDeclaration_OK_onVar() {
    resolveTestUnit('''
main() {
  var v;
  v = 1;
}
''');
    assertHasAssistAt('var v', DartAssistKind.JOIN_VARIABLE_DECLARATION, '''
main() {
  var v = 1;
}
''');
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_hasInitializer() {
    resolveTestUnit('''
main() {
  var v = 1;
  v = 2;
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_lastStatement() {
    resolveTestUnit('''
main() {
  if (true)
    var v;
}
''');
    assertNoAssistAt('v;', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_nextNotAssignmentExpression() {
    resolveTestUnit('''
main() {
  var v;
  42;
}
''');
    assertNoAssistAt('v;', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_nextNotExpressionStatement() {
    resolveTestUnit('''
main() {
  var v;
  if (true) return;
}
''');
    assertNoAssistAt('v;', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_nextNotPureAssignment() {
    resolveTestUnit('''
main() {
  var v;
  v += 1;
}
''');
    assertNoAssistAt('v;', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_joinVariableDeclaration_onDeclaration_wrong_notOneVariable() {
    resolveTestUnit('''
main() {
  var v, v2;
  v = 1;
}
''');
    assertNoAssistAt('v, ', DartAssistKind.JOIN_VARIABLE_DECLARATION);
  }

  void test_removeTypeAnnotation_classField_OK() {
    resolveTestUnit('''
class A {
  int v = 1;
}
''');
    assertHasAssistAt('v = ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
class A {
  var v = 1;
}
''');
  }

  void test_removeTypeAnnotation_classField_OK_final() {
    resolveTestUnit('''
class A {
  final int v = 1;
}
''');
    assertHasAssistAt('v = ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
class A {
  final v = 1;
}
''');
  }

  void test_removeTypeAnnotation_localVariable_OK() {
    resolveTestUnit('''
main() {
  int a = 1, b = 2;
}
''');
    assertHasAssistAt('int ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
main() {
  var a = 1, b = 2;
}
''');
  }

  void test_removeTypeAnnotation_localVariable_OK_const() {
    resolveTestUnit('''
main() {
  const int v = 1;
}
''');
    assertHasAssistAt('int ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
main() {
  const v = 1;
}
''');
  }

  void test_removeTypeAnnotation_localVariable_OK_final() {
    resolveTestUnit('''
main() {
  final int v = 1;
}
''');
    assertHasAssistAt('int ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
main() {
  final v = 1;
}
''');
  }

  void test_removeTypeAnnotation_topLevelVariable_OK() {
    resolveTestUnit('''
int V = 1;
''');
    assertHasAssistAt('int ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
var V = 1;
''');
  }

  void test_removeTypeAnnotation_topLevelVariable_OK_final() {
    resolveTestUnit('''
final int V = 1;
''');
    assertHasAssistAt('int ', DartAssistKind.REMOVE_TYPE_ANNOTATION, '''
final V = 1;
''');
  }

  void test_replaceConditionalWithIfElse_OK_assignment() {
    resolveTestUnit('''
main() {
  var v;
  v = true ? 111 : 222;
}
''');
    // on conditional
    assertHasAssistAt('11 :', DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE,
        '''
main() {
  var v;
  if (true) {
    v = 111;
  } else {
    v = 222;
  }
}
''');
    // on variable
    assertHasAssistAt('v =', DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE,
        '''
main() {
  var v;
  if (true) {
    v = 111;
  } else {
    v = 222;
  }
}
''');
  }

  void test_replaceConditionalWithIfElse_OK_return() {
    resolveTestUnit('''
main() {
  return true ? 111 : 222;
}
''');
    assertHasAssistAt('return ',
        DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE, '''
main() {
  if (true) {
    return 111;
  } else {
    return 222;
  }
}
''');
  }

  void test_replaceConditionalWithIfElse_OK_variableDeclaration() {
    resolveTestUnit('''
main() {
  int a = 1, vvv = true ? 111 : 222, b = 2;
}
''');
    assertHasAssistAt('11 :', DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE,
        '''
main() {
  int a = 1, vvv, b = 2;
  if (true) {
    vvv = 111;
  } else {
    vvv = 222;
  }
}
''');
  }

  void test_replaceConditionalWithIfElse_wrong_noEnclosingStatement() {
    resolveTestUnit('''
var v = true ? 111 : 222;
''');
    assertNoAssistAt('? 111', DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE);
  }

  void test_replaceConditionalWithIfElse_wrong_notConditional() {
    resolveTestUnit('''
main() {
  var v = 42;
}
''');
    assertNoAssistAt('v = 42', DartAssistKind.REPLACE_CONDITIONAL_WITH_IF_ELSE);
  }

  void test_replaceIfElseWithConditional_OK_assignment() {
    resolveTestUnit('''
main() {
  int vvv;
  if (true) {
    vvv = 111;
  } else {
    vvv = 222;
  }
}
''');
    assertHasAssistAt('if (true)',
        DartAssistKind.REPLACE_IF_ELSE_WITH_CONDITIONAL, '''
main() {
  int vvv;
  vvv = true ? 111 : 222;
}
''');
  }

  void test_replaceIfElseWithConditional_OK_return() {
    resolveTestUnit('''
main() {
  if (true) {
    return 111;
  } else {
    return 222;
  }
}
''');
    assertHasAssistAt('if (true)',
        DartAssistKind.REPLACE_IF_ELSE_WITH_CONDITIONAL, '''
main() {
  return true ? 111 : 222;
}
''');
  }

  void test_replaceIfElseWithConditional_wrong_expressionVsReturn() {
    resolveTestUnit('''
main() {
  if (true) {
    print(42);
  } else {
    return;
  }
}
''');
    assertNoAssistAt('else', DartAssistKind.REPLACE_IF_ELSE_WITH_CONDITIONAL);
  }

  void test_replaceIfElseWithConditional_wrong_notIfStatement() {
    resolveTestUnit('''
main() {
  print(0);
}
''');
    assertNoAssistAt('print', DartAssistKind.REPLACE_IF_ELSE_WITH_CONDITIONAL);
  }

  void test_replaceIfElseWithConditional_wrong_notSingleStatememt() {
    resolveTestUnit('''
main() {
  int vvv;
  if (true) {
    print(0);
    vvv = 111;
  } else {
    print(0);
    vvv = 222;
  }
}
''');
    assertNoAssistAt(
        'if (true)', DartAssistKind.REPLACE_IF_ELSE_WITH_CONDITIONAL);
  }

  void test_splitAndCondition_OK_innerAndExpression() {
    resolveTestUnit('''
main() {
  if (1 == 1 && 2 == 2 && 3 == 3) {
    print(0);
  }
}
''');
    assertHasAssistAt('&& 2 == 2', DartAssistKind.SPLIT_AND_CONDITION, '''
main() {
  if (1 == 1) {
    if (2 == 2 && 3 == 3) {
      print(0);
    }
  }
}
''');
  }

  void test_splitAndCondition_OK_thenBlock() {
    resolveTestUnit('''
main() {
  if (true && false) {
    print(0);
    if (3 == 3) {
      print(1);
    }
  }
}
''');
    assertHasAssistAt('&& false', DartAssistKind.SPLIT_AND_CONDITION, '''
main() {
  if (true) {
    if (false) {
      print(0);
      if (3 == 3) {
        print(1);
      }
    }
  }
}
''');
  }

  void test_splitAndCondition_OK_thenStatement() {
    resolveTestUnit('''
main() {
  if (true && false)
    print(0);
}
''');
    assertHasAssistAt('&& false', DartAssistKind.SPLIT_AND_CONDITION, '''
main() {
  if (true)
    if (false)
      print(0);
}
''');
  }

  void test_splitAndCondition_wrong() {
    resolveTestUnit('''
main() {
  if (1 == 1 && 2 == 2) {
    print(0);
  }
  print(3 == 3 && 4 == 4);
}
''');
    // not binary expression
    assertNoAssistAt('main() {', DartAssistKind.SPLIT_AND_CONDITION);
    // selection is not empty and includes more than just operator
    {
      length = 5;
      assertNoAssistAt('&& 2 == 2', DartAssistKind.SPLIT_AND_CONDITION);
    }
  }

  void test_splitAndCondition_wrong_hasElse() {
    resolveTestUnit('''
main() {
  if (1 == 1 && 2 == 2) {
    print(1);
  } else {
    print(2);
  }
}
''');
    assertNoAssistAt('&& 2', DartAssistKind.SPLIT_AND_CONDITION);
  }

  void test_splitAndCondition_wrong_notAnd() {
    resolveTestUnit('''
main() {
  if (1 == 1 || 2 == 2) {
    print(0);
  }
}
''');
    assertNoAssistAt('|| 2', DartAssistKind.SPLIT_AND_CONDITION);
  }

  void test_splitAndCondition_wrong_notPartOfIf() {
    resolveTestUnit('''
main() {
  print(1 == 1 && 2 == 2);
}
''');
    assertNoAssistAt('&& 2', DartAssistKind.SPLIT_AND_CONDITION);
  }

  void test_splitAndCondition_wrong_notTopLevelAnd() {
    resolveTestUnit('''
main() {
  if (true || (1 == 1 && 2 == 2)) {
    print(0);
  }
  if (true && (3 == 3 && 4 == 4)) {
    print(0);
  }
}
''');
    assertNoAssistAt('&& 2', DartAssistKind.SPLIT_AND_CONDITION);
    assertNoAssistAt('&& 4', DartAssistKind.SPLIT_AND_CONDITION);
  }

  void test_splitVariableDeclaration_OK_onName() {
    resolveTestUnit('''
main() {
  var v = 1;
}
''');
    assertHasAssistAt('v =', DartAssistKind.SPLIT_VARIABLE_DECLARATION, '''
main() {
  var v;
  v = 1;
}
''');
  }

  void test_splitVariableDeclaration_OK_onType() {
    resolveTestUnit('''
main() {
  int v = 1;
}
''');
    assertHasAssistAt('int ', DartAssistKind.SPLIT_VARIABLE_DECLARATION, '''
main() {
  int v;
  v = 1;
}
''');
  }

  void test_splitVariableDeclaration_OK_onVar() {
    resolveTestUnit('''
main() {
  var v = 1;
}
''');
    assertHasAssistAt('var ', DartAssistKind.SPLIT_VARIABLE_DECLARATION, '''
main() {
  var v;
  v = 1;
}
''');
  }

  void test_splitVariableDeclaration_wrong_notOneVariable() {
    resolveTestUnit('''
main() {
  var v = 1, v2;
}
''');
    assertNoAssistAt('v = 1', DartAssistKind.SPLIT_VARIABLE_DECLARATION);
  }

  void test_surroundWith_block() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_BLOCK, '''
main() {
// start
  {
    print(0);
    print(1);
  }
// end
}
''');
  }

  void test_surroundWith_doWhile() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_DO_WHILE, '''
main() {
// start
  do {
    print(0);
    print(1);
  } while (condition);
// end
}
''');
  }

  void test_surroundWith_for() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_FOR, '''
main() {
// start
  for (var v = init; condition; increment) {
    print(0);
    print(1);
  }
// end
}
''');
  }

  void test_surroundWith_forIn() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_FOR_IN, '''
main() {
// start
  for (var item in iterable) {
    print(0);
    print(1);
  }
// end
}
''');
  }

  void test_surroundWith_if() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_IF, '''
main() {
// start
  if (condition) {
    print(0);
    print(1);
  }
// end
}
''');
  }

  void test_surroundWith_tryCatch() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_TRY_CATCH, '''
main() {
// start
  try {
    print(0);
    print(1);
  } on Exception catch (e) {
    // TODO
  }
// end
}
''');
  }

  void test_surroundWith_tryFinally() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_TRY_FINALLY, '''
main() {
// start
  try {
    print(0);
    print(1);
  } finally {
    // TODO
  }
// end
}
''');
  }

  void test_surroundWith_while() {
    resolveTestUnit('''
main() {
// start
  print(0);
  print(1);
// end
}
''');
    _setStartEndSelection();
    assertHasAssist(DartAssistKind.SURROUND_WITH_WHILE, '''
main() {
// start
  while (condition) {
    print(0);
    print(1);
  }
// end
}
''');
  }

  /**
   * Computes assists and verifies that there is an assist of the given kind.
   */
  Assist _assertHasAssist(AssistKind kind) {
    List<Assist> assists = computeAssists(
        plugin, context, testUnit.element.source, offset, length);
    for (Assist assist in assists) {
      if (assist.kind == kind) {
        return assist;
      }
    }
    throw fail('Expected to find assist $kind in\n${assists.join('\n')}');
  }

  void _assertLinkedGroup(LinkedEditGroup group, List<String> expectedStrings,
      [List<LinkedEditSuggestion> expectedSuggestions]) {
    List<Position> expectedPositions = _findResultPositions(expectedStrings);
    expect(group.positions, unorderedEquals(expectedPositions));
    if (expectedSuggestions != null) {
      expect(group.suggestions, unorderedEquals(expectedSuggestions));
    }
  }

  List<Position> _findResultPositions(List<String> searchStrings) {
    List<Position> positions = <Position>[];
    for (String search in searchStrings) {
      int offset = resultCode.indexOf(search);
      positions.add(new Position(testFile, offset));
    }
    return positions;
  }

  void _setStartEndSelection() {
    offset = findOffset('// start\n') + '// start\n'.length;
    length = findOffset('// end') - offset;
  }
}