// Copyright (c) 2019, the Dart project authors. Please see the AUTHORS file
// for details. All rights reserved. Use of this source code is governed by a
// BSD-style license that can be found in the LICENSE file.

import 'package:analyzer/dart/element/type.dart';
import 'package:analyzer/src/dart/element/type.dart';
import 'package:analyzer/src/error/codes.dart';
import 'package:test/test.dart';
import 'package:test_reflective_loader/test_reflective_loader.dart';

import 'context_collection_resolution.dart';

main() {
  defineReflectiveSuite(() {
    defineReflectiveTests(LocalVariableResolutionTest);
    defineReflectiveTests(LocalVariableResolutionWithNullSafetyTest);
  });
}

@reflectiveTest
class LocalVariableResolutionTest extends PubPackageResolutionTest {
  test_demoteTypeParameterType() async {
    await assertNoErrorsInCode('''
void f<T>(T a, T b) {
  if (a is String) {
    var o = a;
    o = b;
    o; // ref
  }
}
''');

    var type = findNode.simple('o; // ref').staticType;
    assertType(type, 'T');
    _assertPromotedBound(type, isNull);
  }

  test_element_block() async {
    await assertErrorsInCode(r'''
void f() {
  int x = 0;
}
''', [
      error(HintCode.UNUSED_LOCAL_VARIABLE, 17, 1),
    ]);

    var x = findElement.localVar('x');
    expect(x.isConst, isFalse);
    expect(x.isFinal, isFalse);
    expect(x.isLate, isFalse);
    expect(x.isStatic, isFalse);
  }

  test_element_const() async {
    await assertErrorsInCode(r'''
void f() {
  const int x = 0;
}
''', [
      error(HintCode.UNUSED_LOCAL_VARIABLE, 23, 1),
    ]);

    var x = findElement.localVar('x');
    expect(x.isConst, isTrue);
    expect(x.isFinal, isFalse);
    expect(x.isLate, isFalse);
    expect(x.isStatic, isFalse);
  }

  test_element_final() async {
    await assertErrorsInCode(r'''
void f() {
  final int x = 0;
}
''', [
      error(HintCode.UNUSED_LOCAL_VARIABLE, 23, 1),
    ]);

    var x = findElement.localVar('x');
    expect(x.isConst, isFalse);
    expect(x.isFinal, isTrue);
    expect(x.isLate, isFalse);
    expect(x.isStatic, isFalse);
  }

  test_element_ifStatement() async {
    await assertErrorsInCode(r'''
void f() {
  if (1 > 2)
    int x = 0;
}
''', [
      error(HintCode.UNUSED_LOCAL_VARIABLE, 32, 1),
    ]);

    var x = findElement.localVar('x');
    expect(x.isConst, isFalse);
    expect(x.isFinal, isFalse);
    expect(x.isLate, isFalse);
    expect(x.isStatic, isFalse);
  }

  void _assertPromotedBound(DartType type, Matcher promotedBound) {
    if (type is TypeParameterTypeImpl) {
      expect(type.promotedBound, promotedBound);
    }
  }
}

@reflectiveTest
class LocalVariableResolutionWithNullSafetyTest
    extends LocalVariableResolutionTest with WithNullSafetyMixin {
  test_element_late() async {
    await assertErrorsInCode(r'''
void f() {
  late int x = 0;
}
''', [
      error(HintCode.UNUSED_LOCAL_VARIABLE, 22, 1),
    ]);

    var x = findElement.localVar('x');
    expect(x.isConst, isFalse);
    expect(x.isFinal, isFalse);
    expect(x.isLate, isTrue);
    expect(x.isStatic, isFalse);
  }

  test_nonNullifyType() async {
    newFile('$testPackageLibPath/a.dart', content: r'''
// @dart = 2.7
var a = 0;
''');

    await assertNoErrorsInCode('''
import 'a.dart';

void f() {
  var x = a;
  x;
}
''');

    var x = findElement.localVar('x');
    assertType(x.type, 'int');
  }
}