pkg/analyzer/test/src/diagnostics/duplicate_variable_pattern_test.dart

// Copyright (c) 2022, 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:test_reflective_loader/test_reflective_loader.dart';

import '../dart/resolution/context_collection_resolution.dart';

main() {
  defineReflectiveSuite(() {
    defineReflectiveTests(DuplicateVariablePatternTest);
  });
}

@reflectiveTest
class DuplicateVariablePatternTest extends PubPackageResolutionTest {
  test_ifCase() async {
    var result = await resolveTestCodeWithDiagnostics(r'''
void f(int x) {
  if (x case var a && var a) {
//               ^
// [context 1] The first definition of this name.
//                        ^
// [diag.duplicateVariablePattern][context 1] The variable 'a' is already defined in this pattern.
    a;
  }
}
''');

    var node = result.findNode.singleIfStatement;
    assertResolvedNodeText(node, r'''
IfStatement
  ifKeyword: if
  leftParenthesis: (
  expression2: SimpleIdentifier
    token: x
    element: <testLibrary>::@function::f::@formalParameter::x
    staticType: int
  caseClause: CaseClause
    caseKeyword: case
    guardedPattern: GuardedPattern
      pattern: LogicalAndPattern
        leftOperand: DeclaredVariablePattern
          keyword: var
          name: a
          declaredFragment: isPublic a@33
            element: hasImplicitType isPublic
              type: int
          matchedValueType: int
        operator: &&
        rightOperand: DeclaredVariablePattern
          keyword: var
          name: a
          declaredFragment: isPublic a@42
            element: hasImplicitType isPublic
              type: int
          matchedValueType: int
        matchedValueType: int
  rightParenthesis: )
  thenStatement: Block
    leftBracket: {
    statements
      ExpressionStatement
        expression2: SimpleIdentifier
          token: a
          element: a@33
          staticType: int
        semicolon: ;
    rightBracket: }
''');
  }

  test_switchStatement() async {
    var result = await resolveTestCodeWithDiagnostics(r'''
void f(int x) {
  switch (x) {
    case var a && var a:
//           ^
// [context 1] The first definition of this name.
//                    ^
// [diag.duplicateVariablePattern][context 1] The variable 'a' is already defined in this pattern.
      a;
  }
}
''');

    var node = result.findNode.singleSwitchPatternCase;
    assertResolvedNodeText(node, r'''
SwitchPatternCase
  keyword: case
  guardedPattern: GuardedPattern
    pattern: LogicalAndPattern
      leftOperand: DeclaredVariablePattern
        keyword: var
        name: a
        declaredFragment: isPublic a@44
          element: hasImplicitType isPublic
            type: int
        matchedValueType: int
      operator: &&
      rightOperand: DeclaredVariablePattern
        keyword: var
        name: a
        declaredFragment: isPublic a@53
          element: hasImplicitType isPublic
            type: int
        matchedValueType: int
      matchedValueType: int
  colon: :
  statements
    ExpressionStatement
      expression2: SimpleIdentifier
        token: a
        element: a@44
        staticType: int
      semicolon: ;
''');
  }

  test_variableDeclaration() async {
    var result = await resolveTestCodeWithDiagnostics(r'''
void f() {
  var [a, a] = [0, 1];
//     ^
// [context 1] The first definition of this name.
//        ^
// [diag.duplicateVariablePattern][context 1] The variable 'a' is already defined in this pattern.
  a;
}
''');

    var node = result.findNode.singleBlock;
    assertResolvedNodeText(node, r'''
Block
  leftBracket: {
  statements
    PatternVariableDeclarationStatement
      declaration: PatternVariableDeclaration
        keyword: var
        pattern: ListPattern
          leftBracket: [
          elements
            DeclaredVariablePattern
              name: a
              declaredFragment: isPublic a@18
                element: hasImplicitType isPublic
                  type: int
              matchedValueType: int
            DeclaredVariablePattern
              name: a
              declaredFragment: isPublic a@21
                element: hasImplicitType isPublic
                  type: int
              matchedValueType: int
          rightBracket: ]
          matchedValueType: List<int>
          requiredType: List<int>
        equals: =
        expression2: ListLiteral
          leftBracket: [
          elements2
            IntegerLiteral
              literal: 0
              staticType: int
            IntegerLiteral
              literal: 1
              staticType: int
          rightBracket: ]
          staticType: List<int>
        patternTypeSchema: List<_>
      semicolon: ;
    ExpressionStatement
      expression2: SimpleIdentifier
        token: a
        element: a@18
        staticType: int
      semicolon: ;
  rightBracket: }
''');
  }
}