CSharpAsAndMemberAccessTests.cs

// Licensed to the .NET Foundation under one or more agreements.
// The .NET Foundation licenses this file to you under the MIT license.
// See the LICENSE file in the project root for more information.
 
using System;
using System.Threading.Tasks;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.UsePatternMatching;
using Microsoft.CodeAnalysis.Editor.UnitTests.CodeActions;
using Microsoft.CodeAnalysis.Test.Utilities;
using Roslyn.Test.Utilities;
using Xunit;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.UsePatternMatching;
 
using VerifyCS = CSharpCodeFixVerifier<
    CSharpAsAndMemberAccessDiagnosticAnalyzer,
    CSharpAsAndMemberAccessCodeFixProvider>;
 
[Trait(Traits.Feature, Traits.Features.CodeActionsUsePatternMatchingForAsAndMemberAccess)]
public partial class CSharpAsAndMemberAccessTests
{
    [Fact]
    public async Task TestCoreCase()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length == 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: 0 })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotInCSharp7()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length == 0)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp7,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotWithNonConstant()
    {
        var test = """
            class C
            {
                void M(object o, int length)
                {
                    if ((o as string)?.Length == length)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp7,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotWithoutTest()
    {
        var test = """
            class C
            {
                void M(object o, int length)
                {
                    var v = (o as string)?.Length;
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp7,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotWithNonMemberBinding1()
    {
        var test = """
            class C
            {
                C[] X;
                int Length;
 
                void M(object o, int length)
                {
                    if ((o as C)?.X[0].Length == 0)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp7,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsConstant_CSharp8()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length != 0)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp8,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsConstant_CSharp9()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length != 0)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ValueType_CSharp8()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp8,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ValueType_CSharp9()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ValueType2_CSharp9()
    {
        var test = """
            class C
            {
                C X;
                int Length;
 
                void M(object o)
                {
                    if ((o as C)?.X.Length != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ReferenceType_CSharp8()
    {
        var test = """
            class C
            {
                string X;
 
                void M(object o)
                {
                    if ((o as C)?.X != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp8,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ReferenceType_CSharp9()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    string X;
                
                    void M(object o)
                    {
                        if (([|o as C|])?.X != null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    string X;
 
                    void M(object o)
                    {
                        if (o is C { X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_ReferenceType_CSharp10()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    C Y;
                    string X;
                
                    void M(object o)
                    {
                        if (([|o as C|])?.Y.X != null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    C Y;
                    string X;
 
                    void M(object o)
                    {
                        if (o is C { Y.X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_NullableType_CSharp8()
    {
        var test = """
            class C
            {
                int? X;
 
                void M(object o)
                {
                    if ((o as C)?.X != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp8,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_NullableType2_CSharp8()
    {
        var test = """
            class C
            {
                int? X;
 
                void M(object o)
                {
                    if ((o as C)?.X != null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp8,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestNotEqualsNull_NullableType_CSharp10()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    C Y;
                    int? X;
                
                    void M(object o)
                    {
                        if (([|o as C|])?.Y.X != null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    C Y;
                    int? X;
 
                    void M(object o)
                    {
                        if (o is C { Y.X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestGreaterThan()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length > 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: > 0 })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestGreaterThanEquals()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length >= 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: >= 0 })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestLessThan()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    int Goo;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.Goo < 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    int Goo;
 
                    void M(object o)
                    {
                        if (o is C { Goo: < 0 })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestLessThanEquals()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length <= 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: <= 0 })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsConstantPattern1()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length is 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: 0 })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotConstantPattern()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length is not 0)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNullPattern()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length is null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_ValueType()
    {
        var test = """
            class C
            {
                void M(object o)
                {
                    if ((o as string)?.Length is not null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_ValueType2()
    {
        var test = """
            class C
            {
                C X;
                int Length;
 
                void M(object o)
                {
                    if ((o as C)?.X.Length is not null)
                    {
                    }
                }
            }
            """;
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_ReferenceType()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    string X;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.X is not null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    string X;
 
                    void M(object o)
                    {
                        if (o is C { X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_ReferenceType_CSharp10()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    C Y;
                    string X;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.Y.X is not null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    C Y;
                    string X;
 
                    void M(object o)
                    {
                        if (o is C { Y.X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_NullableValueType()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    int? X;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.X is not null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    int? X;
 
                    void M(object o)
                    {
                        if (o is C { X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestIsNotNullPattern_NullableValueType_CSharp10()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    int? X;
                    C Y;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.Y.X is not null)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    int? X;
                    C Y;
 
                    void M(object o)
                    {
                        if (o is C { Y.X: not null })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestMemberAccess1_CSharp9()
    {
        var test = """
            class C
            {
                C X;
                int Length;
 
                void M(object o)
                {
                    if ((o as C)?.X.Length == 0)
                    {
                    }
                }
            }
            """;
 
        await new VerifyCS.Test
        {
            TestCode = test,
            FixedCode = test,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestMemberAccess1_CSharp10()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    C X;
                    int Length;
 
                    void M(object o)
                    {
                        if (([|o as C|])?.X.Length == 0)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    C X;
                    int Length;
 
                    void M(object o)
                    {
                        if (o is C { X.Length: 0 })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp10,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestParenthesizedParent()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if ((([|o as string|])?.Length == 0) || true)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: 0 } || true)
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact]
    public async Task TestBinaryParent()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                class C
                {
                    void M(object o)
                    {
                        if (([|o as string|])?.Length == 0 && true)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                class C
                {
                    void M(object o)
                    {
                        if (o is string { Length: 0 } && true)
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsTypePattern()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (([|o as Type|])?.Name is string s)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (o is Type { Name: string s })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsNotTypePattern()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if ((o as Type)?.Name is not string s)
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsVarPattern()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (([|o as Type|])?.Name is var s)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (o is Type { Name: var s })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsNotVarPattern()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if ({|CS8518:(o as Type)?.Name is not var s|})
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsRecursivePattern1()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (([|o as Type|])?.Name is { })
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (o is Type { Name: { } })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsRecursivePattern2()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (([|o as Type|])?.Name is { } s)
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (o is Type { Name: { } s })
                        {
                        }
                    }
                }
                """,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsNotRecursivePattern1()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (([|o as Type|])?.Name is not { })
                        {
                        }
                    }
                }
                """,
            FixedCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if (o is Type { Name: not { } })
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/67010")]
    public async Task TestIsNotRecursivePattern2()
    {
        await new VerifyCS.Test
        {
            TestCode = """
                using System;
                class C
                {
                    void M(object o)
                    {
                        if ((o as Type)?.Name is not { } s)
                        {
                        }
                    }
                }
                """,
            LanguageVersion = LanguageVersion.CSharp9,
        }.RunAsync();
    }
}
File: src\Analyzers\CSharp\Tests\UsePatternMatching\CSharpAsAndMemberAccessTests.cs	Web Access
Project: src\src\CodeStyle\CSharp\Tests\Microsoft.CodeAnalysis.CSharp.CodeStyle.UnitTests.csproj (Microsoft.CodeAnalysis.CSharp.CodeStyle.UnitTests)