RCS9006UseElementAccessTests.cs

// Copyright (c) Josef Pihrt and Contributors. Licensed under the Apache License, Version 2.0. See License.txt in the project root for license information.

using System.Threading.Tasks;
using Microsoft.CodeAnalysis;
using Roslynator.CodeAnalysis.CSharp;
using Roslynator.Testing.CSharp;
using Xunit;

namespace Roslynator.CSharp.Analysis.Tests
{
    public class RCS9006UseElementAccessTests : AbstractCSharpDiagnosticVerifier<InvocationExpressionAnalyzer, InvocationExpressionCodeFixProvider>
    {
        public override DiagnosticDescriptor Descriptor { get; } = DiagnosticRules.UseElementAccess;

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task Test_SyntaxList_First()
        {
            await VerifyDiagnosticAndFixAsync(@"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list.[|First()|];
    }
}
", @"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list[0];
    }
}
");
        }

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task Test_SyntaxList_First_Multiline()
        {
            await VerifyDiagnosticAndFixAsync(@"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list
            .[|First()|];
    }
}
", @"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list[0];
    }
}
");
        }

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task Test_SyntaxTriviaList_ElementAt()
        {
            await VerifyDiagnosticAndFixAsync(@"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxTriviaList list = default;

        var second = list.[|ElementAt(1)|];
    }
}
", @"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxTriviaList list = default;

        var second = list[1];
    }
}
");
        }

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task TestNoDiagnostic_FirstWithPredicate()
        {
            await VerifyNoDiagnosticAsync(@"
using System.Linq;
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list.First(f => true);
    }
}
");
        }

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task TestNoDiagnostic_NotSyntaxList()
        {
            await VerifyNoDiagnosticAsync(@"
using System.Collections.Generic;
using System.Linq;
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        List<SyntaxNode> list = default;

        var first = list.First();
    }
}
");
        }

        [Fact, Trait(Traits.Analyzer, DiagnosticIdentifiers.UseElementAccess)]
        public async Task TestNoDiagnostic_TrailingTrivia()
        {
            await VerifyNoDiagnosticAsync(@"
using Microsoft.CodeAnalysis;

class C
{
    void M()
    {
        SyntaxList<SyntaxNode> list = default;

        var first = list // x
            .First();
    }
}
");
        }
    }
}