File: src\Analyzers\CSharp\Tests\UseConditionalExpression\UseConditionalExpressionForReturnTests.cs
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Project: src\src\CodeStyle\CSharp\Tests\Microsoft.CodeAnalysis.CSharp.CodeStyle.UnitTests.csproj (Microsoft.CodeAnalysis.CSharp.CodeStyle.UnitTests)
// 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.Threading.Tasks;
using Microsoft.CodeAnalysis.CodeFixes;
using Microsoft.CodeAnalysis.CSharp;
using Microsoft.CodeAnalysis.CSharp.UseConditionalExpression;
using Microsoft.CodeAnalysis.Diagnostics;
using Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.Diagnostics;
using Microsoft.CodeAnalysis.Test.Utilities;
using Roslyn.Test.Utilities;
using Xunit;
using Xunit.Abstractions;
 
namespace Microsoft.CodeAnalysis.Editor.CSharp.UnitTests.UseConditionalExpression;
 
[Trait(Traits.Feature, Traits.Features.CodeActionsUseConditionalExpression)]
public sealed class UseConditionalExpressionForReturnTests(ITestOutputHelper logger)
    : AbstractCSharpDiagnosticProviderBasedUserDiagnosticTest_NoEditor(logger)
{
    private static readonly ParseOptions CSharp8 = CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp8);
    private static readonly ParseOptions CSharp9 = CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp9);
 
    internal override (DiagnosticAnalyzer, CodeFixProvider) CreateDiagnosticProviderAndFixer(Workspace workspace)
        => (new CSharpUseConditionalExpressionForReturnDiagnosticAnalyzer(),
            new CSharpUseConditionalExpressionForReturnCodeFixProvider());
 
    [Fact]
    public async Task TestOnSimpleReturn()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestOnSimpleReturn_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true ? throw new System.Exception() : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestOnSimpleReturn_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true ? 0 : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestNotWithTwoThrows()
    {
        await TestMissingAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestNotOnSimpleReturn_Throw1_CSharp6()
    {
        await TestMissingAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """, parameters: new TestParameters(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(LanguageVersion.CSharp6)));
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestNotWithSimpleThrow()
    {
        await TestMissingAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw;
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestOnSimpleReturnNoBlocks()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                        return 0;
                    else
                        return 1;
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestOnSimpleReturnNoBlocks_NotInBlock()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    if (true)
                        [||]if (true)
                            return 0;
                        else
                            return 1;
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    if (true)
                        return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMissingReturnValue1()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
                    else
                    {
                        return;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestMissingReturnValue1_Throw()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return;
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMissingReturnValue2()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return;
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestMissingReturnValue2_Throw()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMissingReturnValue3()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return;
                    }
                    else
                    {
                        return;
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestWithNoElseBlockButFollowingReturn()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
 
                    return 1;
                }
            }
            """,
            """
            class C
            {
                void M()
                {
                    return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestWithNoElseBlockButFollowingReturn_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
 
                    return 1;
                }
            }
            """,
            """
            class C
            {
                void M()
                {
                    return true ? throw new System.Exception() : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestWithNoElseBlockButFollowingReturn_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
 
                    throw new System.Exception();
                }
            }
            """,
            """
            class C
            {
                void M()
                {
                    return true ? 0 : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMissingWithoutElse()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestMissingWithoutElse_Throw()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70750")]
    public async Task TestMissingWithChecked()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x < 0)
                    {
                        throw new System.Exception();
                    }
                    checked
                    {
                        return x - y;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithCheckedInIf()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (checked(x == y))
                    {
                        return 0;
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return checked(x == y) ? 0 : 1;
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithUncheckedInIf()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (unchecked(x == y))
                    {
                        return 0;
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return unchecked(x == y) ? 0 : 1;
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithCheckedInTrueStatement()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x == y)
                    {
                        return checked(x - y);
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return x == y ? checked(x - y) : 1;
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithUncheckedInTrueStatement()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x == y)
                    {
                        return unchecked(x - y);
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return x == y ? unchecked(x - y) : 1;
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithCheckedInFalseStatement()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x == y)
                    {
                        return 1;
                    }
                    else
                    {
                        return checked(x - y);
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return x == y ? 1 : checked(x - y);
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70748")]
    public async Task TestMissingWithUncheckedInFalseStatement()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x == y)
                    {
                        return 1;
                    }
                    else
                    {
                        return unchecked(x - y);
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    return x == y ? 1 : unchecked(x - y);
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70750")]
    public async Task TestMissingWithUnchecked()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x < 0)
                    {
                        throw new System.Exception();
                    }
                    unchecked
                    {
                        return x - y;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/70750")]
    public async Task TestMissingWithUnsafe()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    int x = 0;
                    int y = 0;
                    [||]if (x < 0)
                    {
                        throw new System.Exception();
                    }
                    unsafe
                    {
                        return x - y;
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestConversion1_CSharp8()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        return "b";
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? "a" : (object)"b";
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact]
    public async Task TestConversion1_CSharp9()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        return "b";
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? "a" : (object)"b";
                }
            }
            """, parseOptions: CSharp9);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestConversion1_Throw1_CSharp8()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return "b";
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? throw new System.Exception() : (object)"b";
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestConversion1_Throw1_CSharp9()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return "b";
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? throw new System.Exception() : (object)"b";
                }
            }
            """, parseOptions: CSharp9);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestConversion1_Throw2_CSharp8()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? (object)"a" : throw new System.Exception();
                }
            }
            """, parseOptions: CSharp8);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestConversion1_Throw2_CSharp9()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                object M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                object M()
                {
                    return true ? (object)"a" : throw new System.Exception();
                }
            }
            """, parseOptions: CSharp9);
    }
 
    [Fact]
    public async Task TestConversion2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? "a" : null;
                }
            }
            """);
    }
 
    [Theory, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    [InlineData(LanguageVersion.CSharp8, "(string)null")]
    [InlineData(LanguageVersion.CSharp9, "null")]
    public async Task TestConversion2_Throw1(LanguageVersion languageVersion, string expectedFalseExpression)
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? throw new System.Exception() : 
            """ + expectedFalseExpression + """
            ;
                }
            }
            """, parameters: new(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(languageVersion)));
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestConversion2_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        return "a";
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? "a" : throw new System.Exception();
                }
            }
            """);
    }
 
    [Theory]
    [InlineData(LanguageVersion.CSharp8, "(string)null")]
    [InlineData(LanguageVersion.CSharp9, "null")]
    public async Task TestConversion3(LanguageVersion languageVersion, string expectedFalseExpression)
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        return null;
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? null : 
            """ + expectedFalseExpression + """
            ;
                }
            }
            """, parameters: new(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(languageVersion)));
    }
 
    [Theory, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    [InlineData(LanguageVersion.CSharp8, "(string)null")]
    [InlineData(LanguageVersion.CSharp9, "null")]
    public async Task TestConversion3_Throw1(LanguageVersion languageVersion, string expectedFalseExpression)
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return null;
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? throw new System.Exception() : 
            """ + expectedFalseExpression + """
            ;
                }
            }
            """, parameters: new(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(languageVersion)));
    }
 
    [Theory, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    [InlineData(LanguageVersion.CSharp8, "(string)null")]
    [InlineData(LanguageVersion.CSharp9, "null")]
    public async Task TestConversion3_Throw2(LanguageVersion languageVersion, string expectedTrue)
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                string M()
                {
                    [||]if (true)
                    {
                        return null;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                string M()
                {
                    return true ? 
            """ + expectedTrue + """
             : throw new System.Exception();
                }
            }
            """, parameters: new(parseOptions: CSharpParseOptions.Default.WithLanguageVersion(languageVersion)));
    }
 
    [Fact]
    public async Task TestKeepTriviaAroundIf()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    // leading
                    [||]if (true)
                    {
                        return 0;
                    }
                    else
                    {
                        return 1;
                    } // trailing
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    // leading
                    return true ? 0 : 1; // trailing
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestFixAll1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    {|FixAllInDocument:if|} (true)
                    {
                        return 0;
                    }
                    else
                    {
                        return 1;
                    }
 
                    if (true)
                    {
                        return 2;
                    }
 
                    return 3;
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true ? 0 : 1;
 
                    return true ? 2 : 3;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMultiLine1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return Foo(
                            1, 2, 3);
                    }
                    else
                    {
                        return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true
                        ? Foo(
                            1, 2, 3)
                        : 1;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMultiLine2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return 0;
                    }
                    else
                    {
                        return Foo(
                            1, 2, 3);
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true
                        ? 0
                        : Foo(
                            1, 2, 3);
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestMultiLine3()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        return Foo(
                            1, 2, 3);
                    }
                    else
                    {
                        return Foo(
                            4, 5, 6);
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    return true
                        ? Foo(
                            1, 2, 3)
                        : Foo(
                            4, 5, 6);
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestElseIfWithBlock()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else [||]if (false)
                    {
                        return 1;
                    }
                    else
                    {
                        return 0;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else
                    {
                        return false ? 1 : 0;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestElseIfWithBlock_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else [||]if (false)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return 0;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else
                    {
                        return false ? throw new System.Exception() : 0;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestElseIfWithBlock_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else [||]if (false)
                    {
                        return 1;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    if (true)
                    {
                    }
                    else
                    {
                        return false ? 1 : throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestElseIfWithoutBlock()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    if (true) return 2;
                    else [||]if (false) return 1;
                    else return 0;
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    if (true) return 2;
                    else return false ? 1 : 0;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestRefReturns1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                ref int M(ref int i, ref int j)
                {
                    [||]if (true)
                    {
                        return ref i;
                    }
                    else
                    {
                        return ref j;
                    }
                }
            }
            """,
            """
            class C
            {
                ref int M(ref int i, ref int j)
                {
                    return ref true ? ref i : ref j;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestRefReturns1_Throw1()
    {
        await TestMissingAsync(
            """
            class C
            {
                ref int M(ref int i, ref int j)
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return ref j;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestRefReturns1_Throw2()
    {
        await TestMissingAsync(
            """
            class C
            {
                ref int M(ref int i, ref int j)
                {
                    [||]if (true)
                    {
                        return ref i;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestOnYieldReturn()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
                    else
                    {
                        yield return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    yield return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    [WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestOnYieldReturn_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        yield return 1;
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    yield return true ? throw new System.Exception() : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    [WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestOnYieldReturn_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                int M()
                {
                    yield return true ? 0 : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestOnYieldReturn_IEnumerableReturnType()
    {
        await TestInRegularAndScript1Async(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<int> M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
                    else
                    {
                        yield return 1;
                    }
                }
            }
            """,
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<int> M()
                {
                    yield return true ? 0 : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestNotOnMixedYields()
    {
        await TestMissingAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        yield break;
                    }
                    else
                    {
                        yield return 1;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    [WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestNotOnMixedYields_Throw1()
    {
        await TestMissingAsync(
            """
            class C
            {
                int M()
                {
                    [||]if (true)
                    {
                        yield break;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestNotOnMixedYields_IEnumerableReturnType()
    {
        await TestMissingAsync(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<int> M()
                {
                    [||]if (true)
                    {
                        yield break;
                    }
                    else
                    {
                        yield return 1;
                    }
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestNotWithNoElseBlockButFollowingYieldReturn()
    {
        await TestMissingAsync(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
 
                    yield return 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    [WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestWithNoElseBlockButFollowingYieldReturn_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        throw new System.Exception();
                    }
 
                    yield return 1;
                }
            }
            """,
 
            """
            class C
            {
                void M()
                {
                    yield return true ? throw new System.Exception() : 1;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    [WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestNotWithNoElseBlockButFollowingYieldReturn_Throw2()
    {
        await TestMissingAsync(
            """
            class C
            {
                void M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
 
                    throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/27960")]
    public async Task TestNotWithNoElseBlockButFollowingYieldReturn_IEnumerableReturnType()
    {
        await TestMissingAsync(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<int> M()
                {
                    [||]if (true)
                    {
                        yield return 0;
                    }
 
                    yield return 1;
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestReturnTrueFalse1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse1_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return false;
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? throw new System.Exception() : false;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse1_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return true;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? true : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestReturnTrueFalse2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return false;
                    }
                    else
                    {
                        return true;
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a != 0;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse2_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        return true;
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? throw new System.Exception() : true;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse2_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return false;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? false : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestReturnTrueFalse3()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return false;
                    }
 
                    return true;
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a != 0;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse3_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        throw new System.Exception();
                    }
 
                    return true;
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? throw new System.Exception() : true;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse3_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            class C
            {
                bool M(int a)
                {
                    [||]if (a == 0)
                    {
                        return false;
                    }
 
                    throw new System.Exception();
                }
            }
            """,
            """
            class C
            {
                bool M(int a)
                {
                    return a == 0 ? false : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact]
    public async Task TestReturnTrueFalse4()
    {
        await TestInRegularAndScript1Async(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    [||]if (a == 0)
                    {
                        yield return false;
                    }
                    else
                    {
                        yield return true;
                    }
                }
            }
            """,
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    yield return a != 0;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse4_Throw1()
    {
        await TestInRegularAndScript1Async(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    [||]if (a == 0)
                    {
                        throw new System.Exception();
                    }
                    else
                    {
                        yield return true;
                    }
                }
            }
            """,
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    yield return a == 0 ? throw new System.Exception() : true;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/43291")]
    public async Task TestReturnTrueFalse4_Throw2()
    {
        await TestInRegularAndScript1Async(
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    [||]if (a == 0)
                    {
                        yield return false;
                    }
                    else
                    {
                        throw new System.Exception();
                    }
                }
            }
            """,
            """
            using System.Collections.Generic;
 
            class C
            {
                IEnumerable<bool> M(int a)
                {
                    yield return a == 0 ? false : throw new System.Exception();
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/36117")]
    public async Task TestMissingWhenCrossingPreprocessorDirective()
    {
        await TestMissingInRegularAndScriptAsync(
            """
            class C
            {
                int M()
                {
                    bool check = true;
            #if true
                    [||]if (check)
                        return 3;
            #endif
                    return 2;
                }
            }
            """);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/39260")]
    public async Task TestTitleWhenSimplifying()
    {
        await TestInRegularAndScriptAsync(
            """
            class C
            {
                void M(string node1, string node2)
                {
                    [|if|] (AreSimilarCore(node1, node2))
                    {
                        return true;
                    }
                    else
                    {
                        return false;
                    }
                }
 
                private bool AreSimilarCore(string node1, string node2)
                {
                    throw new NotImplementedException();
                }
            }
            """,
            """
            class C
            {
                void M(string node1, string node2)
                {
                    return AreSimilarCore(node1, node2);
                }
 
                private bool AreSimilarCore(string node1, string node2)
                {
                    throw new NotImplementedException();
                }
            }
            """, title: AnalyzersResources.Simplify_check);
    }
 
    [Fact, WorkItem("https://github.com/dotnet/roslyn/issues/38879")]
    public async Task TesSuppressionOperator()
    {
        await TestInRegularAndScript1Async("""
            #nullable enable
 
            class Program
            {
                public static string Method(bool empty)
                {
                    [||]if (empty)
                    {
                        return string.Empty;
                    }
 
                    return null!;
                }
            }
            """, """
            #nullable enable
            
            class Program
            {
                public static string Method(bool empty)
                {
                    return empty ? string.Empty : null!;
                }
            }
            """);
    }
}