ProxyGenerator/tests/ProxyInterfaceSourceGeneratorTests/ProxyInterfaceSourceGeneratorTest.cs

using CSharp.SourceGenerators.Extensions;
using CSharp.SourceGenerators.Extensions.Models;
using FluentAssertions;
using ProxyInterfaceSourceGenerator;
using ProxyInterfaceSourceGeneratorTests.Source;
using Xunit;

namespace ProxyInterfaceSourceGeneratorTests
{
    public class ProxyInterfaceSourceGeneratorTest
    {
        private bool Write = true;

        private readonly ProxyInterfaceCodeGenerator _sut;

        public ProxyInterfaceSourceGeneratorTest()
        {
            _sut = new ProxyInterfaceCodeGenerator();

            var pp = new PersonProxy(new Person());

            _ = pp.AddHuman(new HumanProxy(new Human()));
        }

        [Fact]
        public void GenerateFiles_ForStruct_Should_Not_GenerateProxyCode()
        {
            // Arrange
            var path = "./Source/IMyStruct.cs";
            var sourceFile = new SourceFile
            {
                Path = path,
                Text = File.ReadAllText(path),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.MyStruct)"
                }
            };

            // Act
            var result = _sut.Execute(new[] { sourceFile });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(1);
        }

        [Fact]
        public void GenerateFiles_ForGenericType_Should_GenerateCorrectFiles()
        {
            // Arrange
            var fileNames = new[]
            {
                "ProxyInterfaceSourceGeneratorTests.Source.IGeneric.g.cs",
                "ProxyInterfaceSourceGeneratorTests.Source.Generic_T__1Proxy.g.cs"
            };

            var path = "./Source/IGeneric.cs";
            var sourceFile = new SourceFile
            {
                Path = path,
                Text = File.ReadAllText(path),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.Generic<>)"
                }
            };

            // Act
            var result = _sut.Execute(new[]
            {
                sourceFile
            });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(fileNames.Length + 1);

            foreach (var fileName in fileNames.Select((fileName, index) => new { fileName, index }))
            {
                var builder = result.Files[fileName.index + 1]; // +1 means skip the attribute
                builder.Path.Should().EndWith(fileName.fileName);

                if (Write) File.WriteAllText($"../../../Destination/{fileName.fileName}", builder.Text);
                builder.Text.Should().Be(File.ReadAllText($"../../../Destination/{fileName.fileName}"));
            }
        }

        [Fact]
        public void GenerateFiles_When_NoNamespace_Should_GenerateCorrectFiles()
        {
            // Arrange
            var fileNames = new[]
            {
                "INoNamespace.g.cs",
                "NoNamespaceProxy.g.cs"
            };

            var path = "./Source/INoNamespace.cs";
            var sourceFile = new SourceFile
            {
                Path = path,
                Text = File.ReadAllText(path),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.NoNamespace)"
                }
            };

            // Act
            var result = _sut.Execute(new[]
            {
                sourceFile
            });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(fileNames.Length + 1);

            foreach (var fileName in fileNames.Select((fileName, index) => new { fileName, index }))
            {
                var builder = result.Files[fileName.index + 1]; // +1 means skip the attribute
                builder.Path.Should().EndWith(fileName.fileName);

                if (Write) File.WriteAllText($"../../../Destination/{fileName.fileName}", builder.Text);
                builder.Text.Should().Be(File.ReadAllText($"../../../Destination/{fileName.fileName}"));
            }
        }

        [Fact]
        public void GenerateFiles_When_MixedVisibility_Should_GenerateCorrectFiles()
        {
            // Arrange
            var fileNames = new[]
            {
                "ProxyInterfaceSourceGeneratorTests.Source.IMixedVisibility.g.cs",
                "ProxyInterfaceSourceGeneratorTests.Source.MixedVisibilityProxy.g.cs"
            };

            var path = "./Source/IMixedVisibility.cs";
            var sourceFile = new SourceFile
            {
                Path = path,
                Text = File.ReadAllText(path),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.MixedVisibility)"
                }
            };

            // Act
            var result = _sut.Execute(new[]
            {
                sourceFile
            });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(fileNames.Length + 1);

            foreach (var fileName in fileNames.Select((fileName, index) => new { fileName, index }))
            {
                var builder = result.Files[fileName.index + 1]; // +1 means skip the attribute
                builder.Path.Should().EndWith(fileName.fileName);

                if (Write) File.WriteAllText($"../../../Destination/{fileName.fileName}", builder.Text);
                builder.Text.Should().Be(File.ReadAllText($"../../../Destination/{fileName.fileName}"));
            }
        }

        [Fact]
        public void GenerateFiles_ForSingleClass_Should_GenerateCorrectFiles()
        {
            // Arrange
            var attributeFilename = "ProxyInterfaceGenerator.ProxyAttribute.g.cs";
            var interfaceFilename = "ProxyInterfaceSourceGeneratorTests.Source.IPersonExtends.g.cs";
            var proxyClassFilename = "ProxyInterfaceSourceGeneratorTests.Source.PersonExtendsProxy.g.cs";

            var path = "./Source/IPersonExtends.cs";
            var sourceFile = new SourceFile
            {
                Path = path,
                Text = File.ReadAllText(path),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = new[] { "typeof(ProxyInterfaceSourceGeneratorTests.Source.PersonExtends)", "true" }
                }
            };

            // Act
            var result = _sut.Execute(new[] { sourceFile });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(3);

            // Assert attribute
            var attribute = result.Files[0].SyntaxTree;
            attribute.FilePath.Should().EndWith(attributeFilename);

            // Assert interface
            var @interface = result.Files[1].SyntaxTree;
            @interface.FilePath.Should().EndWith(interfaceFilename);

            var interfaceCode = @interface.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{interfaceFilename}", interfaceCode);
            interfaceCode.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{interfaceFilename}"));

            // Assert Proxy
            var proxyClass = result.Files[2].SyntaxTree;
            proxyClass.FilePath.Should().EndWith(proxyClassFilename);

            var proxyCode = proxyClass.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{proxyClassFilename}", proxyCode);
            proxyCode.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{proxyClassFilename}"));
        }

        [Fact]
        public void GenerateFiles_ForTwoClasses_Should_GenerateCorrectFiles()
        {
            // Arrange
            var attributeFilename = "ProxyInterfaceGenerator.ProxyAttribute.g.cs";
            var interfaceHumanFilename = "ProxyInterfaceSourceGeneratorTests.Source.IHuman.g.cs";
            var proxyClassHumanFilename = "ProxyInterfaceSourceGeneratorTests.Source.HumanProxy.g.cs";
            var interfacePersonFilename = "ProxyInterfaceSourceGeneratorTests.Source.IPerson.g.cs";
            var proxyClassPersonFilename = "ProxyInterfaceSourceGeneratorTests.Source.PersonProxy.g.cs";

            var pathPerson = "./Source/IPerson.cs";
            var sourceFilePerson = new SourceFile
            {
                Path = pathPerson,
                Text = File.ReadAllText(pathPerson),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.Person)"
                }
            };

            var pathHuman = "./Source/IHuman.cs";
            var sourceFileHuman = new SourceFile
            {
                Path = pathHuman,
                Text = File.ReadAllText(pathHuman),
                AttributeToAddToInterface = new ExtraAttribute
                {
                    Name = "ProxyInterfaceGenerator.Proxy",
                    ArgumentList = "typeof(ProxyInterfaceSourceGeneratorTests.Source.Human)"
                }
            };

            // Act
            var result = _sut.Execute(new[] { sourceFileHuman, sourceFilePerson });

            // Assert
            result.Valid.Should().BeTrue();
            result.Files.Should().HaveCount(5);

            // Assert attribute
            var attribute = result.Files[0].SyntaxTree;
            attribute.FilePath.Should().EndWith(attributeFilename);


            // Assert interface Human
            var interfaceHuman = result.Files[1].SyntaxTree;
            interfaceHuman.FilePath.Should().EndWith(interfaceHumanFilename);

            var interfaceCodeHuman = interfaceHuman.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{interfaceHumanFilename}", interfaceCodeHuman);
            interfaceCodeHuman.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{interfaceHumanFilename}"));


            // Assert interface Person
            var interfacePerson = result.Files[2].SyntaxTree;
            interfacePerson.FilePath.Should().EndWith(interfacePersonFilename);

            var interfaceCodePerson = interfacePerson.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{interfacePersonFilename}", interfaceCodePerson);
            interfaceCodePerson.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{interfacePersonFilename}"));


            // Assert Proxy Human
            var proxyClassHuman = result.Files[3].SyntaxTree;
            proxyClassHuman.FilePath.Should().EndWith(proxyClassHumanFilename);

            var proxyCodeHuman = proxyClassHuman.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{proxyClassHumanFilename}", proxyCodeHuman);
            proxyCodeHuman.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{proxyClassHumanFilename}"));


            // Assert Proxy Person
            var proxyClassPerson = result.Files[4].SyntaxTree;
            proxyClassPerson.FilePath.Should().EndWith(proxyClassPersonFilename);

            var proxyCode = proxyClassPerson.ToString();
            if (Write) File.WriteAllText($"../../../Destination/{proxyClassPersonFilename}", proxyCode);
            proxyCode.Should().NotBeNullOrEmpty().And.Be(File.ReadAllText($"../../../Destination/{proxyClassPersonFilename}"));
        }

        
    }
}