Fix platform case sensitivity issue with CsWin32Generator tool (#1499)

* Add regression test for case sensitivity.

* Fix case sensitivity issue with platform.

Author: jevansaks

src/CsWin32Generator/Program.cs

@@ -388,13 +388,23 @@ private GeneratorOptions LoadGeneratorOptions(FileInfo? nativeMethodsJson)
             }
         }
 
-        Platform compilationPlatform = platform switch
+        Platform compilationPlatform = Platform.AnyCpu;
+        if (platform.Equals("x86", StringComparison.OrdinalIgnoreCase))
         {
-            "x86" => Platform.X86,
-            "x64" => Platform.X64,
-            "arm64" => Platform.Arm64,
-            _ => Platform.AnyCpu,
-        };
+            compilationPlatform = Platform.X86;
+        }
+        else if (platform.Equals("x64", StringComparison.OrdinalIgnoreCase))
+        {
+            compilationPlatform = Platform.X64;
+        }
+        else if (platform.Equals("arm64", StringComparison.OrdinalIgnoreCase))
+        {
+            compilationPlatform = Platform.Arm64;
+        }
+        else if (platform.Equals("AnyCPU", StringComparison.OrdinalIgnoreCase))
+        {
+            compilationPlatform = Platform.AnyCpu;
+        }
 
         var compilationOptions = new CSharpCompilationOptions(
             outputKind: OutputKind.DynamicallyLinkedLibrary,

test/CsWin32Generator.Tests/CsWin32GeneratorTests.cs

@@ -88,6 +88,18 @@ public async Task TestGenerateSomethingInWin32System()
         await this.InvokeGeneratorAndCompileFromFact();
     }
 
+    [Theory]
+    [InlineData("x64")]
+    [InlineData("X64")]
+    [InlineData("arm64")]
+    [InlineData("ARM64")]
+    public async Task TestPlatformCaseSensitivity(string platform)
+    {
+        this.platform = platform;
+        this.nativeMethods.Add("SetWindowLongPtr");
+        await this.InvokeGeneratorAndCompile();
+    }
+
     [Theory]
     [InlineData("IMFMediaKeySession", "get_KeySystem", "winmdroot.Foundation.BSTR* keySystem")]
     [InlineData("AddPrinterW", "AddPrinter", "winmdroot.Foundation.PWSTR pName, uint Level, Span<byte> pPrinter")]

test/CsWin32Generator.Tests/CsWin32GeneratorTestsBase.cs

@@ -30,6 +30,7 @@ public partial class CsWin32GeneratorTestsBase : GeneratorTestBase
     protected List<string> additionalReferences = new();
     protected string assemblyName = "TestAssembly";
     protected string? keyFile;
+    protected string platform = "x64";
 
     public CsWin32GeneratorTestsBase(ITestOutputHelper logger)
         : base(logger)
@@ -104,7 +105,7 @@ protected async Task InvokeGenerator(string outputPath, string testCase, TestOpt
         args.AddRange(["--native-methods-txt", nativeMethodsTxtPath]);
         args.AddRange(["--metadata-paths", win32winmd]);
         args.AddRange(["--output-path", outputPath]);
-        args.AddRange(["--platform", "x64"]);
+        args.AddRange(["--platform", this.platform]);
         if (this.nativeMethodsJson is string)
         {
             string nativeMethodsJsonPath = Path.Combine(Path.GetDirectoryName(typeof(CsWin32GeneratorTests).Assembly.Location)!, "TestContent", this.nativeMethodsJson);