Support $(ProjectName).NativeMethods.txt pattern for single-file-app projects (#1550)

* Support $(ProjectName).NativeMethods.txt pattern for single-file-app projects

Author: jevansaks

integration-tests/buildtask-sdk/app/NativeMethods.txt

@@ -1,2 +1 @@
 GetTickCount
-GetForegroundWindow

integration-tests/buildtask-sdk/app/buildtask-sdk.NativeMethods.txt

@@ -0,0 +1,2 @@
+// This file tests that $(ProjectName).NativeMethods.txt is automatically picked up.
+GetForegroundWindow

integration-tests/sdk/Program.cs

@@ -1,7 +1,11 @@
-class Program
+using Windows.Win32.Foundation;
+
+class Program
 {
     static void Main(string[] args)
     {
         Windows.Win32.PInvoke.GetTickCount();
+
+        HWND hwnd = Windows.Win32.PInvoke.GetForegroundWindow();
     }
 }

integration-tests/sdk/sdk.NativeMethods.txt

@@ -0,0 +1 @@
+GetForegroundWindow

src/Microsoft.Windows.CsWin32/SourceGenerator.cs

@@ -185,7 +185,7 @@ public void Execute(GeneratorExecutionContext context)
 
         GeneratorOptions? options;
         AdditionalText? nativeMethodsJsonFile = context.AdditionalFiles
-            .FirstOrDefault(af => string.Equals(Path.GetFileName(af.Path), NativeMethodsJsonAdditionalFileName, StringComparison.OrdinalIgnoreCase));
+            .FirstOrDefault(af => Path.GetFileName(af.Path).EndsWith(NativeMethodsJsonAdditionalFileName, StringComparison.OrdinalIgnoreCase));
         if (nativeMethodsJsonFile is object)
         {
             string optionsJson = nativeMethodsJsonFile.GetText(context.CancellationToken)!.ToString();
@@ -205,7 +205,7 @@ public void Execute(GeneratorExecutionContext context)
         }
 
         IEnumerable<AdditionalText> nativeMethodsTxtFiles = context.AdditionalFiles
-            .Where(af => string.Equals(Path.GetFileName(af.Path), NativeMethodsTxtAdditionalFileName, StringComparison.OrdinalIgnoreCase));
+            .Where(af => Path.GetFileName(af.Path).EndsWith(NativeMethodsTxtAdditionalFileName, StringComparison.OrdinalIgnoreCase));
         if (!nativeMethodsTxtFiles.Any())
         {
             return;

src/Microsoft.Windows.CsWin32/build/Microsoft.Windows.CsWin32.props

@@ -16,6 +16,13 @@
     <AdditionalFiles Include="NativeMethods.txt" Condition="Exists('NativeMethods.txt')">
       <Generator Condition="'$(CsWin32RunAsBuildTask)'=='true'">MSBuild:Compile</Generator>
     </AdditionalFiles>
+    <AdditionalFiles Include="$(ProjectName).NativeMethods.json" Condition="Exists('$(ProjectName).NativeMethods.json')">
+      <!-- Add this metadata to trigger a design-time build to re-run the generator for CsWin32RunAsBuildTask=true scenarios. -->
+      <Generator Condition="'$(CsWin32RunAsBuildTask)'=='true'">MSBuild:Compile</Generator>
+    </AdditionalFiles>
+    <AdditionalFiles Include="$(ProjectName).NativeMethods.txt" Condition="Exists('$(ProjectName).NativeMethods.txt')">
+      <Generator Condition="'$(CsWin32RunAsBuildTask)'=='true'">MSBuild:Compile</Generator>
+    </AdditionalFiles>
   </ItemGroup>
 
   <ItemGroup>

src/Microsoft.Windows.CsWin32/build/Microsoft.Windows.CsWin32.targets

@@ -45,8 +45,8 @@
           Outputs="$(CsWin32GeneratorGeneratedFilesList);@(CsWin32GeneratorPreviousOutputs);$(CsWin32GeneratorSucceededMarker)"
           Condition="'$(CsWin32RunAsBuildTask)'=='true' and '@(ProjectionMetadataWinmd)'!=''">
     <ItemGroup>
-      <CsWin32NativeMethodsTxt Include="%(AdditionalFiles.FullPath)" Condition="'%(FileName)%(Extension)'=='NativeMethods.txt'" />
-      <CsWin32NativeMethodsJson Include="%(AdditionalFiles.FullPath)" Condition="'%(FileName)%(Extension)'=='NativeMethods.json'" />
+      <CsWin32NativeMethodsTxt Include="%(AdditionalFiles.FullPath)" Condition="$([System.String]::new('%(FileName)%(Extension)').EndsWith('NativeMethods.txt'))" />
+      <CsWin32NativeMethodsJson Include="%(AdditionalFiles.FullPath)" Condition="$([System.String]::new('%(FileName)%(Extension)').EndsWith('NativeMethods.json'))" />
     </ItemGroup>
 
     <PropertyGroup>