Clean/Rebuild removes old resources cache from obj folder

packages/Avalonia/AvaloniaBuildTasks.targets

@@ -48,8 +48,12 @@
   </PropertyGroup>
 
   <Target Name="_GenerateAvaloniaResourcesDependencyCache" BeforeTargets="GenerateAvaloniaResources">
+    <PropertyGroup>
+      <_AvaloniaResourcesInputsCacheFilePath>$(IntermediateOutputPath)/Avalonia/Resources.Inputs.cache</_AvaloniaResourcesInputsCacheFilePath>
+    </PropertyGroup>
+
     <ItemGroup>
-      <CustomAdditionalGenerateAvaloniaResourcesInputs Include="$(IntermediateOutputPath)/Avalonia/Resources.Inputs.cache" />
+      <CustomAdditionalGenerateAvaloniaResourcesInputs Include="$(_AvaloniaResourcesInputsCacheFilePath)" />
     </ItemGroup>
     
     <Hash ItemsToHash="@(AvaloniaResource);@(AvaloniaXaml);$(MSBuildAllProjects)">
@@ -57,7 +61,11 @@
     </Hash>
 
     <MakeDir Directories="$(IntermediateOutputPath)/Avalonia" />
-    <WriteLinesToFile Overwrite="true" File="$(IntermediateOutputPath)/Avalonia/Resources.Inputs.cache" Lines="$(AvaloniaResourcesDependencyHash)" WriteOnlyWhenDifferent="True" />
+    <WriteLinesToFile Overwrite="true" File="$(_AvaloniaResourcesInputsCacheFilePath)" Lines="$(AvaloniaResourcesDependencyHash)" WriteOnlyWhenDifferent="True" />
+
+    <ItemGroup>
+      <FileWrites Include="$(_AvaloniaResourcesInputsCacheFilePath)" />
+    </ItemGroup>
   </Target>
   
   <Target Name="GenerateAvaloniaResources" 
@@ -68,7 +76,7 @@
           Condition="('@(AvaloniaResource->Count())' &gt; 0) or ('@(AvaloniaXaml->Count())' &gt; 0)"
           >
     <ItemGroup>
-        <AvaloniaResource Include="@(AvaloniaXaml)"/>
+      <AvaloniaResource Include="@(AvaloniaXaml)" />
     </ItemGroup>
     <GenerateAvaloniaResourcesTask
       Condition="'$(_AvaloniaUseExternalMSBuild)' != 'true'"
@@ -76,6 +84,9 @@
       Root="$(MSBuildProjectDirectory)"
       Resources="@(AvaloniaResource)"
       ReportImportance="$(AvaloniaXamlReportImportance)"/>
+    <ItemGroup Condition="'$(_AvaloniaUseExternalMSBuild)' != 'true'">
+      <FileWrites Include="$(AvaloniaResourcesTemporaryFilePath)" />
+    </ItemGroup>
     <Exec 
       Condition="'$(_AvaloniaUseExternalMSBuild)' == 'true'"
       Command="dotnet msbuild /nodereuse:false $(MSBuildProjectFile) /t:GenerateAvaloniaResources /p:_AvaloniaForceInternalMSBuild=true /p:Configuration=$(Configuration) /p:TargetFramework=$(TargetFramework) /p:RuntimeIdentifier=$(RuntimeIdentifier) /p:BuildProjectReferences=false"/>
@@ -103,6 +114,9 @@
       File="$(AvaloniaXamlReferencesTemporaryFilePath)"
       Lines="@(ReferencePathWithRefAssemblies)"
       Overwrite="true" />
+    <ItemGroup Condition="'$(_AvaloniaForceInternalMSBuild)' != 'true'">
+      <FileWrites Include="$(AvaloniaXamlReferencesTemporaryFilePath)" />
+    </ItemGroup>
     <CompileAvaloniaXamlTask
       Condition="'$(_AvaloniaUseExternalMSBuild)' != 'true'"
       AssemblyFile="@(IntermediateAssembly)"
@@ -117,8 +131,9 @@
       DelaySign="$(DelaySign)"
       SkipXamlCompilation="$(_AvaloniaSkipXamlCompilation)"
       DebuggerLaunch="$(AvaloniaXamlIlDebuggerLaunch)"
-      DefaultCompileBindings="$(AvaloniaUseCompiledBindingsByDefault)"
-    />
+      DefaultCompileBindings="$(AvaloniaUseCompiledBindingsByDefault)">
+      <Output TaskParameter="WrittenFilePaths" ItemName="FileWrites" />
+    </CompileAvaloniaXamlTask>
     <Exec
       Condition="'$(_AvaloniaUseExternalMSBuild)' == 'true'"
       Command="dotnet msbuild /nodereuse:false $(MSBuildProjectFile) /t:CompileAvaloniaXaml /p:_AvaloniaForceInternalMSBuild=true /p:Configuration=$(Configuration) /p:TargetFramework=$(TargetFramework) /p:RuntimeIdentifier=$(RuntimeIdentifier) /p:BuildProjectReferences=false"/>

src/Avalonia.Build.Tasks/CompileAvaloniaXamlTask.cs

@@ -1,4 +1,5 @@
 using System;
+using System.Collections.Generic;
 using System.IO;
 using System.Linq;
 using Microsoft.Build.Framework;
@@ -10,9 +11,10 @@ namespace Avalonia.Build.Tasks
         public bool Execute()
         {
             Enum.TryParse(ReportImportance, true, out MessageImportance outputImportance);
+            var writtenFilePaths = new List<string>();
 
-            OutputPath = OutputPath ?? AssemblyFile;
-            RefOutputPath = RefOutputPath ?? RefAssemblyFile;
+            OutputPath ??= AssemblyFile;
+            RefOutputPath ??= RefAssemblyFile;
             var outputPdb = GetPdbPath(OutputPath);
             var input = AssemblyFile;
             var refInput = RefOutputPath;
@@ -21,8 +23,9 @@ namespace Avalonia.Build.Tasks
             if (OriginalCopyPath != null)
             {
                 var originalCopyPathRef = Path.ChangeExtension(OriginalCopyPath, ".ref.dll");
-                
+
                 File.Copy(AssemblyFile, OriginalCopyPath, true);
+                writtenFilePaths.Add(OriginalCopyPath);
                 input = OriginalCopyPath;
                 File.Delete(AssemblyFile);
 
@@ -30,6 +33,7 @@ namespace Avalonia.Build.Tasks
                 {
                     var copyPdb = GetPdbPath(OriginalCopyPath);
                     File.Copy(inputPdb, copyPdb, true);
+                    writtenFilePaths.Add(copyPdb);
                     File.Delete(inputPdb);
                     inputPdb = copyPdb;
                 }
@@ -39,6 +43,7 @@ namespace Avalonia.Build.Tasks
                     // We also copy ref assembly just for case if needed later for testing.
                     // But do not remove the original one, as MSBuild actually complains about it with multi-thread compiling.
                     File.Copy(RefAssemblyFile, originalCopyPathRef, true);
+                    writtenFilePaths.Add(originalCopyPathRef);
                     refInput = originalCopyPathRef;
                 }
             }
@@ -53,13 +58,25 @@ namespace Avalonia.Build.Tasks
                 ProjectDirectory, VerifyIl, DefaultCompileBindings, outputImportance,
                 (SignAssembly && !DelaySign) ? AssemblyOriginatorKeyFile : null, SkipXamlCompilation, DebuggerLaunch);
             if (!res.Success)
+            {
+                WrittenFilePaths = writtenFilePaths.ToArray();
                 return false;
+            }
+
             if (!res.WrittenFile)
             {
                 File.Copy(input, OutputPath, true);
-                if(File.Exists(inputPdb))
+                if (File.Exists(inputPdb))
                     File.Copy(inputPdb, outputPdb, true);
             }
+            else if (!string.IsNullOrWhiteSpace(RefOutputPath) && File.Exists(RefOutputPath))
+                writtenFilePaths.Add(RefOutputPath);
+
+            writtenFilePaths.Add(OutputPath);
+            if (File.Exists(outputPdb))
+                writtenFilePaths.Add(outputPdb);
+
+            WrittenFilePaths = writtenFilePaths.ToArray();
             return true;
         }
 
@@ -103,5 +120,8 @@ namespace Avalonia.Build.Tasks
         public ITaskHost HostObject { get; set; }
 
         public bool DebuggerLaunch { get; set; }
+
+        [Output]
+        public string[] WrittenFilePaths { get; private set; } = Array.Empty<string>();
     }
 }