- fixed issue where some custom asset files are returned multiple times (in...

- fixed issue where some custom asset files are returned multiple times (in the same list) by the api

src/ClientServer/Controllers/Core/Exercises/DoExerciseController.cs

@@ -3375,8 +3375,6 @@ namespace ClientServer.Controllers.Core.Exercises
 
             var allFileReferencesForFrontend = new List<FilePreviewFromBackend>();
 
-            customTestFileReferences =
-                customTestFileReferences.DistinctBy(p => p.FileReferenceUserFileAssetId).ToList();
 
             foreach (var fileReference in customTestFileReferences)
             {
@@ -3389,8 +3387,6 @@ namespace ClientServer.Controllers.Core.Exercises
                 });
             }
 
-            customProjectDescriptionFileReferences =
-                customProjectDescriptionFileReferences.DistinctBy(p => p.FileReferenceUserFileAssetId).ToList();
 
             foreach (var fileReference in customProjectDescriptionFileReferences)
             {
@@ -3403,9 +3399,6 @@ namespace ClientServer.Controllers.Core.Exercises
                 });
             }
 
-            customProjectCustomTestFileReferences =
-                customProjectCustomTestFileReferences.DistinctBy(p => p.FileReferenceUserFileAssetId).ToList();
-
             foreach (var fileReference in customProjectCustomTestFileReferences)
             {
                 allFileReferencesForFrontend.Add(new FilePreviewFromBackend()
@@ -3417,6 +3410,11 @@ namespace ClientServer.Controllers.Core.Exercises
                 });
             }
 
+            //we do distinct on the whole list because user file can be used as markdown asset and test asset...
+            //also a test asset can be used in multiple tests... so it's easier to do this on the whole list
+            allFileReferencesForFrontend = allFileReferencesForFrontend
+                .DistinctBy(p => p.Id)
+                .ToList();
 
             await
                 Response.WriteAsync(