diff --git a/tests/FSharp.Test.Utilities/Compiler.fs b/tests/FSharp.Test.Utilities/Compiler.fs
index 4e1850dbdc8..18676f5893d 100644
--- a/tests/FSharp.Test.Utilities/Compiler.fs
+++ b/tests/FSharp.Test.Utilities/Compiler.fs
@@ -173,12 +173,12 @@ module rec Compiler =
 
     let withOptions (options: string list) (cUnit: CompilationUnit) : CompilationUnit =
         match cUnit with
-        | FS fs -> FS { fs with Options = options }
+        | FS fs -> FS { fs with Options = fs.Options @ options }
         | _ -> failwith "withOptions is only supported n F#"
 
     let withPreview (cUnit: CompilationUnit) : CompilationUnit =
         match cUnit with
-        | FS fs -> FS { fs with Options = [ "--langversion:preview" ] }
+        | FS fs -> FS { fs with Options = fs.Options @ [ "--langversion:preview" ] }
         | _ -> failwith "withPreview is only supported in F#"
 
     let asLibrary (cUnit: CompilationUnit) : CompilationUnit =