Update TypeCheckOnlyTests to use console output instead of file side effects

Co-authored-by: T-Gro <[email protected]>

Author: Copilot

tests/FSharp.Compiler.ComponentTests/Scripting/TypeCheckOnlyTests.fs

@@ -28,35 +28,21 @@ let x: int = "string"  // Type error
 
 [<Fact>]
 let ``typecheck-only flag prevents execution side effects``() =
-    let testFilePath = System.IO.Path.GetTempFileName()
-    System.IO.File.Delete(testFilePath) // Make sure file doesn't exist initially
-    
-    Fsx $"""
-System.IO.File.WriteAllText("{testFilePath}", "should not be created")
+    Fsx """
+printfn "MyCrazyString"
 let x = 42
 """
     |> withOptions ["--typecheck-only"]
-    |> eval
+    |> runFsi
     |> shouldSucceed
-    
-    // Verify file was not created
-    Assert.False(System.IO.File.Exists(testFilePath), "File should not have been created when using --typecheck-only")
+    |> VerifyNotInOutput "MyCrazyString"
 
 [<Fact>]
 let ``script executes without typecheck-only flag``() =
-    let testFilePath = System.IO.Path.GetTempFileName()
-    System.IO.File.Delete(testFilePath) // Make sure file doesn't exist initially
-    
-    Fsx $"""
-System.IO.File.WriteAllText("{testFilePath}", "file was created")
+    Fsx """
+printfn "MyCrazyString"
 let x = 42
 """
-    |> eval
+    |> runFsi
     |> shouldSucceed
-    
-    // Verify file was created when not using --typecheck-only
-    Assert.True(System.IO.File.Exists(testFilePath), "File should have been created when not using --typecheck-only")
-    
-    // Clean up
-    if System.IO.File.Exists(testFilePath) then
-        System.IO.File.Delete(testFilePath)
+    |> verifyOutput "MyCrazyString"

tests/FSharp.Test.Utilities/Compiler.fs

@@ -1421,6 +1421,18 @@ Actual:
                     failwith $"""Output does not match expected:{Environment.NewLine}{item}{Environment.NewLine}Actual:{Environment.NewLine}{actual}{Environment.NewLine}"""
             cResult
 
+    let verifyNotInOutput (expected: string) (cResult: CompilationResult) : CompilationResult =
+        match getOutput cResult with
+        | None -> cResult
+        | Some actual ->
+            if actual.Contains(expected) then
+                failwith $"""Output should not contain:{Environment.NewLine}{expected}{Environment.NewLine}Actual:{Environment.NewLine}{actual}{Environment.NewLine}"""
+            else
+                cResult
+
+    let VerifyNotInOutput (expected: string) (cResult: CompilationResult) : CompilationResult =
+        verifyNotInOutput expected cResult
+
     type ImportScope = { Kind: ImportDefinitionKind; Name: string }
 
     type PdbVerificationOption =
@@ -1906,6 +1918,13 @@ Actual:
         let withStdOutContains (substring: string) (result: CompilationResult) : CompilationResult =
             checkOutputInOrder "STDOUT" [substring] (fun o -> o.StdOut)  result
 
+        let withStdOutNotContains (substring: string) (result: CompilationResult) : CompilationResult =
+            let checkOutput = fun o -> o.StdOut
+            let output = checkOutput result.Output
+            if output.Contains(substring) then
+                failwith $"""STDOUT should not contain:{Environment.NewLine}{substring}{Environment.NewLine}Actual:{Environment.NewLine}{output}{Environment.NewLine}"""
+            result
+
         let withStdOutContainsAllInOrder (substrings: string list) (result: CompilationResult) : CompilationResult =
             checkOutputInOrder "STDOUT" substrings (fun o -> o.StdOut) result