Mutannot/Program.fs

@@ -121,11 +121,13 @@ let getMutationCases projectPath =
 
 type Arguments =
     | [<MainCommand; ExactlyOnce>] ProjectPath of ProjectPath: string
+    | ValidateOnly
 
     interface IArgParserTemplate with
         member s.Usage =
             match s with
             | ProjectPath _ -> "path/to/project.csproj|fsproj"
+            | ValidateOnly -> "check if the patches apply, but don't run the mutations"
 
 [<EntryPoint>]
 let main argv =
@@ -134,6 +136,7 @@ let main argv =
         |> _.ParseCommandLine(argv)
 
     let projectPath = parsedArguments.GetResult ProjectPath
+    let validateOnly = parsedArguments.Contains ValidateOnly
 
     ensureCleanWorkingDirectory ()
 
@@ -153,10 +156,12 @@ let main argv =
         Console.ResetColor()
         printf "%s\n" mutationCase.Patch
 
+        applyPatch mutationCase.Patch
+
+        if not validateOnly then
             Console.ForegroundColor <- ConsoleColor.Magenta
             printf "Output:\n"
             Console.ResetColor()
-        applyPatch mutationCase.Patch
 
             match runTest projectPath mutationCase.TestName with
             | 0 ->
@@ -171,7 +176,12 @@ let main argv =
         restore ()
 
     Console.ForegroundColor <- ConsoleColor.Green
+
+    if validateOnly then
+        printf "Success: All mutantions valid\n"
+    else
         printf "Success: All mutants killed\n"
+
     Console.ResetColor()
 
     0