Set boundary for Console.CursorTop

dsyme · Nov 22, 2014 · 4f94347 · 4f94347
1 parent 25d8ea0
commit 4f94347
Showing 1 changed file with 2 additions and 1 deletion.
diff --git a/src/fsharp/fsi/console.fs b/src/fsharp/fsi/console.fs
@@ -131,7 +131,7 @@ module Utils =
 type Cursor =
     static member ResetTo(top,left) = 
         Utils.guard(fun () -> 
-           Console.CursorTop <- top;
+           Console.CursorTop <- min top (Console.BufferHeight - 1);
            Console.CursorLeft <- left)
     static member Move(inset, delta) =
         let position = Console.CursorTop * (Console.BufferWidth - inset) + (Console.CursorLeft - inset) + delta
@@ -216,6 +216,7 @@ type ReadLineConsole() =
             if currLeft < x.Inset then 
                 if currLeft = 0 then Console.Write (if prompt then x.Prompt2 else String(' ',x.Inset))
                 Utils.guard(fun () -> 
+                    Console.CursorTop <- min Console.CursorTop (Console.BufferHeight - 1);
                     Console.CursorLeft <- x.Inset);
 
         // The caller writes the primary prompt.  If we are reading the 2nd and subsequent lines of the