Fixed Issue #6929 Escape unicode when inspecting a Str

Author: timonkrebs

crates/compiler/builtins/roc/Inspect.roc

@@ -258,8 +258,15 @@ dbgStr = \s ->
     custom \f0 ->
         f0
         |> dbgWrite "\""
-        |> dbgWrite s # TODO: Should we be escaping strings for dbg/logging?
+        |> \f1 -> 
+            # escape invisible unicode characters
+            escapeS = Str.replaceEach s "\u(feff)" "\\u(feff)"
+                |> Str.replaceEach "\u(200b)" "\\u(200b)" 
+                |> Str.replaceEach "\u(200c)" "\\u(200c)"
+                |> Str.replaceEach "\u(200d)" "\\u(200d)"
+            dbgWrite f1 escapeS
         |> dbgWrite "\""
+        
 
 dbgOpaque : * -> Inspector DbgFormatter
 dbgOpaque = \_ ->