UI: Edit Menu - Undo History List and Operator Polling

Enable and Disable Edit Menu items based on whether those actions are currently applicable.

https://developer.blender.org/D4846

Reviewed by Brecht Van Lommel

1 files changed, 31 insertions, 3 deletions

diff --git a/source/blender/editors/undo/ed_undo.c b/source/blender/editors/undo/ed_undo.c
index 9770b52158a..8e190ed9c73 100644
--- a/source/blender/editors/undo/ed_undo.c
+++ b/source/blender/editors/undo/ed_undo.c
@@ -464,6 +464,15 @@ static bool ed_undo_redo_poll(bContext *C)
           WM_operator_check_ui_enabled(C, last_op->type->name));
 }
 
+static bool ed_undo_poll(bContext *C)
+{
+  if (!ed_undo_is_init_and_screenactive_poll(C)) {
+    return false;
+  }
+  UndoStack *undo_stack = CTX_wm_manager(C)->undo_stack;
+  return (undo_stack->step_active != NULL) && (undo_stack->step_active->prev != NULL);
+}
+
 void ED_OT_undo(wmOperatorType *ot)
 {
   /* identifiers */
@@ -473,7 +482,7 @@ void ED_OT_undo(wmOperatorType *ot)
 
   /* api callbacks */
   ot->exec = ed_undo_exec;
-  ot->poll = ed_undo_is_init_and_screenactive_poll;
+  ot->poll = ed_undo_poll;
 }
 
 void ED_OT_undo_push(wmOperatorType *ot)
@@ -498,6 +507,15 @@ void ED_OT_undo_push(wmOperatorType *ot)
                  "");
 }
 
+static bool ed_redo_poll(bContext *C)
+{
+  if (!ed_undo_is_init_and_screenactive_poll(C)) {
+    return false;
+  }
+  UndoStack *undo_stack = CTX_wm_manager(C)->undo_stack;
+  return (undo_stack->step_active != NULL) && (undo_stack->step_active->next != NULL);
+}
+
 void ED_OT_redo(wmOperatorType *ot)
 {
   /* identifiers */
@@ -507,7 +525,7 @@ void ED_OT_redo(wmOperatorType *ot)
 
   /* api callbacks */
   ot->exec = ed_redo_exec;
-  ot->poll = ed_undo_is_init_and_screenactive_poll;
+  ot->poll = ed_redo_poll;
 }
 
 void ED_OT_undo_redo(wmOperatorType *ot)
@@ -697,6 +715,16 @@ static int undo_history_exec(bContext *C, wmOperator *op)
   return OPERATOR_CANCELLED;
 }
 
+static bool undo_history_poll(bContext *C)
+{
+  if (!ed_undo_is_init_and_screenactive_poll(C)) {
+    return false;
+  }
+  UndoStack *undo_stack = CTX_wm_manager(C)->undo_stack;
+  /* More than just original state entry. */
+  return BLI_listbase_count_at_most(&undo_stack->steps, 2) > 1;
+}
+
 void ED_OT_undo_history(wmOperatorType *ot)
 {
   /* identifiers */
@@ -707,7 +735,7 @@ void ED_OT_undo_history(wmOperatorType *ot)
   /* api callbacks */
   ot->invoke = undo_history_invoke;
   ot->exec = undo_history_exec;
-  ot->poll = ed_undo_is_init_and_screenactive_poll;
+  ot->poll = undo_history_poll;
 
   RNA_def_int(ot->srna, "item", 0, 0, INT_MAX, "Item", "", 0, INT_MAX);
 }