Fix T87688: Crash entering valid text into number field

When the user entered a driver expression like `#frame` into a number
field, Blender would crash sometime after. This is because
e1a9ba94c599 did not handle this case properly and ignored the fact
that the user can enter text into the field.

The fix makes sure that we only cancel if the value is a *number* equal
to the previous value in the field.

Note that this could also be handled by `ui_but_string_set` which would
be a bit nicer potentially. However, I was unable to find a clean way of
passing `data->startvalue` into that function. `uiHandleButtonData` is
only known locally inside `interface_handlers.c`.

Reviewed By: Severin

Maniphest Tasks: T87688

Differential Revision: https://developer.blender.org/D11049

1 files changed, 7 insertions, 6 deletions

diff --git a/source/blender/editors/interface/interface_handlers.c b/source/blender/editors/interface/interface_handlers.c
index 4cbf5fca49a..4931b35ca75 100644
--- a/source/blender/editors/interface/interface_handlers.c
+++ b/source/blender/editors/interface/interface_handlers.c
@@ -1114,6 +1114,13 @@ static void ui_apply_but_TAB(bContext *C, uiBut *but, uiHandleButtonData *data)
 static void ui_apply_but_NUM(bContext *C, uiBut *but, uiHandleButtonData *data)
 {
   if (data->str) {
+    double value;
+    /* Check if the string value is a number and cancel if it's equal to the startvalue. */
+    if (ui_but_string_eval_number(C, but, data->str, &value) && (value == data->startvalue)) {
+      data->cancel = true;
+      return;
+    }
+    
     if (ui_but_string_set(C, but, data->str)) {
       data->value = ui_but_value_get(but);
     }
@@ -1121,12 +1128,6 @@ static void ui_apply_but_NUM(bContext *C, uiBut *but, uiHandleButtonData *data)
       data->cancel = true;
       return;
     }
-
-    /* If the value entered is the exact same, do not trigger an update. */
-    if (data->value == data->startvalue) {
-      data->cancel = true;
-      return;
-    }
   }
   else {
     ui_but_value_set(but, data->value);