Open Radar

 
Summary:
In the Xcode Data Model Editor, inserting certain invalid data into the predicate editor of a fetched property/fetch request can make a predicate uneditable.

Steps to Reproduce:
1. Open Xcode's data model editor
2. Create an entity
3. Create an attribute in the entity. I named it "xyz".
4. Set the type of the attribute to something other than 'Undefined'
5. Create fetched property
6. [!] Set the destination entity of the fetched property to the same entity (it doesn't really matter which entity, so long as it has typed attributes, etc)
7. Click 'Edit Predicate'. The first row should be: someAttribute = [ text field ]
8. Right-click in the "magic space" between the text field and the minus button. Select "Variable" in the context menu
9. Type something invalid. For instance '$foo'. Click OK
10. Now click [Edit Predicate] again

Expected Results:
The edit predicate sheet should show, allowing me to fix my invalid variable.

Actual Results:
An error sheet pops up. 'Error in Predicate Format: Unable to parse the format string "xyz == $foo"'.

In order to edit the predicate, the fetched property must be recreated.

Regression:
Tested in Xcode 3.2.1 (IDE build 1613.0)
Mac OS X 10.6.2