Changing tokenize (39046) to detect dedent broke tabnanny check (since 1.2a1)

Lib/idlelib/NEWS.txt

@@ -3,6 +3,8 @@ What's New in IDLE 1.2c1?
 
 *Release date: XX-AUG-2006*
 
+- Changing tokenize (39046) to detect dedent broke tabnanny check (since 1.2a1)
+
 - ToggleTab dialog was setting indent to 8 even if cancelled (since 1.2a1).
 
 - When used w/o subprocess, all exceptions were preceded by an error

Lib/idlelib/ScriptBinding.py

@@ -76,6 +76,9 @@ class ScriptBinding:
             self.editwin.gotoline(nag.get_lineno())
             self.errorbox("Tab/space error", indent_message)
             return False
+        except IndentationError:
+            # From tokenize(), let compile() in checksyntax find it again.
+            pass
         return True
 
     def checksyntax(self, filename):