bpo-36096: IDLE: Refactor class variables in colorizer (GH-12002)

Lib/idlelib/colorizer.py

@@ -55,26 +55,35 @@ def color_config(text):
 class ColorDelegator(Delegator):
     """Delegator for syntax highlighting (text coloring).
 
-    Class variables:
-        after_id: Identifier for scheduled after event.
+    Instance variables:
+        delegate: Delegator below this one in the stack, meaning the
+                one this one delegates to.
+
+        Used to track state:
+        after_id: Identifier for scheduled after event, which is a
+                timer for colorizing the text.
         allow_colorizing: Boolean toggle for applying colorizing.
         colorizing: Boolean flag when colorizing is in process.
         stop_colorizing: Boolean flag to end an active colorizing
                 process.
         close_when_done: Widget to destroy after colorizing process
                 completes (doesn't seem to be used by IDLE).
-
-    Instance variables:
-        delegate: Delegator below this one in the stack, meaning the
-                one this one delegates to.
     """
 
     def __init__(self):
         Delegator.__init__(self)
+        self.init_state()
         self.prog = prog
         self.idprog = idprog
         self.LoadTagDefs()
 
+    def init_state(self):
+        "Initialize variables that track colorizing state."
+        self.after_id = None
+        self.allow_colorizing = True
+        self.stop_colorizing = False
+        self.colorizing = False
+
     def setdelegate(self, delegate):
         """Set the delegate for this instance.
 
@@ -134,11 +143,6 @@ class ColorDelegator(Delegator):
         self.delegate.delete(index1, index2)
         self.notify_range(index1)
 
-    after_id = None
-    allow_colorizing = True
-    stop_colorizing = False
-    colorizing = False
-
     def notify_range(self, index1, index2=None):
         "Mark text changes for processing and restart colorizing, if active."
         self.tag_add("TODO", index1, index2)