# HG changeset patch
# User Pierre-Yves David <pierre-yves.david@fb.com>
# Date 1400972885 25200
# Node ID 31be5a6fa71644976fbad8eb71fdec9d0180f772
# Parent  cc33ae50bab30d67d2bf1c219cfe5c64e19602e3
bundle2: introduce a ReadOnlyPartError exception

As we will introduce functions to alter already created parts, we need a proper
exception to raise when code tries to alter a part that cannot be altered anymore.

diff -r cc33ae50bab3 -r 31be5a6fa716 mercurial/bundle2.py
--- a/mercurial/bundle2.py	Fri May 23 16:20:30 2014 -0700
+++ b/mercurial/bundle2.py	Sat May 24 16:08:05 2014 -0700
@@ -174,6 +174,10 @@
     """error raised when no handler is found for a Mandatory part"""
     pass
 
+class ReadOnlyPartError(RuntimeError):
+    """error raised when code tries to alter a part being generated"""
+    pass
+
 parthandlermapping = {}
 
 def parthandler(parttype):