# HG changeset patch
# User Mateusz Kwapich <mitrandir@fb.com>
# Date 1447094603 28800
# Node ID 663eff02a876b73f92fe3c1dbe7a526722269f92
# Parent  29ca5b764f888fcdc71024ab94dee18fc6814f3b
dirstate: fix filefoldmap incosistency on file delete

The _filefoldmap is not updated in when files are deleted from dirstate. In the
case where the file with the same but differently cased name is added afterwards
it renders _filefoldmap incorrect.  Those steps must occur to for a problem to
reproduce:
 - call status (with listunknown=True),
 - update working rectory to a commit which does a casefolding change (A -> a)
 - call status again (it will show the file "a" as deleted)

Unfortunately I'm unable to write a test for it because I don't know any
core-mercurial command able to reproduce those steps.

The bug was originally spotted when hgwatchman was enabled. It caused the
changeset contents change during hg rebase (one file unrelarted to changeset
was deleted in it after rebase).

The hgwatchman is able to hit it because when hgignore changes the hgwatchmans
overridestatus is calling original status with listunknown=True.

diff -r 29ca5b764f88 -r 663eff02a876 mercurial/dirstate.py
--- a/mercurial/dirstate.py	Mon Nov 09 09:41:20 2015 -0600
+++ b/mercurial/dirstate.py	Mon Nov 09 10:43:23 2015 -0800
@@ -445,6 +445,11 @@
         if self[f] not in "?r" and "_dirs" in self.__dict__:
             self._dirs.delpath(f)
 
+        if "_filefoldmap" in self.__dict__:
+            normed = util.normcase(f)
+            if normed in self._filefoldmap:
+                del self._filefoldmap[normed]
+
     def _addpath(self, f, state, mode, size, mtime):
         oldstate = self[f]
         if state == 'a' or oldstate == 'r':