[PATCH] merge: report file/directory collisions properly

[Patrick Mezard]

# HG changeset patch
# User Patrick Mezard <pmezard at gmail.com>
# Date 1187116733 -7200
# Node ID 124f1f04a7fba43479e619f620fb5b520114604a
# Parent  f0f22f1776bf2994d91a7b6f42c7109160aa6587
merge: report file/directory collisions properly

diff --git a/mercurial/merge.py b/mercurial/merge.py
--- a/mercurial/merge.py
+++ b/mercurial/merge.py
@@ -7,7 +7,7 @@
 
 from node import *
 from i18n import _
-import errno, util, os, tempfile, context, heapq
+import errno, util, os, tempfile, context, heapq, strutil
 
 def filemerge(repo, fw, fd, fo, wctx, mctx):
     """perform a 3-way merge in the working directory
@@ -72,13 +72,26 @@ def checkunknown(wctx, mctx):
 
 def checkcollision(mctx):
     "check for case folding collisions in the destination context"
+    def reportcollision(p1, p2):
+        path1, type1 = p1
+        path2, type2 = p2
+        format = _("case-folding collision between %s %%s and %s %%s" 
+                   % (type1, type2))
+        raise util.Abort(format % (path1, path2))
+
     folded = {}
     for fn in mctx.manifest():
+        for c in strutil.findall(fn, '/'):
+            fnpart = fn[:c]
+            fold = fnpart.lower()
+            if fold in folded and folded[fold][0] != fnpart:
+                reportcollision(folded[fold], (fnpart, 'directory'))
+            folded[fold] = (fnpart, 'directory')
+
         fold = fn.lower()
         if fold in folded:
-            raise util.Abort(_("case-folding collision between %s and %s")
-                             % (fn, folded[fold]))
-        folded[fold] = fn
+            reportcollision(folded[fold], (fn, 'file'))
+        folded[fold] = (fn, 'file')
 
 def forgetremoved(wctx, mctx):
     """