Possible Patch: Allow Renaming to Different Case

[Michael Cook]

OK, one more patch for the night (hey this is fun!). I needed to rename 
some files to fix their case, but I wasn't allowed to because the 
destination file was said to already exist (I'm on OS X, which is case 
insensitive). Below is a simple change to allow renaming in the case 
that the two filenames are identical ignoring case, which fixes this 
bug.

Now I don't know if you want to apply this, as on filesystems that ARE 
case sensitive, this could lead to unwanted behavior. In the situation 
where one directory has two files with the same name but different case 
(README and ReadMe for example), this patch would let you rename README 
to ReadMe, overwriting the original ReadMe file without complaining. I 
can't think of a simple solution to this problem that can handle both 
cases correctly. My only two thoughts are to either check some unique 
property of the file to see if the two files are the same (say the 
inode number), or to make a check to see if you are on a 
case-insensitive filesystem and test the condition in the patch only if 
that is true.

--- bzr/bzrlib/branch.py        Thu Apr 14 21:50:23 2005
+++ bzr-dev/bzrlib/branch.py    Sun Apr 24 20:45:45 2005
@@ -773,7 +773,8 @@
          if not tree.has_filename(from_rel):
              bailout("can't rename: old working file %r does not exist" 
% from_rel)
          if tree.has_filename(to_rel):
-            bailout("can't rename: new working file %r already exists" 
% to_rel)
+            if from_rel.lower() != to_rel.lower():
+                bailout("can't rename: new working file %r already 
exists" % to_rel)

          file_id = inv.path2id(from_rel)
          if file_id == None: