convert: config option for git rename limit By default, Git applies rename and copy detection to 400 files. The diff.renamelimit config option and -l argument to diff commands can override this. As part of converting some repositories in the wild, I was hitting the default limit. Unfortunately, the warnings that Git prints in this scenario are swallowed because the process running functionality in common.py redirects stderr to /dev/null by default. This seems like a bug, but a bug for another day. This commit establishes a config option to send the rename limit through to `git diff-tree`. The added tests demonstrate a too-low rename limit doesn't result in copy metadata being recorded.

--- a/hgext/convert/git.py	Thu Dec 22 01:09:45 2016 +0900
+++ b/hgext/convert/git.py	Sun Dec 18 12:53:20 2016 -0800
@@ -78,6 +78,10 @@
                                              False)
             if findcopiesharder:
                 self.simopt.append('--find-copies-harder')
+
+            renamelimit = ui.configint('convert', 'git.renamelimit',
+                                       default=400)
+            self.simopt.append('-l%d' % renamelimit)
         else:
             self.simopt = []