diff -r cc2b537b1966 -r e7d7335819f4 mercurial/commands.py
--- a/mercurial/commands.py	Thu Feb 02 10:00:26 2017 +0100
+++ b/mercurial/commands.py	Thu Feb 02 10:01:00 2017 +0100
@@ -47,7 +47,6 @@
     patch,
     phases,
     pycompat,
-    repair,
     revlog,
     revset,
     scmutil,
@@ -1859,11 +1858,6 @@
     with repo.wlock(False):
         return cmdutil.copy(ui, repo, pats, opts)
 
-@command('debugrebuildfncache', [], '')
-def debugrebuildfncache(ui, repo):
-    """rebuild the fncache file"""
-    repair.rebuildfncache(ui, repo)
-
 @command('debugrename',
     [('r', 'rev', '', _('revision to debug'), _('REV'))],
     _('[-r REV] FILE'))