py3: fix test-remotefilelog-repack.t

This is uglier, but more obviously correct in my opinion. I guess
Python 3 doesn't hang on to the exception as long, which seems
reasonable.

Differential Revision: https://phab.mercurial-scm.org/D5781

contrib/python3-whitelist

@@ -603,6 +603,7 b' test-remotefilelog-permissions.t'
 test-remotefilelog-permisssions.t
 test-remotefilelog-prefetch.t
 test-remotefilelog-pull-noshallow.t
+test-remotefilelog-repack.t
 test-remotefilelog-share.t
 test-remotefilelog-sparse.t
 test-remotefilelog-tags.t

hgext/remotefilelog/basestore.py

@@ -410,14 +410,16 b' class baseunionstore(object):'
         def wrapped(self, *args, **kwargs):
             retrylog = self.retrylog or noop
             funcname = fn.__name__
-            for i in pycompat.xrange(self.numattempts):
+            i = 0
+            while i < self.numattempts:
                 if i > 0:
                     retrylog('re-attempting (n=%d) %s\n' % (i, funcname))
                     self.markforrefresh()
+                i += 1
                 try:
                     return fn(self, *args, **kwargs)
                 except KeyError:
-                    pass
+                    if i == self.numattempts:
             # retries exhausted
             retrylog('retries exhausted in %s, raising KeyError\n' %
                      pycompat.sysbytes(funcname))