diff -r e9293c5f8bb9 -r 29e4a77b5305 hgext/shelve.py
--- a/hgext/shelve.py	Tue Nov 13 12:32:05 2018 -0800
+++ b/hgext/shelve.py	Tue Nov 13 17:14:47 2018 -0800
@@ -430,8 +430,12 @@
     shelvedfile(repo, name, 'shelve').writeinfo(info)
     bases = list(mutableancestors(repo[node]))
     shelvedfile(repo, name, 'hg').writebundle(bases, node)
+    # Create a matcher so that prefetch doesn't attempt to fetch the entire
+    # repository pointlessly.
+    match = scmutil.matchfiles(repo, repo[node].files())
     with shelvedfile(repo, name, patchextension).opener('wb') as fp:
-        cmdutil.exportfile(repo, [node], fp, opts=mdiff.diffopts(git=True))
+        cmdutil.exportfile(repo, [node], fp, opts=mdiff.diffopts(git=True),
+                           match=match)
 
 def _includeunknownfiles(repo, pats, opts, extra):
     s = repo.status(match=scmutil.match(repo[None], pats, opts),