diff --git a/hgext/extdiff.py b/hgext/extdiff.py
--- a/hgext/extdiff.py
+++ b/hgext/extdiff.py
@@ -171,7 +171,7 @@
         node2 = scmutil.revsingle(repo, change, None).node()
         node1a, node1b = repo.changelog.parents(node2)
     else:
-        node1a, node2 = scmutil.revpair(repo, revs)
+        node1a, node2 = scmutil.revpairnodes(repo, revs)
         if not revs:
             node1b = repo.dirstate.p2()
         else:
diff --git a/mercurial/commands.py b/mercurial/commands.py
--- a/mercurial/commands.py
+++ b/mercurial/commands.py
@@ -1878,7 +1878,7 @@
         node1 = repo[node2].p1().node()
     else:
         repo = scmutil.unhidehashlikerevs(repo, revs, 'nowarn')
-        node1, node2 = scmutil.revpair(repo, revs)
+        node1, node2 = scmutil.revpairnodes(repo, revs)
 
     if reverse:
         node1, node2 = node2, node1
@@ -4880,7 +4880,7 @@
         node1 = repo[node2].p1().node()
     else:
         repo = scmutil.unhidehashlikerevs(repo, revs, 'nowarn')
-        node1, node2 = scmutil.revpair(repo, revs)
+        node1, node2 = scmutil.revpairnodes(repo, revs)
 
     if pats or ui.configbool('commands', 'status.relative'):
         cwd = repo.getcwd()
diff --git a/mercurial/fileset.py b/mercurial/fileset.py
--- a/mercurial/fileset.py
+++ b/mercurial/fileset.py
@@ -513,7 +513,7 @@
     revspec = getstring(r, reverr)
     if not revspec:
         raise error.ParseError(reverr)
-    basenode, node = scmutil.revpair(repo, [baserevspec, revspec])
+    basenode, node = scmutil.revpairnodes(repo, [baserevspec, revspec])
     basectx = repo[basenode]
     ctx = repo[node]
     return getset(mctx.switch(ctx, _buildstatus(ctx, x, basectx=basectx)), x)
diff --git a/mercurial/scmutil.py b/mercurial/scmutil.py
--- a/mercurial/scmutil.py
+++ b/mercurial/scmutil.py
@@ -446,6 +446,9 @@
     tree = revsetlang.parse(revspec)
     return tree and tree[0] in ('range', 'rangepre', 'rangepost', 'rangeall')
 
+def revpairnodes(repo, revs):
+    return revpair(repo, revs)
+
 def revpair(repo, revs):
     if not revs:
         return repo.dirstate.p1(), None
diff --git a/tests/autodiff.py b/tests/autodiff.py
--- a/tests/autodiff.py
+++ b/tests/autodiff.py
@@ -40,7 +40,7 @@
     else:
         raise error.Abort(b'--git must be yes, no or auto')
 
-    node1, node2 = scmutil.revpair(repo, [])
+    node1, node2 = scmutil.revpairnodes(repo, [])
     m = scmutil.match(repo[node2], pats, opts)
     it = patch.diff(repo, node1, node2, match=m, opts=diffopts,
                     losedatafn=losedatafn)