diff -r 6b1049d71c3e -r f45a4a47f6a8 mercurial/filemerge.py
--- a/mercurial/filemerge.py	Fri Dec 03 21:41:43 2021 -0800
+++ b/mercurial/filemerge.py	Fri Dec 03 22:45:35 2021 -0800
@@ -1027,7 +1027,7 @@
                 util.unlink(d)
 
 
-def _filemerge(repo, wctx, mynode, orig, fcd, fco, fca, labels=None):
+def filemerge(repo, wctx, mynode, orig, fcd, fco, fca, labels=None):
     """perform a 3-way merge in the working directory
 
     premerge = whether this is a premerge
@@ -1277,10 +1277,6 @@
     return repo.wjoin(ctx.path())
 
 
-def filemerge(repo, wctx, mynode, orig, fcd, fco, fca, labels=None):
-    return _filemerge(repo, wctx, mynode, orig, fcd, fco, fca, labels=labels)
-
-
 def loadinternalmerge(ui, extname, registrarobj):
     """Load internal merge tool from specified registrarobj"""
     for name, func in pycompat.iteritems(registrarobj._table):