diff --git a/mercurial/commit.py b/mercurial/commit.py
--- a/mercurial/commit.py
+++ b/mercurial/commit.py
@@ -147,7 +147,7 @@
         # some cases.
         ms = mergestate.mergestate.read(repo)
         if ms.active():
-            for fname in sorted(ms._stateextras.keys()):
+            for fname in sorted(ms.extras().keys()):
                 might_removed = ms.extras(fname).get(b'merge-removal-candidate')
                 if might_removed == b'yes':
                     if fname in ctx:
diff --git a/mercurial/debugcommands.py b/mercurial/debugcommands.py
--- a/mercurial/debugcommands.py
+++ b/mercurial/debugcommands.py
@@ -2107,7 +2107,7 @@
     fm_files.end()
 
     fm_extras = fm.nested(b'extras')
-    for f, d in sorted(pycompat.iteritems(ms._stateextras)):
+    for f, d in sorted(pycompat.iteritems(ms.extras())):
         if f in ms:
             # If file is in mergestate, we have already processed it's extras
             continue
diff --git a/mercurial/mergestate.py b/mercurial/mergestate.py
--- a/mercurial/mergestate.py
+++ b/mercurial/mergestate.py
@@ -305,7 +305,12 @@
             ):
                 yield f
 
-    def extras(self, filename):
+    def extras(self, filename=None):
+        """ return extras stored with the mergestate
+
+        if filename is passed, extras for that file is only returned """
+        if filename is None:
+            return self._stateextras
         return self._stateextras[filename]
 
     def _resolve(self, preresolve, dfile, wctx):