diff --git a/mercurial/simplemerge.py b/mercurial/simplemerge.py
--- a/mercurial/simplemerge.py
+++ b/mercurial/simplemerge.py
@@ -402,31 +402,6 @@
 
         return sl
 
-    def find_unconflicted(self):
-        """Return a list of ranges in base that are not conflicted."""
-        am = mdiff.get_matching_blocks(self.basetext, self.atext)
-        bm = mdiff.get_matching_blocks(self.basetext, self.btext)
-
-        unc = []
-
-        while am and bm:
-            # there is an unconflicted block at i; how long does it
-            # extend?  until whichever one ends earlier.
-            a1 = am[0][0]
-            a2 = a1 + am[0][2]
-            b1 = bm[0][0]
-            b2 = b1 + bm[0][2]
-            i = intersect((a1, a2), (b1, b2))
-            if i:
-                unc.append(i)
-
-            if a2 < b2:
-                del am[0]
-            else:
-                del bm[0]
-
-        return unc
-
 
 def _verifytext(text, path, ui, opts):
     """verifies that text is non-binary (unless opts[text] is passed,
diff --git a/tests/test-simplemerge.py b/tests/test-simplemerge.py
--- a/tests/test-simplemerge.py
+++ b/tests/test-simplemerge.py
@@ -141,8 +141,6 @@
         """No conflicts because nothing changed"""
         m3 = Merge3([b'aaa', b'bbb'], [b'aaa', b'bbb'], [b'aaa', b'bbb'])
 
-        self.assertEqual(m3.find_unconflicted(), [(0, 2)])
-
         self.assertEqual(
             list(m3.find_sync_regions()),
             [(0, 2, 0, 2, 0, 2), (2, 2, 2, 2, 2, 2)],
@@ -189,8 +187,6 @@
             [b'aaa', b'bbb'], [b'aaa', b'111', b'bbb'], [b'aaa', b'bbb']
         )
 
-        self.assertEqual(m3.find_unconflicted(), [(0, 1), (1, 2)])
-
         self.assertEqual(
             list(m3.find_sync_regions()),
             [(0, 1, 0, 1, 0, 1), (1, 2, 2, 3, 1, 2), (2, 2, 3, 3, 2, 2)],
@@ -271,8 +267,6 @@
             [b'aaa\n', b'222\n', b'bbb\n'],
         )
 
-        self.assertEqual(m3.find_unconflicted(), [(0, 1), (1, 2)])
-
         self.assertEqual(
             list(m3.find_sync_regions()),
             [(0, 1, 0, 1, 0, 1), (1, 2, 2, 3, 2, 3), (2, 2, 3, 3, 3, 3)],
@@ -323,8 +317,6 @@
             [b'aaa', b'222', b'bbb'],
         )
 
-        self.assertEqual(m3.find_unconflicted(), [(0, 1), (2, 3)])
-
         self.assertEqual(
             list(m3.find_sync_regions()),
             [(0, 1, 0, 1, 0, 1), (2, 3, 2, 3, 2, 3), (3, 3, 3, 3, 3, 3)],
@@ -338,8 +330,6 @@
             [b'aaa', b'222', b'222', b'222', b'222', b'bbb'],
         )
 
-        self.assertEqual(m3.find_unconflicted(), [(0, 1), (3, 4)])
-
         self.assertEqual(
             list(m3.find_sync_regions()),
             [(0, 1, 0, 1, 0, 1), (3, 4, 4, 5, 5, 6), (4, 4, 5, 5, 6, 6)],