--- a/hgext3rd/evolve/obshistory.py	Mon Jan 13 15:04:02 2020 +0700
+++ b/hgext3rd/evolve/obshistory.py	Mon Jan 13 15:05:34 2020 +0700
@@ -830,31 +830,3 @@
 @eh.wrapfunction(obsutil, 'obsfateverb')
 def obsfateverb(orig, *args, **kwargs):
     return _successorsetverb(*args, **kwargs)[b'verb']
-
-def successorsetallmarkers(successorset, pathscache):
-    """compute all successors of a successorset.
-
-    pathscache must contains all successors starting from selected nodes
-    or revision. This way, iterating on each successor, we can take all
-    precursors and have the subgraph of all obsmarkers between roots to
-    successors.
-    """
-
-    markers = set()
-    seen = set()
-
-    for successor in successorset:
-        stack = [successor]
-
-        while stack:
-            element = stack.pop()
-            seen.add(element)
-            for prec, mark in pathscache.get(element, []):
-                if prec not in seen:
-                    # Process element precursors
-                    stack.append(prec)
-
-                if mark not in markers:
-                    markers.add(mark)
-
-    return markers