Fix unexpected rooting side effects of Tree.mrca()

Sets `collapse_unrooted_basal_bifurcation=False` in call to `Tree.encode_bipartitions` inside `Tree.mrca`. Closes jeetsukumaran#152.
mmore500 · Mar 30, 2023 · 9d56b8c · 9d56b8c
1 parent 34fd844
commit 9d56b8c
Showing 1 changed file with 4 additions and 1 deletion.
diff --git a/src/dendropy/datamodel/treemodel/_tree.py b/src/dendropy/datamodel/treemodel/_tree.py
@@ -1550,7 +1550,10 @@ def mrca(self, **kwargs):
         if start_node.edge.bipartition.leafset_bitmask == 0 or not kwargs.get(
             "is_bipartitions_updated", True
         ):
-            self.encode_bipartitions(suppress_unifurcations=False)
+            self.encode_bipartitions(
+                suppress_unifurcations=False,
+                collapse_unrooted_basal_bifurcation=False,
+            )
 
         if (
             start_node.edge.bipartition.leafset_bitmask & leafset_bitmask