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Author: petrelharp

c/tskit/tables.h

@@ -869,8 +869,8 @@ this option adds all edges.
  */
 #define TSK_UNION_ALL_EDGES (1 << 2)
 /**
-By default, union only adds only mutations on newly added edges;
-this option adds all mutations.
+By default, union only adds only mutations on newly added edges, and
+sites for those mutations; this option adds all mutations and all sites.
  */
 #define TSK_UNION_ALL_MUTATIONS (1 << 3)
 /** @} */

python/tskit/tables.py

@@ -4355,9 +4355,9 @@ def union(
             ``tskit.NULL`` if the node is not present in ``self`` (in which case it
             will be added to self).
         :param bool all_edges: If True, then all edges in ``other`` are added
-            to ``self``. Must have ``check_shared_equality=False``.
+            to ``self``.
         :param bool all_mutations: If True, then all mutations in ``other`` are added
-            to ``self``. Must have ``check_shared_equality=False``.
+            to ``self``.
         :param bool check_shared_equality: If True, the shared portions of the
             table collections will be checked for equality.
         :param bool add_populations: If True, nodes new to ``self`` will be