Contig stitcher: optimize transitive closure calculation

Author: Donaim

micall/core/plot_contigs.py

@@ -454,24 +454,19 @@ def remove_transitive_edges(graph):
             ret[parent] = lst
         return ret
 
-    def get_all_ancestors(recur, lst, graph, ancestor_name):
-        if ancestor_name not in recur:
-            recur = recur.copy()
-            recur.add(ancestor_name)
-
-            if ancestor_name not in lst:
-                lst.append(ancestor_name)
-
-            existing_ancestors = graph.get(ancestor_name, [])
-            for existing in existing_ancestors:
-                get_all_ancestors(recur, lst, graph, existing)
+    def get_transitive_children(recur, lst, graph, current):
+        if current not in recur:
+            recur.add(current)
+            lst.append(current)
+            for child in graph.get(current, []):
+                get_transitive_children(recur, lst, graph, child)
 
     def transitive_closure(graph):
         ret = {}
         for parent, children in graph.items():
             lst = []
             for child in children:
-                get_all_ancestors(set(), lst, graph, child)
+                get_transitive_children(set(), lst, graph, child)
             ret[parent] = lst
         return ret