optimize, fix topological sort.

Author: dimitri-yatsenko

datajoint/dependencies.py

@@ -106,6 +106,10 @@ def load(self, force=True):
             raise DataJointError("DataJoint can only work with acyclic dependencies")
         self._loaded = True
 
+    def topo_sort(self):
+        """:return:  list of nodes in lexcigraphical topological order"""
+        return list(nx.algorithms.dag.lexicographical_topological_sort(self))
+
     def parents(self, table_name, primary=None):
         """
         :param table_name: `schema`.`table`
@@ -142,18 +146,14 @@ def descendants(self, full_table_name):
         :return: all dependent tables sorted in topological order.  Self is included.
         """
         self.load(force=False)
-        nodes = self.subgraph(nx.algorithms.dag.descendants(self, full_table_name))
-        return [full_table_name] + list(nx.algorithms.dag.topological_sort(nodes))
+        nodes = self.subgraph(nx.algorithms.dag.descendants(self, full_table_name)).copy()
+        return [full_table_name] + nodes.topo_sort()
 
     def ancestors(self, full_table_name):
         """
         :param full_table_name:  In form `schema`.`table_name`
         :return: all dependent tables sorted in topological order.  Self is included.
         """
         self.load(force=False)
-        nodes = self.subgraph(nx.algorithms.dag.ancestors(self, full_table_name))
-        return list(
-            reversed(
-                list(nx.algorithms.dag.topological_sort(nodes)) + [full_table_name]
-            )
-        )
+        nodes = self.subgraph(nx.algorithms.dag.ancestors(self, full_table_name)).copy()
+        return reversed(nodes.topo_sort() + [full_table_name])

datajoint/diagram.py

@@ -177,14 +177,6 @@ def is_part(part, master):
             )
             return self
 
-        def topological_sort(self):
-            """:return:  list of nodes in lexcigraphical topological order"""
-            return list(
-                nx.algorithms.dag.lexicographical_topological_sort(
-                    nx.DiGraph(self).subgraph(self.nodes_to_show)
-                )
-            )
-
         def __add__(self, arg):
             """
             :param arg: either another Diagram or a positive integer.

datajoint/schemas.py

@@ -453,7 +453,7 @@ def replace(s):
 
         diagram = Diagram(self)
         body = "\n\n".join(
-            make_class_definition(table) for table in diagram.topological_sort()
+            make_class_definition(table) for table in diagram.topo_sort()
         )
         python_code = "\n\n".join(
             (
@@ -484,7 +484,7 @@ def list_tables(self):
             t
             for d, t in (
                 full_t.replace("`", "").split(".")
-                for full_t in Diagram(self).topological_sort()
+                for full_t in Diagram(self).topo_sort()
             )
             if d == self.database
         ]

datajoint/table.py

@@ -217,7 +217,6 @@ def children(self, primary=None, as_objects=False, foreign_key_info=False):
 
     def descendants(self, as_objects=False):
         """
-
         :param as_objects: False - a list of table names; True - a list of table objects.
         :return: list of tables descendants in topological order.
         """

tests/test_cli.py

@@ -3,7 +3,6 @@
 """
 
 import json
-import ast
 import subprocess
 import pytest
 import datajoint as dj

tests/test_schema.py

@@ -217,6 +217,13 @@ def test_list_tables(schema_simp):
     actual = set(schema_simp.list_tables())
     assert actual == expected, f"Missing from list_tables(): {expected - actual}"
 
+def test_schema_save_any(schema_any):
+    assert "class Experiment(dj.Imported)" in schema_any.code
+
+
+def test_schema_save_empty(schema_empty):
+    assert "class Experiment(dj.Imported)" in schema_empty.code
+
 
 def test_uppercase_schema(db_creds_root):
     """