| from itertools import chain |
| import graphlib |
| import os |
| import unittest |
| |
| from test.support.script_helper import assert_python_ok |
| |
| class TestTopologicalSort(unittest.TestCase): |
| def _test_graph(self, graph, expected): |
| def static_order_with_groups(ts): |
| ts.prepare() |
| while ts.is_active(): |
| nodes = ts.get_ready() |
| for node in nodes: |
| ts.done(node) |
| yield nodes |
| |
| ts = graphlib.TopologicalSorter(graph) |
| self.assertEqual(list(static_order_with_groups(ts)), list(expected)) |
| |
| ts = graphlib.TopologicalSorter(graph) |
| self.assertEqual(list(ts.static_order()), list(chain(*expected))) |
| |
| def _assert_cycle(self, graph, cycle): |
| ts = graphlib.TopologicalSorter() |
| for node, dependson in graph.items(): |
| ts.add(node, *dependson) |
| try: |
| ts.prepare() |
| except graphlib.CycleError as e: |
| msg, seq = e.args |
| self.assertIn(" ".join(map(str, cycle)), " ".join(map(str, seq * 2))) |
| else: |
| raise |
| |
| def test_simple_cases(self): |
| self._test_graph( |
| {2: {11}, 9: {11, 8}, 10: {11, 3}, 11: {7, 5}, 8: {7, 3}}, |
| [(3, 5, 7), (11, 8), (2, 10, 9)], |
| ) |
| |
| self._test_graph({1: {}}, [(1,)]) |
| |
| self._test_graph( |
| {x: {x + 1} for x in range(10)}, [(x,) for x in range(10, -1, -1)] |
| ) |
| |
| self._test_graph( |
| {2: {3}, 3: {4}, 4: {5}, 5: {1}, 11: {12}, 12: {13}, 13: {14}, 14: {15}}, |
| [(1, 15), (5, 14), (4, 13), (3, 12), (2, 11)], |
| ) |
| |
| self._test_graph( |
| { |
| 0: [1, 2], |
| 1: [3], |
| 2: [5, 6], |
| 3: [4], |
| 4: [9], |
| 5: [3], |
| 6: [7], |
| 7: [8], |
| 8: [4], |
| 9: [], |
| }, |
| [(9,), (4,), (3, 8), (1, 5, 7), (6,), (2,), (0,)], |
| ) |
| |
| self._test_graph({0: [1, 2], 1: [], 2: [3], 3: []}, [(1, 3), (2,), (0,)]) |
| |
| self._test_graph( |
| {0: [1, 2], 1: [], 2: [3], 3: [], 4: [5], 5: [6], 6: []}, |
| [(1, 3, 6), (2, 5), (0, 4)], |
| ) |
| |
| def test_no_dependencies(self): |
| self._test_graph({1: {2}, 3: {4}, 5: {6}}, [(2, 4, 6), (1, 3, 5)]) |
| |
| self._test_graph({1: set(), 3: set(), 5: set()}, [(1, 3, 5)]) |
| |
| def test_the_node_multiple_times(self): |
| # Test same node multiple times in dependencies |
| self._test_graph({1: {2}, 3: {4}, 0: [2, 4, 4, 4, 4, 4]}, [(2, 4), (1, 3, 0)]) |
| |
| # Test adding the same dependency multiple times |
| ts = graphlib.TopologicalSorter() |
| ts.add(1, 2) |
| ts.add(1, 2) |
| ts.add(1, 2) |
| self.assertEqual([*ts.static_order()], [2, 1]) |
| |
| def test_graph_with_iterables(self): |
| dependson = (2 * x + 1 for x in range(5)) |
| ts = graphlib.TopologicalSorter({0: dependson}) |
| self.assertEqual(list(ts.static_order()), [1, 3, 5, 7, 9, 0]) |
| |
| def test_add_dependencies_for_same_node_incrementally(self): |
| # Test same node multiple times |
| ts = graphlib.TopologicalSorter() |
| ts.add(1, 2) |
| ts.add(1, 3) |
| ts.add(1, 4) |
| ts.add(1, 5) |
| |
| ts2 = graphlib.TopologicalSorter({1: {2, 3, 4, 5}}) |
| self.assertEqual([*ts.static_order()], [*ts2.static_order()]) |
| |
| def test_empty(self): |
| self._test_graph({}, []) |
| |
| def test_cycle(self): |
| # Self cycle |
| self._assert_cycle({1: {1}}, [1, 1]) |
| # Simple cycle |
| self._assert_cycle({1: {2}, 2: {1}}, [1, 2, 1]) |
| # Indirect cycle |
| self._assert_cycle({1: {2}, 2: {3}, 3: {1}}, [1, 3, 2, 1]) |
| # not all elements involved in a cycle |
| self._assert_cycle({1: {2}, 2: {3}, 3: {1}, 5: {4}, 4: {6}}, [1, 3, 2, 1]) |
| # Multiple cycles |
| self._assert_cycle({1: {2}, 2: {1}, 3: {4}, 4: {5}, 6: {7}, 7: {6}}, [1, 2, 1]) |
| # Cycle in the middle of the graph |
| self._assert_cycle({1: {2}, 2: {3}, 3: {2, 4}, 4: {5}}, [3, 2]) |
| |
| def test_calls_before_prepare(self): |
| ts = graphlib.TopologicalSorter() |
| |
| with self.assertRaisesRegex(ValueError, r"prepare\(\) must be called first"): |
| ts.get_ready() |
| with self.assertRaisesRegex(ValueError, r"prepare\(\) must be called first"): |
| ts.done(3) |
| with self.assertRaisesRegex(ValueError, r"prepare\(\) must be called first"): |
| ts.is_active() |
| |
| def test_prepare_multiple_times(self): |
| ts = graphlib.TopologicalSorter() |
| ts.prepare() |
| with self.assertRaisesRegex(ValueError, r"cannot prepare\(\) more than once"): |
| ts.prepare() |
| |
| def test_invalid_nodes_in_done(self): |
| ts = graphlib.TopologicalSorter() |
| ts.add(1, 2, 3, 4) |
| ts.add(2, 3, 4) |
| ts.prepare() |
| ts.get_ready() |
| |
| with self.assertRaisesRegex(ValueError, "node 2 was not passed out"): |
| ts.done(2) |
| with self.assertRaisesRegex(ValueError, r"node 24 was not added using add\(\)"): |
| ts.done(24) |
| |
| def test_done(self): |
| ts = graphlib.TopologicalSorter() |
| ts.add(1, 2, 3, 4) |
| ts.add(2, 3) |
| ts.prepare() |
| |
| self.assertEqual(ts.get_ready(), (3, 4)) |
| # If we don't mark anything as done, get_ready() returns nothing |
| self.assertEqual(ts.get_ready(), ()) |
| ts.done(3) |
| # Now 2 becomes available as 3 is done |
| self.assertEqual(ts.get_ready(), (2,)) |
| self.assertEqual(ts.get_ready(), ()) |
| ts.done(4) |
| ts.done(2) |
| # Only 1 is missing |
| self.assertEqual(ts.get_ready(), (1,)) |
| self.assertEqual(ts.get_ready(), ()) |
| ts.done(1) |
| self.assertEqual(ts.get_ready(), ()) |
| self.assertFalse(ts.is_active()) |
| |
| def test_is_active(self): |
| ts = graphlib.TopologicalSorter() |
| ts.add(1, 2) |
| ts.prepare() |
| |
| self.assertTrue(ts.is_active()) |
| self.assertEqual(ts.get_ready(), (2,)) |
| self.assertTrue(ts.is_active()) |
| ts.done(2) |
| self.assertTrue(ts.is_active()) |
| self.assertEqual(ts.get_ready(), (1,)) |
| self.assertTrue(ts.is_active()) |
| ts.done(1) |
| self.assertFalse(ts.is_active()) |
| |
| def test_not_hashable_nodes(self): |
| ts = graphlib.TopologicalSorter() |
| self.assertRaises(TypeError, ts.add, dict(), 1) |
| self.assertRaises(TypeError, ts.add, 1, dict()) |
| self.assertRaises(TypeError, ts.add, dict(), dict()) |
| |
| def test_order_of_insertion_does_not_matter_between_groups(self): |
| def get_groups(ts): |
| ts.prepare() |
| while ts.is_active(): |
| nodes = ts.get_ready() |
| ts.done(*nodes) |
| yield set(nodes) |
| |
| ts = graphlib.TopologicalSorter() |
| ts.add(3, 2, 1) |
| ts.add(1, 0) |
| ts.add(4, 5) |
| ts.add(6, 7) |
| ts.add(4, 7) |
| |
| ts2 = graphlib.TopologicalSorter() |
| ts2.add(1, 0) |
| ts2.add(3, 2, 1) |
| ts2.add(4, 7) |
| ts2.add(6, 7) |
| ts2.add(4, 5) |
| |
| self.assertEqual(list(get_groups(ts)), list(get_groups(ts2))) |
| |
| def test_static_order_does_not_change_with_the_hash_seed(self): |
| def check_order_with_hash_seed(seed): |
| code = """if 1: |
| import graphlib |
| ts = graphlib.TopologicalSorter() |
| ts.add('blech', 'bluch', 'hola') |
| ts.add('abcd', 'blech', 'bluch', 'a', 'b') |
| ts.add('a', 'a string', 'something', 'b') |
| ts.add('bluch', 'hola', 'abcde', 'a', 'b') |
| print(list(ts.static_order())) |
| """ |
| env = os.environ.copy() |
| # signal to assert_python not to do a copy |
| # of os.environ on its own |
| env["__cleanenv"] = True |
| env["PYTHONHASHSEED"] = str(seed) |
| out = assert_python_ok("-c", code, **env) |
| return out |
| |
| run1 = check_order_with_hash_seed(1234) |
| run2 = check_order_with_hash_seed(31415) |
| |
| self.assertNotEqual(run1, "") |
| self.assertNotEqual(run2, "") |
| self.assertEqual(run1, run2) |
