Fixed database typo and removed unnecessary class identifier.

venv/Lib/site-packages/networkx/utils/tests/test_heaps.py

@@ -0,0 +1,130 @@
+import pytest
+import networkx as nx
+from networkx.utils import BinaryHeap, PairingHeap
+
+
+class X:
+    def __eq__(self, other):
+        raise self is other
+
+    def __ne__(self, other):
+        raise self is not other
+
+    def __lt__(self, other):
+        raise TypeError("cannot compare")
+
+    def __le__(self, other):
+        raise TypeError("cannot compare")
+
+    def __ge__(self, other):
+        raise TypeError("cannot compare")
+
+    def __gt__(self, other):
+        raise TypeError("cannot compare")
+
+    def __hash__(self):
+        return hash(id(self))
+
+
+x = X()
+
+
+data = [  # min should not invent an element.
+    ("min", nx.NetworkXError),
+    # Popping an empty heap should fail.
+    ("pop", nx.NetworkXError),
+    # Getting nonexisting elements should return None.
+    ("get", 0, None),
+    ("get", x, None),
+    ("get", None, None),
+    # Inserting a new key should succeed.
+    ("insert", x, 1, True),
+    ("get", x, 1),
+    ("min", (x, 1)),
+    # min should not pop the top element.
+    ("min", (x, 1)),
+    # Inserting a new key of different type should succeed.
+    ("insert", 1, -2.0, True),
+    # int and float values should interop.
+    ("min", (1, -2.0)),
+    # pop removes minimum-valued element.
+    ("insert", 3, -(10 ** 100), True),
+    ("insert", 4, 5, True),
+    ("pop", (3, -(10 ** 100))),
+    ("pop", (1, -2.0)),
+    # Decrease-insert should succeed.
+    ("insert", 4, -50, True),
+    ("insert", 4, -60, False, True),
+    # Decrease-insert should not create duplicate keys.
+    ("pop", (4, -60)),
+    ("pop", (x, 1)),
+    # Popping all elements should empty the heap.
+    ("min", nx.NetworkXError),
+    ("pop", nx.NetworkXError),
+    # Non-value-changing insert should fail.
+    ("insert", x, 0, True),
+    ("insert", x, 0, False, False),
+    ("min", (x, 0)),
+    ("insert", x, 0, True, False),
+    ("min", (x, 0)),
+    # Failed insert should not create duplicate keys.
+    ("pop", (x, 0)),
+    ("pop", nx.NetworkXError),
+    # Increase-insert should succeed when allowed.
+    ("insert", None, 0, True),
+    ("insert", 2, -1, True),
+    ("min", (2, -1)),
+    ("insert", 2, 1, True, False),
+    ("min", (None, 0)),
+    # Increase-insert should fail when disallowed.
+    ("insert", None, 2, False, False),
+    ("min", (None, 0)),
+    # Failed increase-insert should not create duplicate keys.
+    ("pop", (None, 0)),
+    ("pop", (2, 1)),
+    ("min", nx.NetworkXError),
+    ("pop", nx.NetworkXError),
+]
+
+
+def _test_heap_class(cls, *args, **kwargs):
+    heap = cls(*args, **kwargs)
+    # Basic behavioral test
+    for op in data:
+        if op[-1] is not nx.NetworkXError:
+            assert op[-1] == getattr(heap, op[0])(*op[1:-1])
+        else:
+            pytest.raises(op[-1], getattr(heap, op[0]), *op[1:-1])
+    # Coverage test.
+    for i in range(99, -1, -1):
+        assert heap.insert(i, i)
+    for i in range(50):
+        assert heap.pop() == (i, i)
+    for i in range(100):
+        assert heap.insert(i, i) == (i < 50)
+    for i in range(100):
+        assert not heap.insert(i, i + 1)
+    for i in range(50):
+        assert heap.pop() == (i, i)
+    for i in range(100):
+        assert heap.insert(i, i + 1) == (i < 50)
+    for i in range(49):
+        assert heap.pop() == (i, i + 1)
+    assert sorted([heap.pop(), heap.pop()]) == [(49, 50), (50, 50)]
+    for i in range(51, 100):
+        assert not heap.insert(i, i + 1, True)
+    for i in range(51, 70):
+        assert heap.pop() == (i, i + 1)
+    for i in range(100):
+        assert heap.insert(i, i)
+    for i in range(100):
+        assert heap.pop() == (i, i)
+    pytest.raises(nx.NetworkXError, heap.pop)
+
+
+def test_PairingHeap():
+    _test_heap_class(PairingHeap)
+
+
+def test_BinaryHeap():
+    _test_heap_class(BinaryHeap)