Added tests for removing unused nodes.

Author: VincentDerk

tests/test_compression.py

@@ -0,0 +1,110 @@
+import klay
+
+
+def test_propagate_simple_true():
+    c = klay.Circuit()
+    t = c.true_node()
+    f = c.false_node()
+    l1, l2 = c.literal_node(1), c.literal_node(2)
+
+    # test on input node
+    assert c.nb_nodes() == 4
+    and_node1 = c.and_node([t, l1]) # l1
+    and_node2 = c.and_node([l1, t]) # l1
+    or_node1 = c.or_node([l1, t]) # t
+    or_node2 = c.or_node([t, l1]) # t
+    assert c.nb_nodes() == 4
+
+    # test on intermediate node
+    l1_l2 = c.and_node([l1, l2])
+    assert c.nb_nodes() == 5
+    and_node1 = c.and_node([t, l1_l2]) # l1
+    and_node2 = c.and_node([l1_l2, t]) # l1
+    or_node1 = c.or_node([l1_l2, t]) # t
+    or_node2 = c.or_node([t, l1_l2]) # t
+    assert c.nb_nodes() == 5
+
+
+def test_propagate_simple_false():
+    c = klay.Circuit()
+    t = c.true_node()
+    f = c.false_node()
+    l1, l2 = c.literal_node(1), c.literal_node(2)
+
+    # test on input node
+    assert c.nb_nodes() == 4
+    and_node1 = c.and_node([f, l1])  # f
+    and_node2 = c.and_node([l1, f])  # f
+    or_node1 = c.or_node([l1, f])  # l1
+    or_node2 = c.or_node([f, l1])  # l1
+    assert c.nb_nodes() == 4
+
+    # test on intermediate node
+    l1_l2 = c.and_node([l1, l2])
+    assert c.nb_nodes() == 5
+    and_node1 = c.and_node([f, l1_l2])  # f
+    and_node2 = c.and_node([l1_l2, f])  # f
+    or_node1 = c.or_node([l1_l2, f])  # l1 & l2
+    or_node2 = c.or_node([f, l1_l2])  # l1 & l2
+    assert c.nb_nodes() == 5
+
+
+def test_propagate_simple_ternary():
+    """ test ternary nodes """
+    c = klay.Circuit()
+    t = c.true_node()
+    f = c.false_node()
+    l1, l2 = c.literal_node(1), c.literal_node(2)
+
+    # test on true
+    assert c.nb_nodes() == 4
+    and_node1 = c.and_node([t, l1, l2])  # l1 & l2
+    assert c.nb_nodes() == 5
+    and_node2 = c.and_node([l2, t, l1])  # l1 & l2
+    assert c.nb_nodes() == 5
+    or_node1 = c.or_node([l1, t, l2])  # t
+    assert c.nb_nodes() == 5
+    or_node2 = c.or_node([l2, l1, t])  # t
+    assert c.nb_nodes() == 5
+
+    # test on false
+    and_node3 = c.and_node([f, l1, l2])  # f
+    assert c.nb_nodes() == 5
+    and_node4 = c.and_node([l2, f, l1])  # f
+    assert c.nb_nodes() == 5
+    or_node3 = c.or_node([l1, f, l2])  # l1 | l2
+    assert c.nb_nodes() == 8, "Expected 8 nodes instead of 6, because l1 and l2 require dummy nodes for the OR-node."
+    or_node4 = c.or_node([l2, l1, f])  # l1 | l2
+    assert c.nb_nodes() == 8
+
+
+def test_removing_useless_nodes1():
+    c = klay.Circuit()
+    l1, l2, l3 = c.literal_node(1), c.literal_node(2), c.literal_node(3)
+    assert c.nb_nodes() == 3
+    and1 = c.and_node([l1, l2])
+    assert c.nb_nodes() == 4
+    or1 = c.or_node([and1, l3])
+    assert c.nb_nodes() == 6  # or1 + 1 dummy node
+    c.set_root(and1)
+    # and1 is root node; but or1 is in a layer above, unused.
+    assert c.nb_nodes() == 6
+    c.remove_unused_nodes()  # should remove or1 + 1 dummy node
+    assert c.nb_nodes() == 4, f"Expected 4 nodes instead of {c.nb_nodes()}"
+
+
+def test_removing_useless_nodes2():
+    c = klay.Circuit()
+    l1, l2, l3 = c.literal_node(1), c.literal_node(2), c.literal_node(3)
+    assert c.nb_nodes() == 3
+    and1 = c.and_node([l1, l2])
+    assert c.nb_nodes() == 4
+    or1 = c.or_node([and1, l3])
+    assert c.nb_nodes() == 6  # or1 + 1 dummy node
+    and2 = c.and_node([l1, l3])  # useless
+    assert c.nb_nodes() == 7
+    or2 = c.or_node([l1, l2])  # useless
+    assert c.nb_nodes() == 10  # or2 + 2 dummy nodes
+    c.set_root(or1)
+    c.remove_unused_nodes()  # should remove `and2`, `or2`, and 2 dummy nodes
+    assert c.nb_nodes() == 6, f"Expected 5 nodes instead of {c.nb_nodes()}"