def test_heap_discard(): h1 = Heap() h2 = h1.branch() h3 = h2.branch() h = h2.discard(h3) assert h3.prev is h1 assert h3 is h h0 = Heap() v0 = h0.newvar() h1 = h0.branch() v1 = h1.newvar() h2 = h1.branch() v2 = h2.newvar() h2.add_trail(v0) v0.binding = 1 h2.add_trail(v1) v1.binding = 2 h3 = h2.branch() h3.add_trail(v2) v2.binding = 3 h = h2.discard(h3) assert h3.prev is h1 assert h3 is h assert h3.revert_upto(h0) assert v0.binding is None assert v1.binding is None assert v2.binding == 3 # not backtracked, because it goes away
def test_heap_discard_variable_shunting(): h0 = Heap() v0 = h0.newvar() h1 = h0.branch() v1a = h1.newvar() v1b = h1.newvar() h2 = h1.branch() v2 = h1.newvar() h2.add_trail(v0) v0.binding = 1 h2.add_trail(v1a) v1a.binding = 2 h = h1.discard(h2) assert h2.prev is h0 assert h2 is h assert h1.discarded assert h1.prev is h2 h2.add_trail(v1b) v1b.binding = 3 assert h2.revert_upto(h0) assert v0.binding is None assert v1a.binding == 2 # not backtracked, because it goes away assert v1b.binding == 3 # not backtracked, because it goes away
def test_heap(): h1 = Heap() v1 = h1.newvar() v2 = h1.newvar() h1.add_trail(v1) v1.binding = 1 h2 = h1.branch() h2.add_trail(v1) v1.binding = 2 h2.add_trail(v2) v2.binding = 3 h3 = h2.revert_upto(h1) assert v1.binding == 1 assert v2.binding is None assert h3 is h2 h1 = Heap() h2 = h1.revert_upto(h1) assert h2 is h1 h1 = Heap() h2 = h1.branch() h3 = h2.revert_upto(h1, discard_choicepoint=True) assert h3 is h1
def test_heap_dont_trail_new(): h1 = Heap() v1 = h1.newvar() h1.add_trail(v1) v1.binding = 1 h2 = h1.branch() v2 = h2.newvar() h2.add_trail(v1) v1.binding = 2 h2.add_trail(v2) v2.binding = 3 h3 = h2.revert_upto(h1) assert v1.binding == 1 assert v2.binding == 3 # wasn't undone, because v2 dies assert h3 is h2
def test_current_output(): e = Engine() h = Heap() X = h.newvar() impl_current_output(e, h, X) assert X.dereference(h).name() == e.streamwrapper.current_outstream.alias
def test_current_output(): e = Engine() h = Heap() X = h.newvar() impl_current_output(e, h, X) assert X.dereference(h).name() == e.streamwrapper.current_outstream.alias