Added test for three_block_tower and fixed a bug in three_block_tower code

opensourceware · opensourceware · commit 1f3b32f891ca · 2016-09-26T16:14:46.000+08:00
diff --git a/planning.py b/planning.py
@@ -195,15 +195,14 @@ def goal_test(kb):
 
     ## Actions
     #  Move
-    precond_pos = [expr('On(b, x)'), expr('Clear(b)'), expr('Clear(y)'), expr('Block(b)'),
-                   expr('Block(y)'), expr('b != x'), expr('b != y'), expr('x != y')]
+    precond_pos = [expr('On(b, x)'), expr('Clear(b)'), expr('Clear(y)'), expr('Block(b)'), expr('Block(y)')]
     precond_neg = []
     effect_add = [expr('On(b, y)'), expr('Clear(x)')]
     effect_rem = [expr('On(b, x)'), expr('Clear(y)')]
     move = Action(expr('Move(b, x, y)'), [precond_pos, precond_neg], [effect_add, effect_rem])
     
     #  MoveToTable
-    precond_pos = [expr('On(b, x)'), expr('Clear(b)'), expr('Block(b)'), expr('b != x')]
+    precond_pos = [expr('On(b, x)'), expr('Clear(b)'), expr('Block(b)')]
     precond_neg = []
     effect_add = [expr('On(b, Table)'), expr('Clear(x)')]
     effect_rem = [expr('On(b, x)')]
diff --git a/tests/test_planning.py b/tests/test_planning.py
@@ -47,6 +47,18 @@ def test_spare_tire():
         
     assert p.goal_test()
 
+def test_three_block_tower():
+    p = three_block_tower()
+    assert p.goal_test() is False
+    solution = [expr("MoveToTable(C, A)"),
+                expr("Move(B, Table, C)"),
+                expr("Move(A, Table, B)")]
+
+    for action in solution:
+        p.act(action)
+        
+    assert p.goal_test()
+
 def test_have_cake_and_eat_cake_too():
     p = have_cake_and_eat_cake_too()
     assert p.goal_test() is False
