tests for the transitions file

tests/test_transitions.py

@@ -2,10 +2,64 @@
 # -*- coding: utf-8 -*-
 
 """Tests for `flatland` package."""
+from flatland.core.transitions import RailEnvTransitions, GridTransitions
+import pytest
+
+
+def test_valid_railenv_transitions():
+    rail_env_trans = RailEnvTransitions()
+
+    # dir_map = {'N': 0,
+    #            'E': 1,
+    #            'S': 2,
+    #            'W': 3}
+
+    for i in range(2):
+        assert (rail_env_trans.get_transitions_from_orientation(int('1100110000110011', 2), i) == (1, 1, 0, 0))
+        assert(rail_env_trans.get_transitions_from_orientation(int('1100110000110011', 2), 2+i) == (0, 0, 1, 1))
+
+    no_transition_cell = int('0000000000000000', 2)
+
+    for i in range(4):
+        assert(rail_env_trans.get_transitions_from_orientation(no_transition_cell, i) == (0, 0, 0, 0))
+
+    # Facing south, going south
+    north_south_transition = rail_env_trans.set_transitions_from_orientation(no_transition_cell, 2, (0, 0, 1, 0))
+    assert(rail_env_trans.set_transition_from_orientation_to_direction(north_south_transition, 2, 2, 0) ==
+           no_transition_cell)
+    assert(rail_env_trans.get_transition_from_orientation_to_direction(north_south_transition, 2, 2))
+
+    # Facing north, going east
+    south_east_transition = rail_env_trans.set_transition_from_orientation_to_direction(no_transition_cell, 0, 1, 1)
+    assert(rail_env_trans.get_transition_from_orientation_to_direction(south_east_transition, 0, 1))
+
+    # The opposite transitions are not feasible
+    assert(not rail_env_trans.get_transition_from_orientation_to_direction(north_south_transition, 2, 0))
+    assert(not rail_env_trans.get_transition_from_orientation_to_direction(south_east_transition, 2, 1))
+
+    east_west_transition = rail_env_trans.rotate_transition(north_south_transition, 90)
+    north_west_transition = rail_env_trans.rotate_transition(south_east_transition, 180)
+
+    # Facing west, going west
+    assert(rail_env_trans.get_transition_from_orientation_to_direction(east_west_transition, 3, 3))
+    # Facing south, going west
+    assert(rail_env_trans.get_transition_from_orientation_to_direction(north_west_transition, 2, 3))
+
+    assert(south_east_transition == rail_env_trans.rotate_transition(south_east_transition, 360))
+
+
+def test_diagonal_transitions():
+    diagonal_trans_env = GridTransitions([], True)
+
+    # Facing north, going north-east
+    south_northeast_transition = int('01000000' + '0'*8*7, 2)
+    assert(diagonal_trans_env.get_transitions_from_orientation(south_northeast_transition, 0) ==
+           (0, 1, 0, 0, 0, 0, 0, 0))
+
+    # Allowing transition from north to southwest: Facing south, going southwest
+    north_southwest_transition = diagonal_trans_env.set_transitions_from_orientation(
+        int('0' *64, 2), 4, (0, 0, 0, 0, 0, 1, 0, 0))
+
+    assert(diagonal_trans_env.rotate_transition(south_northeast_transition, 180) == north_southwest_transition)
 
 
-def test_transition_example():
-    """Test example Transition."""
-    a = True
-    b = True
-    assert a == b