Added unit tests and fixed rotate_right() incorrect check for

is_initialized()

toyrobot/robot.py

@@ -259,8 +259,9 @@ class Robot:
         (initialized).
         """
 
-        if self.is_initialized():
+        if not self.is_initialized():
             return
+
         self._direction = (self._direction + 1) % 4
 
     def interpret_command(self, command: str):

trtests.py

@@ -0,0 +1,138 @@
+#!/usr/bin/env python3
+
+import unittest
+import toyrobot
+
+class ToyRobotTests(unittest.TestCase):
+
+    def test_creation(self):
+        robot = toyrobot.Robot()
+        self.assertFalse(robot.is_initialized())
+
+    def test_initialization(self):
+        robot = toyrobot.Robot()
+        robot.place(0, 0, "NORTH")
+        self.assertTrue(robot.is_initialized())
+
+    def test_invalid_max_x(self):
+        exception_thrown = False
+        try:
+            robot = toyrobot.Robot(-1, 5)
+        except ValueError as ve:
+            exception_thrown = True
+        self.assertTrue(exception_thrown)
+
+    def test_invalid_max_y(self):
+        exception_thrown = False
+        try:
+            robot = toyrobot.Robot(5, -1)
+        except ValueError as ve:
+            exception_thrown = True
+        self.assertTrue(exception_thrown)
+
+    def test_valid_place(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 1, "NORTH")
+        self.assertTrue(robot.is_initialized() and \
+            robot.get_position() == (1, 1) and \
+            robot.get_direction() == "NORTH")
+
+    def test_invalid_place_position_x(self):
+        robot = toyrobot.Robot()
+        robot.place(6, 1, "NORTH")
+        self.assertFalse(robot.is_initialized())
+
+    def test_invalid_place_position_y(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 6, "NORTH")
+        self.assertFalse(robot.is_initialized())
+
+    def test_invalid_place_position_both(self):
+        robot = toyrobot.Robot()
+        robot.place(6, 6, "NORTH")
+        self.assertFalse(robot.is_initialized())
+
+    def test_invalid_place_direction(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 1, "INVALID")
+        self.assertFalse(robot.is_initialized())
+
+    def test_missing_place_direction(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 1)
+        self.assertFalse(robot.is_initialized())
+
+    def test_double_place(self):
+        robot = toyrobot.Robot()
+        robot.place(5, 5, "NORTH")
+        robot.place(2, 2)
+        self.assertTrue(robot.is_initialized() and \
+            robot.get_position() == (2, 2) and \
+            robot.get_direction() == "NORTH")
+
+    def test_double_place_2(self):
+        robot = toyrobot.Robot()
+        robot.place(5, 5, "NORTH")
+        robot.place(2, 2, "SOUTH")
+        self.assertTrue(robot.is_initialized() and \
+            robot.get_position() == (2, 2) and \
+            robot.get_direction() == "SOUTH")
+
+    def test_valid_movement_x(self):
+        robot = toyrobot.Robot()
+        robot.place(2, 2, "EAST")
+        robot.move()
+        self.assertTrue(robot.get_position() == (3, 2))
+
+    def test_valid_movement_y(self):
+        robot = toyrobot.Robot()
+        robot.place(2, 2, "NORTH")
+        robot.move()
+        self.assertTrue(robot.get_position() == (2, 3))
+
+    def test_invalid_movement_north(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 5, "NORTH")
+        robot.move()
+        self.assertTrue(robot.get_position() == (1, 5))
+
+    def test_invalid_movement_east(self):
+        robot = toyrobot.Robot()
+        robot.place(5, 1, "EAST")
+        robot.move()
+        self.assertTrue(robot.get_position() == (5, 1))
+
+    def test_invalid_movement_south(self):
+        robot = toyrobot.Robot()
+        robot.place(1, 0, "SOUTH")
+        robot.move()
+        self.assertTrue(robot.get_position() == (1, 0))
+
+    def test_invalid_movement_west(self):
+        robot = toyrobot.Robot()
+        robot.place(0, 1, "WEST")
+        robot.move()
+        self.assertTrue(robot.get_position() == (0, 1))
+
+    def test_rotate_left(self):
+        robot = toyrobot.Robot()
+        robot.place(0, 0, "NORTH")
+        robot.rotate_left()
+        self.assertTrue(robot.get_direction() == "WEST")
+
+    def test_rotate_right(self):
+        robot = toyrobot.Robot()
+        robot.place(0, 0, "NORTH")
+        robot.rotate_right()
+        self.assertTrue(robot.get_direction() == "EAST")
+
+    def test_rotate_right_2(self):
+        # Blackbox test - ensures internal numerical direction using modulus
+        # correctly.
+        robot = toyrobot.Robot()
+        robot.place(0, 0, "WEST")
+        robot.rotate_right()
+        self.assertTrue(robot.get_direction() == "NORTH")
+
+if __name__ == '__main__':
+    unittest.main()