Add property testing example using hypothesis library

pyproject.toml

@@ -39,7 +39,8 @@ tests = [
     "pytest-randomly",
     "pytest-qt",
     "pytest-xvfb",
-    "ipytest"
+    "ipytest",
+    "hypothesis",
 ]
 
 # Command line scripts installed as part of the installation

tests/test_board.py

@@ -3,11 +3,23 @@
 from effective_software_testing.board import Board
 import pytest
 import numpy as np
+from hypothesis import given, assume, example
+from hypothesis.strategies import integers
 
 board_sizes = [1, 2, 3, 4, 5]
 players = [player for player in Player]
 
 
+@pytest.mark.parametrize("n", board_sizes)
+@given(x=integers(0, 99), y=integers(0, 99))
+@example(x=0, y=1)
+def test_hypothesis_empty_board_is_empty(n: int, x: int, y: int) -> None:
+    assume(x < n)
+    assume(y < n)
+    board = Board(n)
+    assert board.square(x, y) is None
+
+
 @pytest.mark.parametrize("n", board_sizes)
 def test_empty_board_is_empty(n: int) -> None:
     board = Board(n)