Fix strategy bad input tests

Because all the calls in this test were expected to raise an error,
after the first one, none of the others were even tried. This makes each
failing call a separate test.

Author: pganssle

tests/test_strategies.py

@@ -60,10 +60,13 @@ def test_square_strategy(square_strategy, num_plots, grid_arrangement):
 
 
 # Test for bad input
-def test_strategy_with_bad_input(rectangular_strategy, square_strategy):
+@pytest.mark.parametrize("n", [-1, -1000])
+def test_rectangular_strategy_with_bad_input(rectangular_strategy, n):
     with pytest.raises(ValueError):
-        rectangular_strategy.get_grid(-1)
-        rectangular_strategy.get_grid(-1000)
+        rectangular_strategy.get_grid(n)
 
-        square_strategy.get_grid(-1)
-        square_strategy.get_grid(-110)
+
+@pytest.mark.parametrize("n", [-1, -1000])
+def test_square_strategy_with_bad_input(square_strategy, n):
+    with pytest.raises(ValueError):
+        square_strategy.get_grid(n)