def test_get_constant_value_non_constant(self):
"""get_constant_value return None on non-constant arrays."""
# Setup
X = np.array(range(5))
expected_result = None
# Run
result = Univariate._get_constant_value(X)
# Check
assert result is expected_result
def test_get_constant_value(self):
"""get_constant_value return the unique value of an array if it exists."""
# Setup
X = np.array([1, 1, 1, 1])
expected_result = 1
# Run
result = Univariate._get_constant_value(X)
# Check
assert result == expected_result
