Repository: matplotlib/matplotlib
File: lib/matplotlib/tests/test_axes.py (Python)

Code before:
    match="datetime/date 'position' values, require timedelta 'widths'"):
        ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_numeric_positions_with_float_widths_ok():
    """Test that numeric positions with float widths work."""
    fig, ax = plt.subplots()
    positions = [1.0, 2.0]
    widths = [0.5, 1.0]
    ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_mixed_positions_datetime_and_numeric_behaves():
    """Test that mixed datetime and numeric positions
    with float widths raise TypeError.
    """
    fig, ax = plt.subplots()
    positions = [datetime.datetime(2020, 1, 1), 2.0]
    widths = [0.5, 1.0]
    with pytest.raises(TypeError,
    match="datetime/date 'position' values, require timedelta 'widths'"):
        ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_violinplot_bad_positions():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(47))
    np.random.seed(855654600)
    data = [np.random.normal(size=100) for _ in range(4)]
    with pytest.raises(ValueError):
        ax.violinplot(data, positions=range(5))


def test_violinplot_bad_widths():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(53))
    np.random.seed(280109889)
    data = [np.random.normal(size=100) for _ in range(4)]
    with pytest.raises(ValueError):
        ax.violinplot(data, positions=range(4), widths=[1, 2, 3])


def test_violinplot_bad_quantiles():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(73))
    np.random.seed(544003745)
    data = [np.random.normal(size=100)]

    # Different size quantile list and plots
    with pytest.raises(ValueError):
        ax.violinplot(data, quantiles=[[0.1, 0.2], [0.5, 0.7]])

Review comment (bug):
While these tests verify that incorrect combinations of datetime positions with float widths raise errors, there's no test for the successful case where datetime positions are paired with timedelta widths (or np.datetime64 with np.timedelta64). Add positive test cases to ensure that the correct usage actually works and doesn't raise an error, similar to test_numeric_positions_with_float_widths_ok.

Code after:
    widths = 0.75
    with pytest.raises(TypeError,
                       match=("datetime/date 'position' values require "
                              "timedelta 'widths'")):
        ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_numeric_positions_with_float_widths_ok():
    """Test that numeric positions with float widths work."""
    fig, ax = plt.subplots()
    positions = [1.0, 2.0]
    widths = [0.5, 1.0]
    ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_mixed_positions_datetime_and_numeric_raises():
    """Test that mixed datetime and numeric positions
    with float widths raise TypeError.
    """
    fig, ax = plt.subplots()
    positions = [datetime.datetime(2020, 1, 1), 2.0]
    widths = [0.5, 1.0]
    with pytest.raises(TypeError,
                       match=("datetime/date 'position' values require "
                              "timedelta 'widths'")):
        ax.violin(violin_plot_stats(), positions=positions, widths=widths)


def test_violinplot_bad_positions():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(47))
    np.random.seed(855654600)
    data = [np.random.normal(size=100) for _ in range(4)]
    with pytest.raises(ValueError):
        ax.violinplot(data, positions=range(5))


def test_violinplot_bad_widths():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(53))
    np.random.seed(280109889)
    data = [np.random.normal(size=100) for _ in range(4)]
    with pytest.raises(ValueError):
        ax.violinplot(data, positions=range(4), widths=[1, 2, 3])


def test_violinplot_bad_quantiles():
    ax = plt.axes()
    # First 9 digits of frac(sqrt(73))
    np.random.seed(544003745)
    data = [np.random.normal(size=100)]