Function test_draw

lib/matplotlib/tests/test_backend_bases.py:333–360

(backend)

                pytest.param('pgf', marks=needs_pgf_xelatex)]
)
def test_draw(backend):
    from matplotlib.figure import Figure
    from matplotlib.backends.backend_agg import FigureCanvas
    test_backend = importlib.import_module(f'matplotlib.backends.backend_{backend}')
    TestCanvas = test_backend.FigureCanvas
    fig_test = Figure(constrained_layout=True)
    TestCanvas(fig_test)
    axes_test = fig_test.subplots(2, 2)

    # defaults to FigureCanvasBase
    fig_agg = Figure(constrained_layout=True)
    # put a backends.backend_agg.FigureCanvas on it
    FigureCanvas(fig_agg)
    axes_agg = fig_agg.subplots(2, 2)

    init_pos = [ax.get_position() for ax in axes_test.ravel()]

    fig_test.canvas.draw()
    fig_agg.canvas.draw()

    layed_out_pos_test = [ax.get_position() for ax in axes_test.ravel()]
    layed_out_pos_agg = [ax.get_position() for ax in axes_agg.ravel()]

    for init, placed in zip(init_pos, layed_out_pos_test):
        assert not np.allclose(init, placed, atol=0.005)

    for ref, test in zip(layed_out_pos_agg, layed_out_pos_test):
        np.testing.assert_allclose(ref, test, atol=0.005)


@pytest.mark.parametrize(