refactor tests to use context manager

[Remi-Gau]

Tests that check for errors or warnings and should use context manager.

Originally posted by @ymzayek in #3795 (comment)

Example:

This:

nilearn/nilearn/maskers/tests/test_multi_nifti_masker.py

Lines 26 to 32 in 8a7a80c

	# Check that if we have not fit the masker we get a intelligible
	# error
	pytest.raises(
	ValueError,
	masker.transform,
	[[img]],
	)

Should become:

    # Check that if we have not fit the masker we get a intelligible
    # error
    with pytest.raises(ValueError):
        masker.transform([[img]])

video intros to:

• pytest: https://www.youtube.com/watch?v=mzlH8lp4ISA
• test errors with pytest: https://www.youtube.com/watch?v=6nRxZyQwwlE

See pytest documentation for more information:

• https://docs.pytest.org/en/7.1.x/how-to/assert.html#assertions-about-expected-exceptions

list of files to to modify:

$ find nilearn -name '*.py' -exec grep -H "pytest.raises" {} \; | grep -v with

nilearn/datasets/tests/test_atlas.py:    pytest.raises(
nilearn/datasets/tests/test_atlas.py:    pytest.raises(ValueError, atlas.fetch_atlas_talairach, "bad_level")
nilearn/datasets/tests/test_atlas.py:    pytest.raises(ValueError, atlas.fetch_atlas_schaefer_2018, n_rois=44)
nilearn/datasets/tests/test_atlas.py:    pytest.raises(ValueError, atlas.fetch_atlas_schaefer_2018, yeo_networks=10)
nilearn/datasets/tests/test_atlas.py:    pytest.raises(ValueError, atlas.fetch_atlas_schaefer_2018, resolution_mm=3)
nilearn/datasets/tests/test_neurovault.py:    pytest.raises(requests.RequestException, neurovault._get_batch, "http://")
nilearn/datasets/tests/test_neurovault.py:        pytest.raises(
nilearn/datasets/tests/test_neurovault.py:    pytest.raises(ValueError, neurovault._get_batch, no_results_url)
nilearn/datasets/tests/test_neurovault.py:        pytest.raises(
nilearn/datasets/tests/test_neurovault.py:        pytest.raises(
nilearn/datasets/tests/test_neurovault.py:    pytest.raises(ValueError, neurovault.fetch_neurovault_ids, mode="bad")
nilearn/tests/test_signal.py:    pytest.raises(TypeError, nisignal.clean, x, low_pass=False)
nilearn/tests/test_signal.py:    pytest.raises(TypeError, nisignal.clean, x, high_pass=False)
nilearn/tests/test_signal.py:    pytest.raises(ValueError, clean, sx, low_pass=0.4, high_pass=0.5, t_r=2.5)
nilearn/tests/test_signal.py:    pytest.raises(TypeError, nisignal.clean, signals, confounds=1)
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals, confounds=np.zeros(2))
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals[:-1, :],
nilearn/tests/test_signal.py:    pytest.raises(TypeError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    error_msg = pytest.raises(ValueError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals, t_r=None,
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    pytest.raises(ValueError, nisignal.clean, signals,
nilearn/tests/test_signal.py:    pytest.raises(AssertionError, np.testing.assert_almost_equal,
nilearn/tests/test_masking.py:    pytest.raises(ValueError, compute_epi_mask, mean_image)
nilearn/tests/test_masking.py:    pytest.raises(ValueError, compute_background_mask, mean_image)
nilearn/tests/test_masking.py:    pytest.raises(ValueError, masking.apply_mask,
nilearn/tests/test_masking.py:    pytest.raises(ValueError, masking.apply_mask,
nilearn/tests/test_masking.py:    pytest.raises(ValueError, masking.apply_mask,
nilearn/tests/test_masking.py:    pytest.raises(ValueError, masking.apply_mask,
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, vec_1D, mask_img)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, [vec_1D], mask_img)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, vec_2D, mask_img)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, [vec_2D], mask_img)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, compute_multi_epi_mask, [])
nilearn/tests/test_masking.py:        pytest.raises(ValueError, compute_multi_epi_mask,
nilearn/tests/test_masking.py:    pytest.raises(TypeError, compute_multi_brain_mask, [])
nilearn/tests/test_masking.py:    pytest.raises(ValueError, compute_multi_brain_mask, imgs)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, X, mask_img)
nilearn/tests/test_masking.py:    pytest.raises(TypeError, unmask, X, mask_img)
nilearn/surface/tests/test_surface.py:    pytest.raises(ValueError, surface._sample_locations,
nilearn/surface/tests/test_surface.py:    pytest.raises(ValueError, surface._projection_matrix,
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.transform, fmri12_img)
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.transform, fmri21_img)
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:    pytest.raises(
nilearn/maskers/tests/test_multi_nifti_maps_masker.py:    pytest.raises(
nilearn/maskers/tests/test_multi_nifti_masker.py:    pytest.raises(
nilearn/maskers/tests/test_multi_nifti_masker.py:    pytest.raises(ValueError, masker.fit, img)
nilearn/maskers/tests/test_nifti_masker.py:        pytest.raises(TypeError, masker.fit)
nilearn/maskers/tests/test_nifti_masker.py:    pytest.raises(ValueError, masker.fit_transform, data_img)
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.transform, fmri12_img)
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.transform, fmri21_img)
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(
nilearn/maskers/tests/test_multi_nifti_labels_masker.py:    pytest.raises(
nilearn/maskers/tests/test_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.transform, fmri12_img)
nilearn/maskers/tests/test_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.transform, fmri21_img)
nilearn/maskers/tests/test_nifti_maps_masker.py:            pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_nifti_maps_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_nifti_maps_masker.py:    pytest.raises(ValueError, NiftiMapsMasker, maps33_img,
nilearn/maskers/tests/test_nifti_maps_masker.py:    pytest.raises(ValueError, NiftiMapsMasker, maps33_img,
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.transform, fmri12_img)
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.transform, fmri21_img)
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, masker11.fit)
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, NiftiLabelsMasker, labels33_img,
nilearn/maskers/tests/test_nifti_labels_masker.py:    pytest.raises(ValueError, NiftiLabelsMasker, labels33_img,
nilearn/_utils/tests/test_param_validation.py:                pytest.raises(
nilearn/_utils/tests/test_numpy_conversions.py:    pytest.raises(ValueError, as_ndarray, "test string")
nilearn/_utils/tests/test_numpy_conversions.py:    pytest.raises(ValueError, as_ndarray, [], order="invalid")
nilearn/_utils/tests/test_numpy_conversions.py:        pytest.raises(TypeError, csv_to_array, filename, delimiters="?!")
nilearn/_utils/tests/test_ndimage.py:    pytest.raises(ValueError, largest_connected_component, a)
nilearn/_utils/tests/test_ndimage.py:    pytest.raises(ValueError, largest_connected_component, img)
nilearn/_utils/tests/test_ndimage.py:    pytest.raises(ValueError, largest_connected_component, "Test String")
nilearn/plotting/tests/test_img_plotting/test_plot_stat_map.py:    pytest.raises(ValueError, plot_stat_map, testdata_3d_for_plotting['img'],
nilearn/plotting/tests/test_img_plotting/test_plot_anat.py:    pytest.raises(Exception, plot_anat, display_mode="zzz")
nilearn/regions/tests/test_rena_clustering.py:    pytest.raises(ValueError, rena.fit, X)
nilearn/regions/tests/test_rena_clustering.py:        pytest.raises(ValueError, rena.fit, X)

$ find nilearn -name '*.py' -exec grep -H "pytest.warns" {} \; | grep -v with

nilearn/tests/test_signal.py:    pytest.warns(UserWarning, nisignal.clean, signals,
nilearn/plotting/tests/test_html_document.py:    pytest.warns(UserWarning, _open_views)
nilearn/plotting/tests/test_html_document.py:    pytest.warns(UserWarning, _open_views)

[FrancoisPgm]

Hi, I'm happy to take care of this one :)

[Remi-Gau]

Hey.
Are you on site or remote?

[htwangtw]

François is here