ENH: add test for PET confounds workflow

Author: mnoergaard

fmriprep/workflows/pet/tests/test_confounds.py

@@ -0,0 +1,34 @@
+import nibabel as nb
+import numpy as np
+
+from ..confounds import init_pet_confs_wf
+
+
+def test_dvars_connects_pet_mask(tmp_path):
+    """Check dvars node connection and execution."""
+    wf = init_pet_confs_wf(
+        mem_gb=0.01,
+        metadata={},
+        regressors_all_comps=False,
+        regressors_dvars_th=1.5,
+        regressors_fd_th=0.5,
+    )
+
+    edge = wf._graph.get_edge_data(wf.get_node('inputnode'), wf.get_node('dvars'))
+    assert ('pet_mask', 'in_mask') in edge['connect']
+
+    img = nb.Nifti1Image(np.random.rand(2, 2, 2, 5), np.eye(4))
+    mask = nb.Nifti1Image(np.ones((2, 2, 2), dtype=np.uint8), np.eye(4))
+    pet_file = tmp_path / 'pet.nii.gz'
+    mask_file = tmp_path / 'mask.nii.gz'
+    img.to_filename(pet_file)
+    mask.to_filename(mask_file)
+
+    node = wf.get_node('dvars')
+    node.base_dir = tmp_path
+    node.inputs.in_file = str(pet_file)
+    node.inputs.in_mask = str(mask_file)
+    result = node.run()
+
+    assert result.outputs.out_nstd
+    assert result.outputs.out_std