Adding example of string converter in SelectFiles

Author: mwaskom

nipype/interfaces/io.py

@@ -588,6 +588,13 @@ class SelectFiles(IOBase):
     >>> dg.outputs.get()
     {'T1': <undefined>, 'epi': <undefined>}
 
+    The same thing with dynamic grabbing of specific files:
+
+    >>> templates["epi"] = "{subject_id}/func/f{run!s}.nii"
+    >>> dg = Node(SelectFiles(templates), "selectfiles")
+    >>> dg.inputs.subject_id = "subj1"
+    >>> dg.inputs.run = [2, 4]
+
     """
     input_spec = SelectFilesInputSpec
     output_spec = DynamicTraitedSpec

nipype/interfaces/tests/test_io.py

@@ -42,6 +42,13 @@ def test_selectfiles():
                      "interfaces/spm/preprocess.py")
     yield assert_equal, res.outputs.preprocess, [wanted]
 
+    templates = {"converter": "interfaces/dcm{to!s}nii.py"}
+    dg = nio.SelectFiles(templates, base_directory=base_dir)
+    dg.inputs.to = 2
+    res = dg.run()
+    wanted = op.join(base_dir, "interfaces/dcm2nii.py")
+    yield assert_equal, res.outputs.converter, wanted
+
 
 def test_datasink():
     ds = nio.DataSink()