[FIX] only download group maps when creating dataset and raise error …

…if no images are found for a contrast (#580)

* only download group maps

* fix and test case where no images are found for a contrast

* fix indent

* run black

nimare/io.py

@@ -505,13 +505,16 @@ def convert_neurovault_to_dataset(
             }
 
             sample_sizes = []
+            no_images = True
             for img_dict in images["results"]:
                 if not (
                     re.match(contrast_regex, img_dict["name"])
                     and img_dict["map_type"] in map_type_conversion
+                    and img_dict["analysis_level"] == "group"
                 ):
                     continue
 
+                no_images = False
                 filename = img_dir / (
                     f"collection-{nv_coll}_id-{img_dict['id']}_" + Path(img_dict["file"]).name
                 )
@@ -530,6 +533,11 @@ def convert_neurovault_to_dataset(
                 # aggregate sample sizes (should all be the same)
                 sample_sizes.append(img_dict["number_of_subjects"])
 
+            if no_images:
+                raise ValueError(
+                    f"No images were found for contrast {contrast_name}. "
+                    f"Please check the contrast regular expression: {contrast_regex}"
+                )
             # take modal sample size (raise warning if there are multiple values)
             if len(set(sample_sizes)) > 1:
                 sample_size = _resolve_sample_size(sample_sizes)

nimare/tests/test_io.py

@@ -168,6 +168,19 @@ def test_convert_neurosynth_to_json_smoke():
                 "map_type_conversion": {"univariate-beta map": "beta"},
             }
         ),
+        (
+            {
+                "collection_ids": (11303,),
+                "contrasts": {"rms": "rms"},
+                "map_type_conversion": {"univariate-beta map": "beta"},
+            }
+        ),
+        (
+            {
+                "collection_ids": (8836,),
+                "contrasts": {"crab_people": "cannot hurt you because they do not exist"},
+            }
+        ),
     ],
 )
 def test_convert_neurovault_to_dataset(kwargs):
@@ -177,6 +190,11 @@ def test_convert_neurovault_to_dataset(kwargs):
             dset = io.convert_neurovault_to_dataset(**kwargs)
         assert "Collection 778 not found." in str(excinfo.value)
         return
+    elif "crab_people" in kwargs["contrasts"].keys():
+        with pytest.raises(ValueError) as excinfo:
+            dset = io.convert_neurovault_to_dataset(**kwargs)
+        assert "No images were found for contrast crab_people" in str(excinfo.value)
+        return
     else:
         dset = io.convert_neurovault_to_dataset(**kwargs)