Raise if get_map can't find any maps instead of logging and returning None

.github/workflows/siibra-testing.yml

@@ -70,7 +70,7 @@ jobs:
         python-version: ["3.12", "3.11", "3.10", "3.9", "3.8", "3.7"]
 
   unit-tests-fast:
-    if: ${{ github.event_name != 'pull_request' }}
+    if: ${{ github.event.pull_request == null }}
     needs: "use-custom-cfg"
     uses: ./.github/workflows/_unittest.yaml
     with:
@@ -92,7 +92,7 @@ jobs:
         python-version: ["3.12", "3.11", "3.10", "3.9", "3.8", "3.7"]
 
   e2e-tests-fast:
-    if: ${{ github.event_name != 'pull_request' }}
+    if: ${{ github.event.pull_request == null }}
     needs: "use-custom-cfg"
     uses: ./.github/workflows/_e2e.yaml
     with:

siibra/core/parcellation.py

@@ -17,11 +17,20 @@
 
 from ..commons import logger, MapType, Species
 from ..volumes import parcellationmap
+from ..exceptions import NoMapMatchingValues
 
-from typing import Union, List, Dict
 import re
+from typing import Union, List, Dict, TYPE_CHECKING
+try:
+    from typing import Literal
+except ImportError:
+    # support python 3.7
+    from typing_extensions import Literal
 
 
+if TYPE_CHECKING:
+    from .space import Space
+
 # NOTE : such code could be used to automatically resolve
 # multiple matching parcellations for a short spec to the newset version:
 #               try:
@@ -140,7 +149,12 @@
                     self._CACHED_MATCHES[spec] = True
         return super().matches(spec)
 
-    def get_map(self, space=None, maptype: Union[str, MapType] = MapType.LABELLED, spec: str = ""):
+    def get_map(
+        self,
+        space: Union[str, "Space"],
+        maptype: Union[Literal['labelled', 'statistical'], MapType] = MapType.LABELLED,
+        spec: str = ""
+    ):
         """
         Get the maps for the parcellation in the requested template space.
 
@@ -153,8 +167,8 @@
         Parameters
         ----------
         space: Space or str
-            template space specification
-        maptype: MapType
+            reference space specification such as name, id, or a `Space` instance.
+        maptype: MapType or str
             Type of map requested (e.g., statistical or labelled).
             Use MapType.STATISTICAL to request probability maps.
             Defaults to MapType.LABELLED.
@@ -169,26 +183,24 @@
             A ParcellationMap representing the volumetric map or
             a SparseMap representing the list of statistical maps.
         """
-        if not isinstance(maptype, MapType):
+        if isinstance(maptype, str):
             maptype = MapType[maptype.upper()]
+        assert isinstance(maptype, MapType), "Possible values of `maptype` are `MapType`s, 'labelled', 'statistical'."
 
         candidates = [
             m for m in parcellationmap.Map.registry()
             if m.space.matches(space)
             and m.maptype == maptype
-            and m.parcellation
             and m.parcellation.matches(self)
         ]
         if len(candidates) == 0:
-            logger.error(f"No {maptype} map in {space} available for {str(self)}")
-            return None
+            raise NoMapMatchingValues(f"No '{maptype}' map in '{space}' available for {str(self)}")
         if len(candidates) > 1:
             spec_candidates = [
                 c for c in candidates if all(w.lower() in c.name.lower() for w in spec.split())
             ]
             if len(spec_candidates) == 0:
-                logger.warning(f"'{spec}' does not match any options from {[c.name for c in candidates]}.")
-                return None
+                raise NoMapMatchingValues(f"'{spec}' does not match any options from {[c.name for c in candidates]}.")
             if len(spec_candidates) > 1:
                 logger.warning(
                     f"Multiple maps are available in this specification of space, parcellation, and map type.\n"

siibra/exceptions.py

@@ -53,3 +53,7 @@ class ZeroVolumeBoundingBox(Exception):
 
 class NoneCoordinateSuppliedError(ValueError):
     pass
+
+
+class NoMapMatchingValues(ValueError):
+    pass

test/core/test_parcellation.py

@@ -11,6 +11,7 @@
 from siibra.core.region import Region
 from siibra.commons import Species
 import siibra
+from siibra.exceptions import NoMapMatchingValues
 
 correct_json = {
     "name": "foobar",
@@ -82,7 +83,7 @@ def test_attr(self):
 INCORRECT_MAP_TYPE = "incorrect_type"
 
 
-class InputMap(NamedTuple):
+class InputMapType(NamedTuple):
     input: Union[str, MapType]
     alias: MapType
 
@@ -121,10 +122,11 @@ def setUpClass(cls) -> None:
             [None, "space arg", DummySpace()],
             # input, maptype
             [
-                InputMap(None, MapType.LABELLED),
-                InputMap("labelled", MapType.LABELLED),
-                InputMap(MapType.LABELLED, MapType.LABELLED),
-                InputMap(INCORRECT_MAP_TYPE, None),
+                InputMapType(None, None),
+                InputMapType("labelled", MapType.LABELLED),
+                InputMapType("Laballlled", None),
+                InputMapType(MapType.LABELLED, MapType.LABELLED),
+                InputMapType(INCORRECT_MAP_TYPE, None),
             ],
             # volume configuration
             product(
@@ -148,12 +150,11 @@ def setUpClass(cls) -> None:
         )
     )
     def test_get_map(
-        self, space, maptype_input: InputMap, vol_spec: Tuple[MapConfig, MapConfig]
+        self, space, maptype_input: InputMapType, vol_spec: Tuple[MapConfig, MapConfig]
     ):
         from siibra.volumes import Map
 
         ExpectedException = None
-        expected_return_idx = None
 
         for idx, vol_s in enumerate(vol_spec):
             if (
@@ -163,9 +164,11 @@ def test_get_map(
             ):
                 expected_return_idx = idx
                 break
+        else:
+            ExpectedException = NoMapMatchingValues
 
         if maptype_input.alias is None:
-            ExpectedException = KeyError
+            ExpectedException = AssertionError if maptype_input.input is None else KeyError
 
         with patch.object(Map, "registry") as map_registry_mock:
             registry_return = [
@@ -196,7 +199,7 @@ def test_get_map(
             if expected_return_idx is not None:
                 self.assertIs(map, registry_return[expected_return_idx])
             else:
-                self.assertIsNone(map)
+                self.assertRaises(ExpectedException)
 
     @parameterized.expand(
         [