use double slash to test local relative instead

snakebids/core/input_generation.py

@@ -15,7 +15,6 @@
     Literal,
     overload,
 )
-from urllib.parse import urlparse
 
 import more_itertools as itx
 from bids import BIDSLayout, BIDSLayoutIndexer
@@ -393,26 +392,22 @@ def _all_custom_paths(config: InputsConfig):
     return all(comp.get("custom_path") for comp in config.values())
 
 
-def _is_network_fs_path(path: Path | str):
-    """Test if a path location is using a network file system e.g. "gs://" or "s3://".
-
-    Paths like "file:///..." will not be recognized as network even if they may be
-    network locations mapped to a local location. Windows ("C://") and linux
-    ("/path/to/file") paths and relative path ("path/to/file") are not network file
-    system paths.
+def _is_local_relative(path: Path | str):
+    """Test if a path location is local path relative to the current working directory.
 
     Parameter
     ---------
-        A UPath, Path, or str object to be checked
+        path
+            A UPath, Path, or str object to be checked
 
     Returns
     -------
     is_url : bool
-        True if the path belongs to a network file system
+        True if the path is relative
     """
-    # StackOverflow reference: (by Kukanani)
-    # https://stackoverflow.com/questions/8357098/how-can-i-check-if-a-url-is-absolute-using-python
-    return bool(urlparse(str(path)).netloc)  # netloc="" for non-local paths
+    path_str = str(path)
+    is_doubleslash_schemed = "://" in path_str
+    return not is_doubleslash_schemed and not os.path.isabs(path_str)
 
 
 def _gen_bids_layout(
@@ -746,11 +741,7 @@ def _parse_bids_path(path: str, entities: Iterable[str]) -> tuple[str, dict[str,
     # If path is relative, we need to get a slash in front of it to ensure parsing works
     # correctly. So prepend "./" or ".\" and run function again, then strip before
     # returning
-    if (
-        not _is_network_fs_path(path)
-        and not os.path.isabs(path)
-        and get_first_dir(path) != "."
-    ):
+    if _is_local_relative(path) and get_first_dir(path) != ".":
         path_, wildcard_values = _parse_bids_path(os.path.join(".", path), entities)
         return str(Path(path_)), wildcard_values
 

snakebids/tests/strategies.py

@@ -37,6 +37,11 @@
 valid_entities: tuple[str, ...] = tuple(BidsConfig.load("bids").entities.keys())
 
 path_characters = st.characters(blacklist_characters=["/", "\x00"], codec="UTF-8")
+# StackOverflow answer by Gumbo
+# https://stackoverflow.com/questions/1547899/which-characters-make-a-url-invalid#1547940
+scheme_characters = st.sampled_from(
+    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789-._~?#[]@!$&'()*+,;="
+)
 
 
 def nothing() -> Any:
@@ -45,15 +50,9 @@ def nothing() -> Any:
 
 def schemes() -> st.SearchStrategy[str]:
     # Generate the prefix part of a url.
-    #
-    # we only sample from a fixed set of schemes. If schemes are randomly generated
-    # then something like file:// could be a problem because it may be either an
-    # abs or relative path and will fail the os.path.isabs() code
-    #
-    # Note for its current status we don't guarantee the following schemes to work
-    # but only requiring them to be retained correctly i.e. not from 'gs://' to
-    # 'gs:/' when fed into generate_inputs() and path expansion
-    return st.sampled_from(["C://", "c:\\", "gs://", "s3://"])
+    random_st = st.text(scheme_characters, min_size=1).map(lambda s: f"{s}://")
+    fixed_st = st.sampled_from(["C://", "c:\\", "gs://", "s3://"])
+    return random_st | fixed_st
 
 
 def paths(

snakebids/tests/test_generate_inputs.py

@@ -30,7 +30,7 @@
     _all_custom_paths,
     _gen_bids_layout,
     _get_components,
-    _is_network_fs_path,
+    _is_local_relative,
     _normalize_database_args,
     _parse_bids_path,
     _parse_custom_path,
@@ -1611,23 +1611,21 @@ class TestRecogPathSchemes:
         ("./hello/world", "RELATIVE"),
         ("hello/world", "RELATIVE"),
         ("/hello/world", "ABSOLUTE"),
-        (r"C:\some\file", "ABSOLUTE"),
-        (r"C:\\some\\file", "ABSOLUTE"),
-        ("C:/some/file", "ABSOLUTE"),
         ("gs://some/google/cloud/bucket", "NETWORK"),
         ("s3://some/s3/bucket", "NETWORK"),
     )
 
     @pytest.mark.parametrize(("path", "path_type"), PATH_AND_TYPES)
-    def test_is_network_fs_path(self, path, path_type):
+    def test_is_local_relative(self, path, path_type):
         isnet = path_type == "NETWORK"
+        is_local_relative = path_type == "RELATIVE"
 
         # test the path itself, and the corresponding Path(path)
         assert (
-            _is_network_fs_path(path) == isnet
-        ), f"Path {path} should have isnet={isnet} but got {_is_network_fs_path(path)}"
+            _is_local_relative(path) == is_local_relative
+        ), f"Path {path} fails is local relative path test."
         if not isnet:
-            assert not _is_network_fs_path(Path(path))
+            assert _is_local_relative(Path(path)) == is_local_relative
 
     @pytest.mark.skipif(
         sys.version_info < (3, 12), reason="Path class has no with_segments()"
@@ -1645,7 +1643,7 @@ def __init__(self, *pathsegments):
             def __str__(self):  # __fspath__ calls __str__ by default
                 return f"gs://{super().__str__()}"
 
-        assert _is_network_fs_path(MockGCSPath(path))
+        assert not _is_local_relative(MockGCSPath(path))
 
 
 @example_if(
@@ -1914,7 +1912,7 @@ def test_when_all_custom_paths_no_layout_indexed(
 class TestParseBidsPath:
     @given(
         component=sb_st.bids_components(max_values=1, restrict_patterns=True),
-        scheme=sb_st.schemes(),
+        scheme=sb_st.schemes() | st.none(),
     )
     def test_splits_wildcards_from_path(
         self, component: BidsComponent, scheme: str | None
@@ -1928,7 +1926,7 @@ def test_splits_wildcards_from_path(
 
     @given(
         component=sb_st.bids_components(max_values=1, restrict_patterns=True),
-        scheme=sb_st.schemes(),
+        scheme=sb_st.schemes() | st.none(),
     )
     def test_one_match_found_for_each_entity(
         self, component: BidsComponent, scheme: str | None
@@ -1946,7 +1944,7 @@ def test_one_match_found_for_each_entity(
         component=sb_st.bids_components(
             max_values=1, restrict_patterns=True, extra_entities=False
         ),
-        scheme=sb_st.schemes(),
+        scheme=sb_st.schemes() | st.none(),
         entity=sb_st.bids_entity(),
     )
     def test_missing_match_leads_to_error(