LocalFileSystem fix _strip_protocol for root directory (fsspec#1477)

Author: fleming79

fsspec/implementations/local.py

@@ -3,7 +3,6 @@
 import logging
 import os
 import os.path as osp
-import re
 import shutil
 import stat
 import tempfile
@@ -16,6 +15,12 @@
 logger = logging.getLogger("fsspec.local")
 
 
+def _remove_prefix(text: str, prefix: str):
+    if text.startswith(prefix):
+        return text[len(prefix) :]
+    return text
+
+
 class LocalFileSystem(AbstractFileSystem):
     """Interface to files on local storage
 
@@ -116,8 +121,8 @@ def lexists(self, path, **kwargs):
         return osp.lexists(path)
 
     def cp_file(self, path1, path2, **kwargs):
-        path1 = self._strip_protocol(path1).rstrip("/")
-        path2 = self._strip_protocol(path2).rstrip("/")
+        path1 = self._strip_protocol(path1, remove_trailing_slash=True)
+        path2 = self._strip_protocol(path2, remove_trailing_slash=True)
         if self.auto_mkdir:
             self.makedirs(self._parent(path2), exist_ok=True)
         if self.isfile(path1):
@@ -138,8 +143,8 @@ def put_file(self, path1, path2, callback=None, **kwargs):
         return self.cp_file(path1, path2, **kwargs)
 
     def mv_file(self, path1, path2, **kwargs):
-        path1 = self._strip_protocol(path1).rstrip("/")
-        path2 = self._strip_protocol(path2).rstrip("/")
+        path1 = self._strip_protocol(path1, remove_trailing_slash=True)
+        path2 = self._strip_protocol(path2, remove_trailing_slash=True)
         shutil.move(path1, path2)
 
     def link(self, src, dst, **kwargs):
@@ -163,7 +168,7 @@ def rm(self, path, recursive=False, maxdepth=None):
             path = [path]
 
         for p in path:
-            p = self._strip_protocol(p).rstrip("/")
+            p = self._strip_protocol(p, remove_trailing_slash=True)
             if self.isdir(p):
                 if not recursive:
                     raise ValueError("Cannot delete directory, set recursive=True")
@@ -206,24 +211,32 @@ def modified(self, path):
 
     @classmethod
     def _parent(cls, path):
-        path = cls._strip_protocol(path).rstrip("/")
-        if "/" in path:
-            return path.rsplit("/", 1)[0]
+        path = cls._strip_protocol(path, remove_trailing_slash=True)
+        if os.sep == "/":
+            # posix native
+            return path.rsplit("/", 1)[0] or "/"
         else:
-            return cls.root_marker
+            # NT
+            path_ = path.rsplit("/", 1)[0]
+            if len(path_) <= 3:
+                if path_[1:2] == ":":
+                    # nt root (something like c:/)
+                    return path_[0] + ":/"
+            # More cases may be required here
+            return path_
 
     @classmethod
-    def _strip_protocol(cls, path):
+    def _strip_protocol(cls, path, remove_trailing_slash=False):
         path = stringify_path(path)
-        if path.startswith("file://"):
-            path = path[7:]
-        elif path.startswith("file:"):
-            path = path[5:]
-        elif path.startswith("local://"):
-            path = path[8:]
+        if path.startswith("file:"):
+            path = _remove_prefix(_remove_prefix(path, "file://"), "file:")
+            if os.sep == "\\":
+                path = path.lstrip("/")
         elif path.startswith("local:"):
-            path = path[6:]
-        return make_path_posix(path).rstrip("/") or cls.root_marker
+            path = _remove_prefix(_remove_prefix(path, "local://"), "local:")
+            if os.sep == "\\":
+                path = path.lstrip("/")
+        return make_path_posix(path, remove_trailing_slash)
 
     def _isfilestore(self):
         # Inheriting from DaskFileSystem makes this False (S3, etc. were)
@@ -236,47 +249,42 @@ def chmod(self, path, mode):
         return os.chmod(path, mode)
 
 
-def make_path_posix(path, sep=os.sep):
-    """Make path generic"""
-    if isinstance(path, (list, set, tuple)):
-        return type(path)(make_path_posix(p) for p in path)
-    if "~" in path:
-        path = osp.expanduser(path)
-    if sep == "/":
-        # most common fast case for posix
+def make_path_posix(path, remove_trailing_slash=False):
+    """Make path generic for current OS"""
+    if not isinstance(path, str):
+        if isinstance(path, (list, set, tuple)):
+            return type(path)(make_path_posix(p, remove_trailing_slash) for p in path)
+        else:
+            path = str(stringify_path(path))
+    if os.sep == "/":
+        # Native posix
         if path.startswith("/"):
-            return path
-        if path.startswith("./"):
+            # most common fast case for posix
+            return path.rstrip("/") or "/" if remove_trailing_slash else path
+        elif path.startswith("~"):
+            return make_path_posix(osp.expanduser(path), remove_trailing_slash)
+        elif path.startswith("./"):
             path = path[2:]
+            path = f"{os.getcwd()}/{path}"
+            return path.rstrip("/") or "/" if remove_trailing_slash else path
         return f"{os.getcwd()}/{path}"
-    if (
-        (sep not in path and "/" not in path)
-        or (sep == "/" and not path.startswith("/"))
-        or (sep == "\\" and ":" not in path and not path.startswith("\\\\"))
-    ):
-        # relative path like "path" or "rel\\path" (win) or rel/path"
-        if os.sep == "\\":
-            # abspath made some more '\\' separators
-            return make_path_posix(osp.abspath(path))
-        else:
-            return f"{os.getcwd()}/{path}"
-    if path.startswith("file://"):
-        path = path[7:]
-    if re.match("/[A-Za-z]:", path):
-        # for windows file URI like "file:///C:/folder/file"
-        # or "file:///C:\\dir\\file"
-        path = path[1:].replace("\\", "/").replace("//", "/")
-    if path.startswith("\\\\"):
-        # special case for windows UNC/DFS-style paths, do nothing,
-        # just flip the slashes around (case below does not work!)
-        return path.replace("\\", "/")
-    if re.match("[A-Za-z]:", path):
-        # windows full path like "C:\\local\\path"
-        return path.lstrip("\\").replace("\\", "/").replace("//", "/")
-    if path.startswith("\\"):
-        # windows network path like "\\server\\path"
-        return "/" + path.lstrip("\\").replace("\\", "/").replace("//", "/")
-    return path
+    else:
+        # NT handling
+        if len(path) > 1:
+            if path[1] == ":":
+                # windows full path like "C:\\local\\path"
+                if len(path) <= 3:
+                    # nt root (something like c:/)
+                    return path[0] + ":/"
+                path = path.replace("\\", "/").replace("//", "/")
+                return path.rstrip("/") if remove_trailing_slash else path
+            elif path[0] == "~":
+                return make_path_posix(osp.expanduser(path), remove_trailing_slash)
+            elif path.startswith(("\\\\", "//")):
+                # windows UNC/DFS-style paths
+                path = "//" + path[2:].replace("\\", "/").replace("//", "/")
+                return path.rstrip("/") if remove_trailing_slash else path
+        return make_path_posix(osp.abspath(path), remove_trailing_slash)
 
 
 def trailing_sep(path):

fsspec/implementations/tests/test_jupyter.py

@@ -13,11 +13,10 @@
 
 @pytest.fixture()
 def jupyter(tmpdir):
-
     tmpdir = str(tmpdir)
     os.environ["JUPYTER_TOKEN"] = "blah"
     try:
-        cmd = f"jupyter notebook --notebook-dir={tmpdir} --no-browser --port=5566"
+        cmd = f'jupyter notebook --notebook-dir="{tmpdir}" --no-browser --port=5566'
         P = subprocess.Popen(shlex.split(cmd))
     except FileNotFoundError:
         pytest.skip("notebook not installed correctly")

fsspec/implementations/tests/test_local.py

@@ -472,33 +472,48 @@ def test_make_path_posix():
         drive = cwd[0]
         assert make_path_posix("/a/posix/path") == f"{drive}:/a/posix/path"
         assert make_path_posix("/posix") == f"{drive}:/posix"
+        # Windows drive requires trailing slash
+        assert make_path_posix("C:\\") == "C:/"
+        assert make_path_posix("C:\\", remove_trailing_slash=True) == "C:/"
     else:
         assert make_path_posix("/a/posix/path") == "/a/posix/path"
         assert make_path_posix("/posix") == "/posix"
     assert make_path_posix("relpath") == posixpath.join(make_path_posix(cwd), "relpath")
     assert make_path_posix("rel/path") == posixpath.join(
         make_path_posix(cwd), "rel/path"
     )
+    # NT style
     if WIN:
         assert make_path_posix("C:\\path") == "C:/path"
-        assert make_path_posix("file://C:\\path\\file") == "C:/path/file"
-    if WIN:
         assert (
             make_path_posix(
-                "\\\\windows-server\\someshare\\path\\more\\path\\dir\\foo.parquet"
+                "\\\\windows-server\\someshare\\path\\more\\path\\dir\\foo.parquet",
             )
             == "//windows-server/someshare/path/more/path/dir/foo.parquet"
         )
         assert (
             make_path_posix(
-                r"\\SERVER\UserHomeFolder$\me\My Documents\project1\data\filen.csv"
+                "\\\\SERVER\\UserHomeFolder$\\me\\My Documents\\proj\\data\\fname.csv",
             )
-            == "//SERVER/UserHomeFolder$/me/My Documents/project1/data/filen.csv"
+            == "//SERVER/UserHomeFolder$/me/My Documents/proj/data/fname.csv"
         )
     assert "/" in make_path_posix("rel\\path")
-
+    # Relative
     pp = make_path_posix("./path")
-    assert "./" not in pp and ".\\" not in pp
+    cd = make_path_posix(cwd)
+    assert pp == cd + "/path"
+    # Userpath
+    userpath = make_path_posix("~/path")
+    assert userpath.endswith("/path")
+
+
+def test_parent():
+    if WIN:
+        assert LocalFileSystem._parent("C:\\file or folder") == "C:/"
+        assert LocalFileSystem._parent("C:\\") == "C:/"
+    else:
+        assert LocalFileSystem._parent("/file or folder") == "/"
+        assert LocalFileSystem._parent("/") == "/"
 
 
 def test_linked_files(tmpdir):
@@ -638,16 +653,22 @@ def test_strip_protocol_expanduser():
     path = "file://~\\foo\\bar" if WIN else "file://~/foo/bar"
     stripped = LocalFileSystem._strip_protocol(path)
     assert path != stripped
+    assert "~" not in stripped
     assert "file://" not in stripped
     assert stripped.startswith(os.path.expanduser("~").replace("\\", "/"))
-    assert not LocalFileSystem._strip_protocol("./").endswith("/")
+    path = LocalFileSystem._strip_protocol("./", remove_trailing_slash=True)
+    assert not path.endswith("/")
 
 
 def test_strip_protocol_no_authority():
     path = "file:\\foo\\bar" if WIN else "file:/foo/bar"
     stripped = LocalFileSystem._strip_protocol(path)
     assert "file:" not in stripped
     assert stripped.endswith("/foo/bar")
+    if WIN:
+        assert (
+            LocalFileSystem._strip_protocol("file://C:\\path\\file") == "C:/path/file"
+        )
 
 
 def test_mkdir_twice_faile(tmpdir):

fsspec/mapping.py

@@ -40,7 +40,7 @@ class FSMap(MutableMapping):
 
     def __init__(self, root, fs, check=False, create=False, missing_exceptions=None):
         self.fs = fs
-        self.root = fs._strip_protocol(root).rstrip("/")
+        self.root = fs._strip_protocol(root)
         self._root_key_to_str = fs._strip_protocol(posixpath.join(root, "x"))[:-1]
         if missing_exceptions is None:
             missing_exceptions = (
@@ -142,7 +142,7 @@ def _key_to_str(self, key):
             if isinstance(key, list):
                 key = tuple(key)
             key = str(key)
-        return f"{self._root_key_to_str}{key}"
+        return f"{self._root_key_to_str}{key}".rstrip("/")
 
     def _str_to_key(self, s):
         """Strip path of to leave key name"""

fsspec/tests/test_mapping.py

@@ -200,19 +200,23 @@ def test_fsmap_error_on_protocol_keys():
         _ = m[f"memory://{root}/a"]
 
 
-# on Windows opening a directory will raise PermissionError
-# see: https://bugs.python.org/issue43095
-@pytest.mark.skipif(
-    platform.system() == "Windows", reason="raises PermissionError on windows"
-)
 def test_fsmap_access_with_suffix(tmp_path):
     tmp_path.joinpath("b").mkdir()
     tmp_path.joinpath("b", "a").write_bytes(b"data")
-    m = fsspec.get_mapper(f"file://{tmp_path}")
-
+    if platform.system() == "Windows":
+        # on Windows opening a directory will raise PermissionError
+        # see: https://bugs.python.org/issue43095
+        missing_exceptions = (
+            FileNotFoundError,
+            IsADirectoryError,
+            NotADirectoryError,
+            PermissionError,
+        )
+    else:
+        missing_exceptions = None
+    m = fsspec.get_mapper(f"file://{tmp_path}", missing_exceptions=missing_exceptions)
     with pytest.raises(KeyError):
         _ = m["b/"]
-
     assert m["b/a/"] == b"data"