fea: return posixpath for relative_to

upath/_compat.py

@@ -253,34 +253,9 @@ def with_suffix(self, suffix):
                 self.drive, self.root, self._tail[:-1] + [name]
             )
 
-        def relative_to(self, other, /, *_deprecated, walk_up=False):
-            if _deprecated:
-                msg = (
-                    "support for supplying more than one positional argument "
-                    "to pathlib.PurePath.relative_to() is deprecated and "
-                    "scheduled for removal in Python 3.14"
-                )
-                warnings.warn(
-                    f"pathlib.PurePath.relative_to(*args) {msg}",
-                    DeprecationWarning,
-                    stacklevel=2,
-                )
-            other = self.with_segments(other, *_deprecated)
-            for step, path in enumerate([other] + list(other.parents)):  # noqa: B007
-                if self.is_relative_to(path):
-                    break
-                elif not walk_up:
-                    raise ValueError(
-                        f"{str(self)!r} is not in the subpath of {str(other)!r}"
-                    )
-                elif path.name == "..":
-                    raise ValueError(f"'..' segment in {str(other)!r} cannot be walked")
-            else:
-                raise ValueError(
-                    f"{str(self)!r} and {str(other)!r} have different anchors"
-                )
-            parts = [".."] * step + self._tail[len(path._tail) :]
-            return self.with_segments(*parts)
+        # NOTE relative_to was elevated to UPath as otherwise this would
+        # cause a circular dependency
+        # def relative_to(self, other, /, *_deprecated, walk_up=False):
 
         def is_relative_to(self, other, /, *_deprecated):
             if _deprecated:

upath/core.py

@@ -721,7 +721,34 @@ def relative_to(  # type: ignore[override]
                 "paths have different storage_options:"
                 f" {self.storage_options!r} != {other.storage_options!r}"
             )
-        return super().relative_to(other, *_deprecated, walk_up=walk_up)
+
+        if _deprecated:
+            msg = (
+                "support for supplying more than one positional argument "
+                "to pathlib.PurePath.relative_to() is deprecated and "
+                "scheduled for removal in Python 3.14"
+            )
+            warnings.warn(
+                f"pathlib.PurePath.relative_to(*args) {msg}",
+                DeprecationWarning,
+                stacklevel=2,
+            )
+        other = self.with_segments(other, *_deprecated)
+        for step, path in enumerate([other] + list(other.parents)):  # noqa: B007
+            if self.is_relative_to(path):
+                break
+            elif not walk_up:
+                raise ValueError(
+                    f"{str(self)!r} is not in the subpath of {str(other)!r}"
+                )
+            elif path.name == "..":
+                raise ValueError(f"'..' segment in {str(other)!r} cannot be walked")
+        else:
+            raise ValueError(
+                f"{str(self)!r} and {str(other)!r} have different anchors"
+            )
+        parts = [".."] * step + self._tail[len(path._tail) :]
+        return UPath(*parts, **self._storage_options)
 
     def is_relative_to(self, other, /, *_deprecated) -> bool:  # type: ignore[override]
         if isinstance(other, UPath) and self.storage_options != other.storage_options:

upath/implementations/cloud.py

@@ -57,8 +57,7 @@ def iterdir(self):
 
     def relative_to(self, other, /, *_deprecated, walk_up=False):
         # use the parent implementation for the ValueError logic
-        super().relative_to(other, *_deprecated, walk_up=False)
-        return self
+        return super().relative_to(other, *_deprecated, walk_up=walk_up)
 
 
 class GCSPath(CloudPath):

upath/implementations/local.py

@@ -11,6 +11,7 @@
 from typing import Collection
 from typing import MutableMapping
 from urllib.parse import SplitResult
+import warnings
 
 from upath._protocol import compatible_protocol
 from upath.core import UPath

upath/tests/implementations/test_azure.py

@@ -2,6 +2,7 @@
 
 from upath import UPath
 from upath.implementations.cloud import AzurePath
+from upath.implementations.local import PosixUPath
 
 from ..cases import BaseTests
 from ..utils import skip_on_windows
@@ -61,3 +62,21 @@ def test_broken_mkdir(self):
 
         (path / "file").write_text("foo")
         assert path.exists()
+
+    def test_relative_to(self):
+        rel_path = UPath("az:///test_bucket/file.txt").relative_to(UPath("az:///test_bucket"))
+        assert isinstance(rel_path, PosixUPath)
+        assert not rel_path.is_absolute()
+        assert 'file.txt' == rel_path.path 
+
+        walk_path = UPath("az:///test_bucket/file.txt").relative_to(UPath("az:///other_test_bucket"), walk_up=True)
+        assert isinstance(walk_path, PosixUPath)
+        assert not walk_path.is_absolute()
+        assert '../test_bucket/file.txt' == walk_path.path
+
+        with pytest.raises(ValueError):
+            UPath("az:///test_bucket/file.txt").relative_to(UPath("az:///prod_bucket"))
+
+        with pytest.raises(ValueError):
+            UPath("az:///test_bucket/file.txt").relative_to(UPath("file:///test_bucket"))
+

upath/tests/implementations/test_local.py

@@ -1,7 +1,7 @@
 import pytest
 
 from upath import UPath
-from upath.implementations.local import LocalPath
+from upath.implementations.local import LocalPath, PosixUPath
 from upath.tests.cases import BaseTests
 from upath.tests.utils import xfail_if_version
 
@@ -15,6 +15,24 @@ def path(self, local_testdir):
     def test_is_LocalPath(self):
         assert isinstance(self.path, LocalPath)
 
+    def test_relative_to(self):
+        rel_path = UPath("file:///test_bucket/file.txt").relative_to(UPath("file:///test_bucket"))
+        assert isinstance(rel_path, PosixUPath)
+        assert not rel_path.is_absolute()
+        assert 'file.txt' == rel_path.path 
+
+        walk_path = UPath("file:///test_bucket/file.txt").relative_to(UPath("file:///other_test_bucket"), walk_up=True)
+        assert isinstance(walk_path, PosixUPath)
+        assert not walk_path.is_absolute()
+        assert '../test_bucket/file.txt' == walk_path.path
+
+        with pytest.raises(ValueError):
+            UPath("file:///test_bucket/file.txt").relative_to(UPath("file:///prod_bucket"))
+
+        with pytest.raises(ValueError):
+            UPath("file:///test_bucket/file.txt").relative_to(UPath("s3:///test_bucket"))
+
+
 
 @xfail_if_version("fsspec", lt="2023.10.0", reason="requires fsspec>=2023.10.0")
 class TestRayIOFSSpecLocal(BaseTests):

upath/tests/implementations/test_s3.py

@@ -6,7 +6,8 @@
 import fsspec
 import pytest  # noqa: F401
 
-from upath import UPath
+from upath.core import UPath
+from upath.implementations.local import PosixUPath
 from upath.implementations.cloud import S3Path
 
 from ..cases import BaseTests
@@ -53,9 +54,21 @@ def test_rmdir(self):
             self.path.joinpath("file1.txt").rmdir()
 
     def test_relative_to(self):
-        assert "s3://test_bucket/file.txt" == str(
-            UPath("s3://test_bucket/file.txt").relative_to(UPath("s3://test_bucket"))
-        )
+        rel_path = UPath("s3:///test_bucket/file.txt").relative_to(UPath("s3:///test_bucket"))
+        assert isinstance(rel_path, PosixUPath)
+        assert not rel_path.is_absolute()
+        assert 'file.txt' == rel_path.path 
+
+        walk_path = UPath("s3:///test_bucket/file.txt").relative_to(UPath("s3:///other_test_bucket"), walk_up=True)
+        assert isinstance(walk_path, PosixUPath)
+        assert not walk_path.is_absolute()
+        assert '../test_bucket/file.txt' == walk_path.path 
+
+        with pytest.raises(ValueError):
+            UPath("s3:///test_bucket/file.txt").relative_to(UPath("s3:///prod_bucket"))
+
+        with pytest.raises(ValueError):
+            UPath("s3:///test_bucket/file.txt").relative_to(UPath("file:///test_bucket"))
 
     def test_iterdir_root(self):
         client_kwargs = self.path.storage_options["client_kwargs"]