From: Hai Shi <shihai1992@gmail.com>
Date: Tue, 13 Aug 2019 19:54:02 +0000 (-0500)
Subject: bpo-37689: add Path.is_relative_to() method (GH-14982)
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=82642a052dc46b2180679518bc8d87e1a28a88b5;p=python
bpo-37689: add Path.is_relative_to() method (GH-14982)
---
diff --git a/Doc/library/pathlib.rst b/Doc/library/pathlib.rst
index 166de8de1f..33fac5f697 100644
--- a/Doc/library/pathlib.rst
+++ b/Doc/library/pathlib.rst
@@ -273,7 +273,7 @@ Methods and properties
.. testsetup::
- from pathlib import PurePosixPath, PureWindowsPath
+ from pathlib import PurePath, PurePosixPath, PureWindowsPath
Pure paths provide the following methods and properties:
@@ -462,6 +462,19 @@ Pure paths provide the following methods and properties:
True
+.. method:: PurePath.is_relative_to(*other)
+
+ Return whether or not this path is relative to the *other* path.
+
+ >>> p = PurePath('/etc/passwd')
+ >>> p.is_relative_to('/etc')
+ True
+ >>> p.is_relative_to('/usr')
+ False
+
+ .. versionadded:: 3.9
+
+
.. method:: PurePath.is_reserved()
With :class:`PureWindowsPath`, return ``True`` if the path is considered
diff --git a/Lib/pathlib.py b/Lib/pathlib.py
index 6355ae8641..80923c7682 100644
--- a/Lib/pathlib.py
+++ b/Lib/pathlib.py
@@ -886,6 +886,15 @@ class PurePath(object):
return self._from_parsed_parts('', root if n == 1 else '',
abs_parts[n:])
+ def is_relative_to(self, *other):
+ """Return True if the path is relative to another path or False.
+ """
+ try:
+ self.relative_to(*other)
+ return True
+ except ValueError:
+ return False
+
@property
def parts(self):
"""An object providing sequence-like access to the
diff --git a/Lib/test/test_pathlib.py b/Lib/test/test_pathlib.py
index f74524d992..cfda0a2188 100644
--- a/Lib/test/test_pathlib.py
+++ b/Lib/test/test_pathlib.py
@@ -619,6 +619,40 @@ class _BasePurePathTest(object):
self.assertRaises(ValueError, p.relative_to, '')
self.assertRaises(ValueError, p.relative_to, P('a'))
+ def test_is_relative_to_common(self):
+ P = self.cls
+ p = P('a/b')
+ self.assertRaises(TypeError, p.is_relative_to)
+ self.assertRaises(TypeError, p.is_relative_to, b'a')
+ self.assertTrue(p.is_relative_to(P()))
+ self.assertTrue(p.is_relative_to(''))
+ self.assertTrue(p.is_relative_to(P('a')))
+ self.assertTrue(p.is_relative_to('a/'))
+ self.assertTrue(p.is_relative_to(P('a/b')))
+ self.assertTrue(p.is_relative_to('a/b'))
+ # With several args.
+ self.assertTrue(p.is_relative_to('a', 'b'))
+ # Unrelated paths.
+ self.assertFalse(p.is_relative_to(P('c')))
+ self.assertFalse(p.is_relative_to(P('a/b/c')))
+ self.assertFalse(p.is_relative_to(P('a/c')))
+ self.assertFalse(p.is_relative_to(P('/a')))
+ p = P('/a/b')
+ self.assertTrue(p.is_relative_to(P('/')))
+ self.assertTrue(p.is_relative_to('/'))
+ self.assertTrue(p.is_relative_to(P('/a')))
+ self.assertTrue(p.is_relative_to('/a'))
+ self.assertTrue(p.is_relative_to('/a/'))
+ self.assertTrue(p.is_relative_to(P('/a/b')))
+ self.assertTrue(p.is_relative_to('/a/b'))
+ # Unrelated paths.
+ self.assertFalse(p.is_relative_to(P('/c')))
+ self.assertFalse(p.is_relative_to(P('/a/b/c')))
+ self.assertFalse(p.is_relative_to(P('/a/c')))
+ self.assertFalse(p.is_relative_to(P()))
+ self.assertFalse(p.is_relative_to(''))
+ self.assertFalse(p.is_relative_to(P('a')))
+
def test_pickling_common(self):
P = self.cls
p = P('/a/b')
@@ -1062,6 +1096,59 @@ class PureWindowsPathTest(_BasePurePathTest, unittest.TestCase):
self.assertRaises(ValueError, p.relative_to, P('//z/Share/Foo'))
self.assertRaises(ValueError, p.relative_to, P('//Server/z/Foo'))
+ def test_is_relative_to(self):
+ P = self.cls
+ p = P('C:Foo/Bar')
+ self.assertTrue(p.is_relative_to(P('c:')))
+ self.assertTrue(p.is_relative_to('c:'))
+ self.assertTrue(p.is_relative_to(P('c:foO')))
+ self.assertTrue(p.is_relative_to('c:foO'))
+ self.assertTrue(p.is_relative_to('c:foO/'))
+ self.assertTrue(p.is_relative_to(P('c:foO/baR')))
+ self.assertTrue(p.is_relative_to('c:foO/baR'))
+ # Unrelated paths.
+ self.assertFalse(p.is_relative_to(P()))
+ self.assertFalse(p.is_relative_to(''))
+ self.assertFalse(p.is_relative_to(P('d:')))
+ self.assertFalse(p.is_relative_to(P('/')))
+ self.assertFalse(p.is_relative_to(P('Foo')))
+ self.assertFalse(p.is_relative_to(P('/Foo')))
+ self.assertFalse(p.is_relative_to(P('C:/Foo')))
+ self.assertFalse(p.is_relative_to(P('C:Foo/Bar/Baz')))
+ self.assertFalse(p.is_relative_to(P('C:Foo/Baz')))
+ p = P('C:/Foo/Bar')
+ self.assertTrue(p.is_relative_to('c:'))
+ self.assertTrue(p.is_relative_to(P('c:/')))
+ self.assertTrue(p.is_relative_to(P('c:/foO')))
+ self.assertTrue(p.is_relative_to('c:/foO/'))
+ self.assertTrue(p.is_relative_to(P('c:/foO/baR')))
+ self.assertTrue(p.is_relative_to('c:/foO/baR'))
+ # Unrelated paths.
+ self.assertFalse(p.is_relative_to(P('C:/Baz')))
+ self.assertFalse(p.is_relative_to(P('C:/Foo/Bar/Baz')))
+ self.assertFalse(p.is_relative_to(P('C:/Foo/Baz')))
+ self.assertFalse(p.is_relative_to(P('C:Foo')))
+ self.assertFalse(p.is_relative_to(P('d:')))
+ self.assertFalse(p.is_relative_to(P('d:/')))
+ self.assertFalse(p.is_relative_to(P('/')))
+ self.assertFalse(p.is_relative_to(P('/Foo')))
+ self.assertFalse(p.is_relative_to(P('//C/Foo')))
+ # UNC paths.
+ p = P('//Server/Share/Foo/Bar')
+ self.assertTrue(p.is_relative_to(P('//sErver/sHare')))
+ self.assertTrue(p.is_relative_to('//sErver/sHare'))
+ self.assertTrue(p.is_relative_to('//sErver/sHare/'))
+ self.assertTrue(p.is_relative_to(P('//sErver/sHare/Foo')))
+ self.assertTrue(p.is_relative_to('//sErver/sHare/Foo'))
+ self.assertTrue(p.is_relative_to('//sErver/sHare/Foo/'))
+ self.assertTrue(p.is_relative_to(P('//sErver/sHare/Foo/Bar')))
+ self.assertTrue(p.is_relative_to('//sErver/sHare/Foo/Bar'))
+ # Unrelated paths.
+ self.assertFalse(p.is_relative_to(P('/Server/Share/Foo')))
+ self.assertFalse(p.is_relative_to(P('c:/Server/Share/Foo')))
+ self.assertFalse(p.is_relative_to(P('//z/Share/Foo')))
+ self.assertFalse(p.is_relative_to(P('//Server/z/Foo')))
+
def test_is_absolute(self):
P = self.cls
# Under NT, only paths with both a drive and a root are absolute.
diff --git a/Misc/NEWS.d/next/Library/2019-07-27-18-00-43.bpo-37689.glEmZi.rst b/Misc/NEWS.d/next/Library/2019-07-27-18-00-43.bpo-37689.glEmZi.rst
new file mode 100644
index 0000000000..2787f9e849
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2019-07-27-18-00-43.bpo-37689.glEmZi.rst
@@ -0,0 +1 @@
+Add :meth:`is_relative_to` in :class:`PurePath` to determine whether or not one path is relative to another.