From 6c1131e8dff2c701414f6d776a0548781367e3cd Mon Sep 17 00:00:00 2001
From: barneygale <barney.gale@gmail.com>
Date: Thu, 13 Apr 2023 19:40:50 +0100
Subject: [PATCH 1/2] GH-103525: Improve exception message from
 `pathlib.PurePath()`

Check that arguments are strings before calling `os.path.join()`.

Also improve performance of `PurePath(PurePath(...))` while we're in the
area: we now use the *unnormalized* string path of such arguments.
---
 Lib/pathlib.py                                | 34 +++++++++++--------
 Lib/test/test_pathlib.py                      |  4 +--
 ...-04-13-19-43-15.gh-issue-103525.uY4VYg.rst |  2 ++
 3 files changed, 24 insertions(+), 16 deletions(-)
 create mode 100644 Misc/NEWS.d/next/Library/2023-04-13-19-43-15.gh-issue-103525.uY4VYg.rst

diff --git a/Lib/pathlib.py b/Lib/pathlib.py
index 4ae1fae6f4b358..599df1953c1377 100644
--- a/Lib/pathlib.py
+++ b/Lib/pathlib.py
@@ -300,18 +300,24 @@ def __reduce__(self):
         return (self.__class__, self.parts)
 
     def __init__(self, *args):
-        if not args:
-            path = ''
-        elif len(args) == 1:
-            path = os.fspath(args[0])
+        paths = []
+        for arg in args:
+            if isinstance(arg, PurePath):
+                path = arg._raw_path
+            else:
+                path = os.fspath(arg)
+                if not isinstance(path, str):
+                    raise TypeError(
+                        "argument should be a str or an os.PathLike "
+                        "object where __fspath__ returns a str, "
+                        f"not {type(path).__name__!r}")
+            paths.append(path)
+        if len(paths) == 0:
+            self._raw_path = ''
+        elif len(paths) == 1:
+            self._raw_path = paths[0]
         else:
-            path = self._flavour.join(*args)
-        if not isinstance(path, str):
-            raise TypeError(
-                "argument should be a str or an os.PathLike "
-                "object where __fspath__ returns a str, "
-                f"not {type(path).__name__!r}")
-        self._raw_path = path
+            self._raw_path = self._flavour.join(*paths)
 
     @classmethod
     def _parse_path(cls, path):
@@ -615,7 +621,7 @@ def joinpath(self, *args):
         paths) or a totally different path (if one of the arguments is
         anchored).
         """
-        return self.__class__(self._raw_path, *args)
+        return self.__class__(self, *args)
 
     def __truediv__(self, key):
         try:
@@ -625,7 +631,7 @@ def __truediv__(self, key):
 
     def __rtruediv__(self, key):
         try:
-            return type(self)(key, self._raw_path)
+            return type(self)(key, self)
         except TypeError:
             return NotImplemented
 
@@ -859,7 +865,7 @@ def absolute(self):
             cwd = self._flavour.abspath(self.drive)
         else:
             cwd = os.getcwd()
-        return type(self)(cwd, self._raw_path)
+        return type(self)(cwd, self)
 
     def resolve(self, strict=False):
         """
diff --git a/Lib/test/test_pathlib.py b/Lib/test/test_pathlib.py
index 3c6da94d094610..85a7438cb27629 100644
--- a/Lib/test/test_pathlib.py
+++ b/Lib/test/test_pathlib.py
@@ -81,9 +81,9 @@ def test_bytes(self):
                    r"where __fspath__ returns a str, not 'bytes'")
         with self.assertRaisesRegex(TypeError, message):
             P(b'a')
-        with self.assertRaises(TypeError):
+        with self.assertRaisesRegex(TypeError, message):
             P(b'a', 'b')
-        with self.assertRaises(TypeError):
+        with self.assertRaisesRegex(TypeError, message):
             P('a', b'b')
         with self.assertRaises(TypeError):
             P('a').joinpath(b'b')
diff --git a/Misc/NEWS.d/next/Library/2023-04-13-19-43-15.gh-issue-103525.uY4VYg.rst b/Misc/NEWS.d/next/Library/2023-04-13-19-43-15.gh-issue-103525.uY4VYg.rst
new file mode 100644
index 00000000000000..1414cb07dd9155
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2023-04-13-19-43-15.gh-issue-103525.uY4VYg.rst
@@ -0,0 +1,2 @@
+Fix misleading exception message when mixed ``str`` and ``bytes`` arguments
+are supplied to :class:`pathlib.PurePath` and :class:`~pathlib.Path`.

From d24465e5af405aee956f7177ea1211ba3c27ca59 Mon Sep 17 00:00:00 2001
From: Barney Gale <barney.gale@gmail.com>
Date: Thu, 13 Apr 2023 20:16:42 +0100
Subject: [PATCH 2/2] Update Lib/pathlib.py

Co-authored-by: Terry Jan Reedy <tjreedy@udel.edu>
---
 Lib/pathlib.py | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/Lib/pathlib.py b/Lib/pathlib.py
index 599df1953c1377..8ef834e68d2d35 100644
--- a/Lib/pathlib.py
+++ b/Lib/pathlib.py
@@ -305,7 +305,10 @@ def __init__(self, *args):
             if isinstance(arg, PurePath):
                 path = arg._raw_path
             else:
-                path = os.fspath(arg)
+                try:
+                    path = os.fspath(arg)
+                except TypeError:
+                    path = arg
                 if not isinstance(path, str):
                     raise TypeError(
                         "argument should be a str or an os.PathLike "