From 35faee2f30d2050c4b14172073c3252d150896b8 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Lum=C3=ADr=20Balhar?= <lbalhar@redhat.com>
Date: Thu, 18 Jun 2026 12:00:18 +0000
Subject: [PATCH 1/2] fix: replace deprecated posixpath.commonprefix() with
 startswith()

os.path.commonprefix() is deprecated in Python 3.15 and emits a
DeprecationWarning. Replace all three usages with str.startswith()
checks, which are also semantically more correct (commonprefix does
character-level matching and can produce false positives for paths
sharing a string prefix but not a directory boundary).
---
 src/installer/_core.py   | 2 +-
 src/installer/sources.py | 6 ++----
 2 files changed, 3 insertions(+), 5 deletions(-)

diff --git a/src/installer/_core.py b/src/installer/_core.py
index e23f06e..24ed294 100644
--- a/src/installer/_core.py
+++ b/src/installer/_core.py
@@ -42,7 +42,7 @@ def _determine_scheme(
     data_dir = source.data_dir
 
     # If it's in not `{distribution}-{version}.data`, then it's in root_scheme.
-    if posixpath.commonprefix([data_dir, path]) != data_dir:
+    if not path.startswith(data_dir + "/"):
         return root_scheme, path
 
     # Figure out which scheme this goes to.
diff --git a/src/installer/sources.py b/src/installer/sources.py
index 839934f..f76177b 100644
--- a/src/installer/sources.py
+++ b/src/installer/sources.py
@@ -220,7 +220,7 @@ def dist_info_filenames(self) -> list[str]:
             name[len(base) + 1 :]
             for name in self._zipfile.namelist()
             if name[-1:] != "/"
-            if base == posixpath.commonprefix([name, base])
+            if name.startswith(base + "/")
         ]
 
     def read_dist_info(self, filename: str) -> str:
@@ -259,9 +259,7 @@ def validate_record(self, *, validate_contents: bool = True) -> None:
 
             record_args = record_mapping.pop(item.filename, None)
 
-            if self.dist_info_dir == posixpath.commonprefix(
-                [self.dist_info_dir, item.filename]
-            ) and item.filename.split("/")[-1] in ("RECORD.p7s", "RECORD.jws"):
+            if item.filename.startswith(self.dist_info_dir + "/") and item.filename.split("/")[-1] in ("RECORD.p7s", "RECORD.jws"):
                 # both are for digital signatures, and not mentioned in RECORD
                 if record_args is not None:
                     # Incorrectly contained

From 7671087481739236ff40788b9045c4b8a62f98fa Mon Sep 17 00:00:00 2001
From: "pre-commit-ci[bot]"
 <66853113+pre-commit-ci[bot]@users.noreply.github.com>
Date: Thu, 18 Jun 2026 19:03:32 +0000
Subject: [PATCH 2/2] [pre-commit.ci] auto fixes from pre-commit.com hooks

for more information, see https://pre-commit.ci
---
 src/installer/sources.py | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/installer/sources.py b/src/installer/sources.py
index f76177b..cd6291a 100644
--- a/src/installer/sources.py
+++ b/src/installer/sources.py
@@ -259,7 +259,9 @@ def validate_record(self, *, validate_contents: bool = True) -> None:
 
             record_args = record_mapping.pop(item.filename, None)
 
-            if item.filename.startswith(self.dist_info_dir + "/") and item.filename.split("/")[-1] in ("RECORD.p7s", "RECORD.jws"):
+            if item.filename.startswith(
+                self.dist_info_dir + "/"
+            ) and item.filename.split("/")[-1] in ("RECORD.p7s", "RECORD.jws"):
                 # both are for digital signatures, and not mentioned in RECORD
                 if record_args is not None:
                     # Incorrectly contained