Preserve mtime of files installed from wheels

news/13207.bugfix.rst

@@ -0,0 +1 @@
+Preserve ``mtime`` of files installed from wheels.

src/pip/_internal/operations/install/wheel.py

@@ -8,6 +8,7 @@
 import csv
 import importlib
 import logging
+import os
 import os.path
 import re
 import shutil
@@ -16,6 +17,7 @@
 import warnings
 from base64 import urlsafe_b64encode
 from collections.abc import Generator, Iterable, Iterator, Sequence
+from datetime import datetime
 from email.message import Message
 from itertools import chain, filterfalse, starmap
 from typing import (
@@ -337,6 +339,13 @@ def get_console_script_specs(console: dict[str, str]) -> list[str]:
     return scripts_to_generate
 
 
+def _set_extracted_file_mtime(extracted_file: str, zipinfo: ZipInfo) -> None:
+    # ZipInfo.date_time is interpreted as a local time, so we must account for
+    # the local timezone when computing the target timestamp
+    mtime = datetime(*zipinfo.date_time).astimezone().timestamp()
+    os.utime(extracted_file, (mtime, mtime))
+
+
 class ZipBackedFile:
     def __init__(
         self, src_record_path: RecordPath, dest_path: str, zip_file: ZipFile
@@ -371,6 +380,8 @@ def save(self) -> None:
                     blocksize = min(zipinfo.file_size, 1024 * 1024)
                     shutil.copyfileobj(f, dest, blocksize)
 
+        _set_extracted_file_mtime(self.dest_path, zipinfo)
+
         if zip_item_is_executable(zipinfo):
             set_extracted_file_to_default_mode_plus_executable(self.dest_path)
 

tests/functional/test_install_wheel.py

@@ -4,6 +4,7 @@
 import os
 import shutil
 import sysconfig
+from datetime import datetime
 from pathlib import Path
 from typing import Any
 
@@ -801,3 +802,20 @@ def test_wheel_with_unknown_subdir_in_data_dir_has_reasonable_error(
 
     result = script.pip("install", "--no-index", str(wheel_path), expect_error=True)
     assert "simple-0.1.0.data/unknown/hello.txt" in result.stderr
+
+
+def test_wheel_install_mtime(script: PipTestEnvironment, data: TestData) -> None:
+    """Check that installed file mtime matches value inside the given wheel"""
+    to_install = data.packages.joinpath("simplewheel-1.0-py2.py3-none-any.whl")
+    result = script.pip("install", to_install)
+    result.assert_installed("simplewheel", editable=False)
+
+    pth = script.site_packages / "simplewheel" / "__init__.py"
+    item = result.files_created[pth]
+
+    # These are both naive, so it is reasonable to compare them, and a bit more
+    # legible than comparing to a timestamp expectation
+    dt = datetime.fromtimestamp(item.mtime)
+    expected_dt = datetime(2018, 4, 17, 9, 57, 4)
+
+    assert dt == expected_dt, "Extracted file mtime does not match expected value"