Use robust shebang code for all shebang modification

news/13389.bugfix.rst

@@ -0,0 +1 @@
+Rewriting of ``#!python`` headers in scripts has been improved to handle unusual paths more robustly.

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

@@ -90,14 +90,16 @@ def fix_script(path: str) -> bool:
     assert os.path.isfile(path)
 
     with open(path, "rb") as script:
-        firstline = script.readline()
-        if not firstline.startswith(b"#!python"):
+        prelude = script.readline()
+        if (m := re.match(rb"^#!(python[^\s]*)(\s.*)?$", prelude)) is None:
             return False
-        exename = sys.executable.encode(sys.getfilesystemencoding())
-        firstline = b"#!" + exename + os.linesep.encode("ascii")
+        exe, post_interp = m.groups()
+        options = {"gui": exe.startswith(b"pythonw")}
+        sm = ScriptMaker(None, None)
+        prelude = sm._get_shebang("utf-8", post_interp or b"", options)
         rest = script.read()
     with open(path, "wb") as script:
-        script.write(firstline)
+        script.write(prelude)
         script.write(rest)
     return True
 

tests/functional/test_install_wheel.py

@@ -1,17 +1,26 @@
+from __future__ import annotations
+
 import base64
 import csv
 import hashlib
 import os
 import shutil
 import sysconfig
 from pathlib import Path
-from typing import Any
+from typing import TYPE_CHECKING, Any
 
 import pytest
 
-from tests.lib import PipTestEnvironment, TestData, create_basic_wheel_for_package
+from tests.lib import create_basic_wheel_for_package
 from tests.lib.wheel import WheelBuilder, make_wheel
 
+from ..lib.venv import VirtualEnvironment
+
+if TYPE_CHECKING:
+    from collections.abc import Callable
+
+    from tests.lib import PipTestEnvironment, ScriptFactory, TestData
+
 
 # assert_installed expects a package subdirectory, so give it to them
 def make_wheel_with_file(name: str, version: str, **kwargs: Any) -> WheelBuilder:
@@ -366,18 +375,29 @@ def test_wheel_record_lines_have_hash_for_data_files(
     ]
 
 
+@pytest.mark.parametrize(
+    "ws_dirname", ["work space", "workspace"], ids=["spaces", "no_spaces"]
+)
+@pytest.mark.parametrize("executable", ["python", "pythonw"])
 def test_wheel_record_lines_have_updated_hash_for_scripts(
-    script: PipTestEnvironment,
+    tmpdir: Path,
+    virtualenv_factory: Callable[[Path], VirtualEnvironment],
+    script_factory: ScriptFactory,
+    ws_dirname: str,
+    executable: str,
 ) -> None:
     """
     pip rewrites "#!python" shebang lines in scripts when it installs them;
     make sure it updates the RECORD file correspondingly.
     """
+    (tmpdir / ws_dirname).mkdir(exist_ok=True, parents=True)
+    virtualenv = virtualenv_factory(tmpdir / ws_dirname / "venv")
+    script = script_factory(tmpdir / ws_dirname, virtualenv)
     package = make_wheel(
         "simple",
         "0.1.0",
         extra_data_files={
-            "scripts/dostuff": "#!python\n",
+            "scripts/dostuff": f"#!{executable}\n",
         },
     ).save_to_dir(script.scratch_path)
     script.pip("install", package)
@@ -388,7 +408,10 @@ def test_wheel_record_lines_have_updated_hash_for_scripts(
 
     script_path = script.bin_path / "dostuff"
     script_contents = script_path.read_bytes()
-    assert not script_contents.startswith(b"#!python\n")
+    expected_prefix = (
+        b"#!/bin/sh\n'''exec' \"" if " " in ws_dirname else b"#!"
+    ) + f"{script.bin_path}{os.path.sep}{executable}".encode()
+    assert script_contents.startswith(expected_prefix)
 
     script_digest = hashlib.sha256(script_contents).digest()
     script_digest_b64 = (