Replace captured_output() and get_url_scheme() with stdlib alternatives

news/c678d9e3-4844-4298-a46c-80768b38f652.trivial.rst

@@ -0,0 +1 @@
+Replace ``captured_output()`` and ``get_url_scheme()`` with stdlib alternatives.

src/pip/_internal/req/req_file.py

@@ -26,7 +26,6 @@
 from pip._internal.exceptions import InstallationError, RequirementsFileParseError
 from pip._internal.models.search_scope import SearchScope
 from pip._internal.utils.encoding import auto_decode
-from pip._internal.utils.urls import get_url_scheme
 
 if TYPE_CHECKING:
     from pip._internal.index.package_finder import PackageFinder
@@ -533,8 +532,7 @@ def get_file_content(url: str, session: "PipSession") -> Tuple[str, str]:
     :param url:         File path or url.
     :param session:     PipSession instance.
     """
-    scheme = get_url_scheme(url)
-
+    scheme = urllib.parse.urlsplit(url).scheme
     # Pip has special support for file:// URLs (LocalFSAdapter).
     if scheme in ["http", "https", "file"]:
         # Delay importing heavy network modules until absolutely necessary.

src/pip/_internal/utils/misc.py

@@ -1,4 +1,3 @@
-import contextlib
 import errno
 import getpass
 import hashlib
@@ -11,6 +10,7 @@
 import sys
 import sysconfig
 import urllib.parse
+from contextlib import redirect_stderr, redirect_stdout
 from dataclasses import dataclass
 from functools import partial
 from io import StringIO
@@ -400,38 +400,21 @@ def encoding(self) -> str:  # type: ignore
         return self.orig_stream.encoding
 
 
-@contextlib.contextmanager
-def captured_output(stream_name: str) -> Generator[StreamWrapper, None, None]:
-    """Return a context manager used by captured_stdout/stdin/stderr
-    that temporarily replaces the sys stream *stream_name* with a StringIO.
-
-    Taken from Lib/support/__init__.py in the CPython repo.
-    """
-    orig_stdout = getattr(sys, stream_name)
-    setattr(sys, stream_name, StreamWrapper.from_stream(orig_stdout))
-    try:
-        yield getattr(sys, stream_name)
-    finally:
-        setattr(sys, stream_name, orig_stdout)
-
-
 def captured_stdout() -> ContextManager[StreamWrapper]:
     """Capture the output of sys.stdout:
 
-       with captured_stdout() as stdout:
-           print('hello')
-       self.assertEqual(stdout.getvalue(), 'hello\n')
-
-    Taken from Lib/support/__init__.py in the CPython repo.
+    with captured_stdout() as stdout:
+        print('hello')
+    self.assertEqual(stdout.getvalue(), 'hello\n')
     """
-    return captured_output("stdout")
+    return redirect_stdout(StreamWrapper.from_stream(sys.stdout))
 
 
 def captured_stderr() -> ContextManager[StreamWrapper]:
     """
     See captured_stdout().
     """
-    return captured_output("stderr")
+    return redirect_stderr(StreamWrapper.from_stream(sys.stderr))
 
 
 # Simulates an enum

src/pip/_internal/utils/urls.py

@@ -2,17 +2,10 @@
 import string
 import urllib.parse
 import urllib.request
-from typing import Optional
 
 from .compat import WINDOWS
 
 
-def get_url_scheme(url: str) -> Optional[str]:
-    if ":" not in url:
-        return None
-    return url.split(":", 1)[0].lower()
-
-
 def path_to_url(path: str) -> str:
     """
     Convert a path to a file: URL.  The path will be made absolute and have

src/pip/_internal/vcs/versioncontrol.py

@@ -38,7 +38,6 @@
     format_command_args,
     make_command,
 )
-from pip._internal.utils.urls import get_url_scheme
 
 __all__ = ["vcs"]
 
@@ -52,8 +51,8 @@ def is_url(name: str) -> bool:
     """
     Return true if the name looks like a URL.
     """
-    scheme = get_url_scheme(name)
-    if scheme is None:
+    scheme = urllib.parse.urlsplit(name).scheme
+    if not scheme:
         return False
     return scheme in ["http", "https", "file", "ftp"] + vcs.all_schemes
 

tests/unit/test_urls.py

@@ -1,24 +1,10 @@
 import os
 import sys
 import urllib.request
-from typing import Optional
 
 import pytest
 
-from pip._internal.utils.urls import get_url_scheme, path_to_url, url_to_path
-
-
-@pytest.mark.parametrize(
-    "url,expected",
-    [
-        ("http://localhost:8080/", "http"),
-        ("file:c:/path/to/file", "file"),
-        ("file:/dev/null", "file"),
-        ("", None),
-    ],
-)
-def test_get_url_scheme(url: str, expected: Optional[str]) -> None:
-    assert get_url_scheme(url) == expected
+from pip._internal.utils.urls import path_to_url, url_to_path
 
 
 @pytest.mark.skipif("sys.platform == 'win32'")