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"""A single place for constructing and exposing the main parser
"""
import os
import subprocess
import sys
from typing import List, Optional, Tuple
from pip._internal.build_env import get_runnable_pip
from pip._internal.cli import cmdoptions
from pip._internal.cli.parser import ConfigOptionParser, UpdatingDefaultsHelpFormatter
from pip._internal.commands import commands_dict, get_similar_commands
from pip._internal.exceptions import CommandError
from pip._internal.utils.misc import get_pip_version, get_prog
__all__ = ["create_main_parser", "parse_command"]
def create_main_parser() -> ConfigOptionParser:
"""Creates and returns the main parser for pip's CLI"""
parser = ConfigOptionParser(
usage="\n%prog <command> [options]",
add_help_option=False,
formatter=UpdatingDefaultsHelpFormatter(),
name="global",
prog=get_prog(),
)
parser.disable_interspersed_args()
parser.version = get_pip_version()
# add the general options
gen_opts = cmdoptions.make_option_group(cmdoptions.general_group, parser)
parser.add_option_group(gen_opts)
# so the help formatter knows
parser.main = True # type: ignore
# create command listing for description
description = [""] + [
f"{name:27} {command_info.summary}"
for name, command_info in commands_dict.items()
]
parser.description = "\n".join(description)
return parser
def identify_python_interpreter(python: str) -> Optional[str]:
# If the named file exists, use it.
# If it's a directory, assume it's a virtual environment and
# look for the environment's Python executable.
if os.path.exists(python):
if os.path.isdir(python):
# bin/python for Unix, Scripts/python.exe for Windows
# Try both in case of odd cases like cygwin.
for exe in ("bin/python", "Scripts/python.exe"):
py = os.path.join(python, exe)
if os.path.exists(py):
return py
else:
return python
# Could not find the interpreter specified
return None
def parse_command(args: List[str]) -> Tuple[str, List[str]]:
parser = create_main_parser()
# Note: parser calls disable_interspersed_args(), so the result of this
# call is to split the initial args into the general options before the
# subcommand and everything else.
# For example:
# args: ['--timeout=5', 'install', '--user', 'INITools']
# general_options: ['--timeout==5']
# args_else: ['install', '--user', 'INITools']
general_options, args_else = parser.parse_args(args)
# --python
if general_options.python and "_PIP_RUNNING_IN_SUBPROCESS" not in os.environ:
# Re-invoke pip using the specified Python interpreter
interpreter = identify_python_interpreter(general_options.python)
if interpreter is None:
raise CommandError(
f"Could not locate Python interpreter {general_options.python}"
)
pip_cmd = [
interpreter,
get_runnable_pip(),
]
pip_cmd.extend(args)
# Set a flag so the child doesn't re-invoke itself, causing
# an infinite loop.
os.environ["_PIP_RUNNING_IN_SUBPROCESS"] = "1"
returncode = 0
try:
proc = subprocess.run(pip_cmd)
returncode = proc.returncode
except (subprocess.SubprocessError, OSError) as exc:
raise CommandError(f"Failed to run pip under {interpreter}: {exc}")
sys.exit(returncode)
# --version
if general_options.version:
sys.stdout.write(parser.version)
sys.stdout.write(os.linesep)
sys.exit()
# pip || pip help -> print_help()
if not args_else or (args_else[0] == "help" and len(args_else) == 1):
parser.print_help()
sys.exit()
# the subcommand name
cmd_name = args_else[0]
if cmd_name not in commands_dict:
guess = get_similar_commands(cmd_name)
msg = [f'unknown command "{cmd_name}"']
if guess:
msg.append(f'maybe you meant "{guess}"')
raise CommandError(" - ".join(msg))
# all the args without the subcommand
cmd_args = args[:]
cmd_args.remove(cmd_name)
return cmd_name, cmd_args
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