import contextlib
import functools
import os
import sys
from typing import Dict
from typing import Generator
from typing import Optional
from typing import Sequence
from typing import Tuple
import pre_commit.constants as C
from pre_commit.envcontext import envcontext
from pre_commit.envcontext import PatchesT
from pre_commit.envcontext import UNSET
from pre_commit.envcontext import Var
from pre_commit.hook import Hook
from pre_commit.languages import helpers
from pre_commit.parse_shebang import find_executable
from pre_commit.prefix import Prefix
from pre_commit.util import CalledProcessError
from pre_commit.util import clean_path_on_failure
from pre_commit.util import cmd_output
from pre_commit.util import cmd_output_b
ENVIRONMENT_DIR = 'py_env'
@functools.lru_cache(maxsize=None)
def _version_info(exe: str) -> str:
prog = 'import sys;print(".".join(str(p) for p in sys.version_info))'
try:
return cmd_output(exe, '-S', '-c', prog)[1].strip()
except CalledProcessError:
return f'<>'
def _read_pyvenv_cfg(filename: str) -> Dict[str, str]:
ret = {}
with open(filename) as f:
for line in f:
try:
k, v = line.split('=')
except ValueError: # blank line / comment / etc.
continue
else:
ret[k.strip()] = v.strip()
return ret
def bin_dir(venv: str) -> str:
"""On windows there's a different directory for the virtualenv"""
bin_part = 'Scripts' if os.name == 'nt' else 'bin'
return os.path.join(venv, bin_part)
def get_env_patch(venv: str) -> PatchesT:
return (
('PIP_DISABLE_PIP_VERSION_CHECK', '1'),
('PYTHONHOME', UNSET),
('VIRTUAL_ENV', venv),
('PATH', (bin_dir(venv), os.pathsep, Var('PATH'))),
)
def _find_by_py_launcher(
version: str,
) -> Optional[str]: # pragma: no cover (windows only)
if version.startswith('python'):
num = version[len('python'):]
cmd = ('py', f'-{num}', '-c', 'import sys; print(sys.executable)')
env = dict(os.environ, PYTHONIOENCODING='UTF-8')
try:
return cmd_output(*cmd, env=env)[1].strip()
except CalledProcessError:
pass
return None
def _find_by_sys_executable() -> Optional[str]:
def _norm(path: str) -> Optional[str]:
_, exe = os.path.split(path.lower())
exe, _, _ = exe.partition('.exe')
if exe not in {'python', 'pythonw'} and find_executable(exe):
return exe
return None
# On linux, I see these common sys.executables:
#
# system `python`: /usr/bin/python -> python2.7
# system `python2`: /usr/bin/python2 -> python2.7
# virtualenv v: v/bin/python (will not return from this loop)
# virtualenv v -ppython2: v/bin/python -> python2
# virtualenv v -ppython2.7: v/bin/python -> python2.7
# virtualenv v -ppypy: v/bin/python -> v/bin/pypy
for path in (sys.executable, os.path.realpath(sys.executable)):
exe = _norm(path)
if exe:
return exe
return None
@functools.lru_cache(maxsize=1)
def get_default_version() -> str: # pragma: no cover (platform dependent)
# First attempt from `sys.executable` (or the realpath)
exe = _find_by_sys_executable()
if exe:
return exe
# Next try the `pythonX.X` executable
exe = f'python{sys.version_info[0]}.{sys.version_info[1]}'
if find_executable(exe):
return exe
if _find_by_py_launcher(exe):
return exe
# We tried!
return C.DEFAULT
def _sys_executable_matches(version: str) -> bool:
if version == 'python':
return True
elif not version.startswith('python'):
return False
try:
info = tuple(int(p) for p in version[len('python'):].split('.'))
except ValueError:
return False
return sys.version_info[:len(info)] == info
def norm_version(version: str) -> str:
if version == C.DEFAULT:
return os.path.realpath(sys.executable)
# first see if our current executable is appropriate
if _sys_executable_matches(version):
return sys.executable
if os.name == 'nt': # pragma: no cover (windows)
version_exec = _find_by_py_launcher(version)
if version_exec:
return version_exec
# Try looking up by name
version_exec = find_executable(version)
if version_exec and version_exec != version:
return version_exec
# Otherwise assume it is a path
return os.path.expanduser(version)
@contextlib.contextmanager
def in_env(
prefix: Prefix,
language_version: str,
) -> Generator[None, None, None]:
directory = helpers.environment_dir(ENVIRONMENT_DIR, language_version)
envdir = prefix.path(directory)
with envcontext(get_env_patch(envdir)):
yield
def healthy(prefix: Prefix, language_version: str) -> bool:
directory = helpers.environment_dir(ENVIRONMENT_DIR, language_version)
envdir = prefix.path(directory)
pyvenv_cfg = os.path.join(envdir, 'pyvenv.cfg')
# created with "old" virtualenv
if not os.path.exists(pyvenv_cfg):
return False
exe_name = 'python.exe' if sys.platform == 'win32' else 'python'
py_exe = prefix.path(bin_dir(envdir), exe_name)
cfg = _read_pyvenv_cfg(pyvenv_cfg)
return (
'version_info' in cfg and
# always use uncached lookup here in case we replaced an unhealthy env
_version_info.__wrapped__(py_exe) == cfg['version_info'] and (
'base-executable' not in cfg or
_version_info(cfg['base-executable']) == cfg['version_info']
)
)
def install_environment(
prefix: Prefix,
version: str,
additional_dependencies: Sequence[str],
) -> None:
envdir = prefix.path(helpers.environment_dir(ENVIRONMENT_DIR, version))
python = norm_version(version)
venv_cmd = (sys.executable, '-mvirtualenv', envdir, '-p', python)
install_cmd = ('python', '-mpip', 'install', '.', *additional_dependencies)
with clean_path_on_failure(envdir):
cmd_output_b(*venv_cmd, cwd='/')
with in_env(prefix, version):
helpers.run_setup_cmd(prefix, install_cmd)
def run_hook(
hook: Hook,
file_args: Sequence[str],
color: bool,
) -> Tuple[int, bytes]:
with in_env(hook.prefix, hook.language_version):
return helpers.run_xargs(hook, hook.cmd, file_args, color=color)