pre-commit/pre_commit/languages/ruby.py

from __future__ import annotations

import contextlib
import functools
import importlib.resources
import os
import os.path
import shutil
import tarfile
from collections.abc import Generator
from collections.abc import Sequence
from typing import IO

import pre_commit.constants as C
from pre_commit import lang_base
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.prefix import Prefix
from pre_commit.util import CalledProcessError

ENVIRONMENT_DIR = 'rbenv'
health_check = lang_base.basic_health_check
run_hook = lang_base.basic_run_hook


def _resource_bytesio(filename: str) -> IO[bytes]:
    files = importlib.resources.files('pre_commit.resources')
    return files.joinpath(filename).open('rb')


@functools.lru_cache(maxsize=1)
def get_default_version() -> str:
    if all(lang_base.exe_exists(exe) for exe in ('ruby', 'gem')):
        return 'system'
    else:
        return C.DEFAULT


def get_env_patch(
        venv: str,
        language_version: str,
) -> PatchesT:
    patches: PatchesT = (
        ('GEM_HOME', os.path.join(venv, 'gems')),
        ('GEM_PATH', UNSET),
        ('BUNDLE_IGNORE_CONFIG', '1'),
        ('BUNDLE_GEMFILE', os.path.join(venv, 'Gemfile'))
    )
    if language_version == 'system':
        patches += (
            (
                'PATH', (
                    os.path.join(venv, 'gems', 'bin'), os.pathsep,
                    Var('PATH'),
                ),
            ),
        )
    else:  # pragma: win32 no cover
        patches += (
            ('RBENV_ROOT', venv),
            (
                'PATH', (
                    os.path.join(venv, 'gems', 'bin'), os.pathsep,
                    os.path.join(venv, 'shims'), os.pathsep,
                    os.path.join(venv, 'bin'), os.pathsep, Var('PATH'),
                ),
            ),
        )
    if language_version not in {'system', 'default'}:  # pragma: win32 no cover
        patches += (('RBENV_VERSION', language_version),)

    return patches


@contextlib.contextmanager
def in_env(prefix: Prefix, version: str) -> Generator[None, None, None]:
    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)
    with envcontext(get_env_patch(envdir, version)):
        yield


def _extract_resource(filename: str, dest: str) -> None:
    with _resource_bytesio(filename) as bio:
        with tarfile.open(fileobj=bio) as tf:
            tf.extractall(dest)


def _install_rbenv(
        prefix: Prefix,
        version: str,
) -> None:  # pragma: win32 no cover
    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)

    _extract_resource('rbenv.tar.gz', prefix.path('.'))
    shutil.move(prefix.path('rbenv'), envdir)

    # Only install ruby-build if the version is specified
    if version != C.DEFAULT:
        plugins_dir = os.path.join(envdir, 'plugins')
        _extract_resource('ruby-download.tar.gz', plugins_dir)
        _extract_resource('ruby-build.tar.gz', plugins_dir)


def _install_ruby(
        prefix: Prefix,
        version: str,
) -> None:  # pragma: win32 no cover
    try:
        lang_base.setup_cmd(prefix, ('rbenv', 'download', version))
    except CalledProcessError:  # pragma: no cover (usually find with download)
        # Failed to download from mirror for some reason, build it instead
        lang_base.setup_cmd(prefix, ('rbenv', 'install', version))


def install_environment(
        prefix: Prefix, version: str, additional_dependencies: Sequence[str],
) -> None:
    envdir = lang_base.environment_dir(prefix, ENVIRONMENT_DIR, version)

    if version != 'system':  # pragma: win32 no cover
        _install_rbenv(prefix, version)
        with in_env(prefix, version):
            # Need to call this before installing so rbenv's directories
            # are set up
            lang_base.setup_cmd(prefix, ('rbenv', 'init', '-'))
            if version != C.DEFAULT:
                _install_ruby(prefix, version)
            # Need to call this after installing to set up the shims
            lang_base.setup_cmd(prefix, ('rbenv', 'rehash'))

    with in_env(prefix, version):
        if not os.path.exists(envdir):
            os.makedirs(envdir)
        with open(os.path.join(envdir, 'Gemfile'), 'w') as f:
            # create an empty file here to avoid letting bundler load
            # the calling application's gems
            pass
        lang_base.setup_cmd(
            prefix, ('gem', 'build', *prefix.star('.gemspec')),
        )
        lang_base.setup_cmd(
            prefix,
            (
                'gem', 'install',
                '--no-document', '--no-format-executable',
                '--no-user-install',
                '--install-dir', os.path.join(envdir, 'gems'),
                '--bindir', os.path.join(envdir, 'gems', 'bin'),
                *prefix.star('.gem'), *additional_dependencies,
            ),
        )