1 files changed, 126 insertions, 0 deletions
diff --git a/pre_commit/languages/ruby.py b/pre_commit/languages/ruby.py
new file mode 100644
index 0000000..61241f8
--- /dev/null
+++ b/pre_commit/languages/ruby.py
@@ -0,0 +1,126 @@
+import contextlib
+import os.path
+import shutil
+import tarfile
+from typing import Generator
+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 Var
+from pre_commit.hook import Hook
+from pre_commit.languages import helpers
+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 resource_bytesio
+
+ENVIRONMENT_DIR = 'rbenv'
+get_default_version = helpers.basic_get_default_version
+healthy = helpers.basic_healthy
+
+
+def get_env_patch(
+        venv: str,
+        language_version: str,
+) -> PatchesT:  # pragma: win32 no cover
+    patches: PatchesT = (
+        ('GEM_HOME', os.path.join(venv, 'gems')),
+        ('RBENV_ROOT', venv),
+        ('BUNDLE_IGNORE_CONFIG', '1'),
+        (
+            '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 != C.DEFAULT:
+        patches += (('RBENV_VERSION', language_version),)
+    return patches
+
+
+@contextlib.contextmanager  # pragma: win32 no cover
+def in_env(
+        prefix: Prefix,
+        language_version: str,
+) -> Generator[None, None, None]:
+    envdir = prefix.path(
+        helpers.environment_dir(ENVIRONMENT_DIR, language_version),
+    )
+    with envcontext(get_env_patch(envdir, language_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 = C.DEFAULT,
+) -> None:  # pragma: win32 no cover
+    directory = helpers.environment_dir(ENVIRONMENT_DIR, version)
+
+    _extract_resource('rbenv.tar.gz', prefix.path('.'))
+    shutil.move(prefix.path('rbenv'), prefix.path(directory))
+
+    # Only install ruby-build if the version is specified
+    if version != C.DEFAULT:
+        plugins_dir = prefix.path(directory, '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:
+        helpers.run_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
+        helpers.run_setup_cmd(prefix, ('rbenv', 'install', version))
+
+
+def install_environment(
+        prefix: Prefix, version: str, additional_dependencies: Sequence[str],
+) -> None:  # pragma: win32 no cover
+    additional_dependencies = tuple(additional_dependencies)
+    directory = helpers.environment_dir(ENVIRONMENT_DIR, version)
+    with clean_path_on_failure(prefix.path(directory)):
+        # TODO: this currently will fail if there's no version specified and
+        # there's no system ruby installed.  Is this ok?
+        _install_rbenv(prefix, version=version)
+        with in_env(prefix, version):
+            # Need to call this before installing so rbenv's directories are
+            # set up
+            helpers.run_setup_cmd(prefix, ('rbenv', 'init', '-'))
+            if version != C.DEFAULT:
+                _install_ruby(prefix, version)
+            # Need to call this after installing to set up the shims
+            helpers.run_setup_cmd(prefix, ('rbenv', 'rehash'))
+            helpers.run_setup_cmd(
+                prefix, ('gem', 'build', *prefix.star('.gemspec')),
+            )
+            helpers.run_setup_cmd(
+                prefix,
+                (
+                    'gem', 'install', '--no-document',
+                    *prefix.star('.gem'), *additional_dependencies,
+                ),
+            )
+
+
+def run_hook(
+        hook: Hook,
+        file_args: Sequence[str],
+        color: bool,
+) -> Tuple[int, bytes]:  # pragma: win32 no cover
+    with in_env(hook.prefix, hook.language_version):
+        return helpers.run_xargs(hook, hook.cmd, file_args, color=color)