Factor out bash and activate files

pre_commit/languages/helpers.py

@@ -1,6 +1,10 @@
 from __future__ import unicode_literals
 
-import pipes
+from pre_commit.util import cmd_output
+
+
+def run_setup_cmd(runner, cmd):
+    cmd_output(*cmd, cwd=runner.prefix_dir, encoding=None)
 
 
 def environment_dir(ENVIRONMENT_DIR, language_version):
@@ -14,39 +18,12 @@ def file_args_to_stdin(file_args):
     return '\0'.join(list(file_args) + [''])
 
 
-def run_hook(env, hook, file_args):
-    quoted_args = [pipes.quote(arg) for arg in hook['args']]
-    return env.run(
+def run_hook(cmd_args, file_args):
+    return cmd_output(
         # Use -s 4000 (slightly less than posix mandated minimum)
         # This is to prevent "xargs: ... Bad file number" on windows
-        ' '.join(['xargs', '-0', '-s4000', hook['entry']] + quoted_args),
+        'xargs', '-0', '-s4000', *cmd_args,
         stdin=file_args_to_stdin(file_args),
         retcode=None,
-        encoding=None,
+        encoding=None
     )
-
-
-class Environment(object):
-    def __init__(self, repo_cmd_runner, language_version):
-        self.repo_cmd_runner = repo_cmd_runner
-        self.language_version = language_version
-
-    @property
-    def env_prefix(self):
-        """env_prefix is a value that is prefixed to the command that is run.
-
-        Usually this is to source a virtualenv, etc.
-
-        Commands basically end up looking like:
-
-        bash -c '{env_prefix} {cmd}'
-
-        so you'll often want to end your prefix with &&
-        """
-        raise NotImplementedError
-
-    def run(self, cmd, **kwargs):
-        """Returns (returncode, stdout, stderr)."""
-        return self.repo_cmd_runner.run(
-            ['bash', '-c', ' '.join([self.env_prefix, cmd])], **kwargs
-        )