Pass language_version to the install method for each language.

pre_commit/languages/node.py

@@ -24,7 +24,7 @@ def in_env(repo_cmd_runner):
     yield NodeEnv(repo_cmd_runner)
 
 
-def install_environment(repo_cmd_runner):
+def install_environment(repo_cmd_runner, version='default'):
     assert repo_cmd_runner.exists('package.json')
 
     with clean_path_on_failure(repo_cmd_runner.path(python.ENVIRONMENT_DIR)):

pre_commit/languages/python.py

@@ -18,7 +18,7 @@ def in_env(repo_cmd_runner):
     yield PythonEnv(repo_cmd_runner)
 
 
-def install_environment(repo_cmd_runner):
+def install_environment(repo_cmd_runner, version='default'):
     assert repo_cmd_runner.exists('setup.py')
 
     # Install a virtualenv

pre_commit/languages/ruby.py

@@ -56,7 +56,7 @@ def _install_rbenv(repo_cmd_runner):
         )
 
 
-def install_environment(repo_cmd_runner):
+def install_environment(repo_cmd_runner, version='default'):
     with clean_path_on_failure(repo_cmd_runner.path('rbenv')):
         _install_rbenv(repo_cmd_runner)
         with in_env(repo_cmd_runner) as ruby_env:

pre_commit/languages/script.py

@@ -1,7 +1,7 @@
 ENVIRONMENT_DIR = None
 
 
-def install_environment(repo_cmd_runner):
+def install_environment(repo_cmd_runner, version='default'):
     """Installation for script type is a noop."""
 
 

pre_commit/languages/system.py

@@ -4,7 +4,7 @@ import shlex
 ENVIRONMENT_DIR = None
 
 
-def install_environment(repo_cmd_runner):
+def install_environment(repo_cmd_runner, version='default'):
     """Installation for system type is a noop."""