OMG we're running a hook

pre_commit/constants.py

@@ -5,8 +5,8 @@ HOOKS_WORKSPACE = '.pre-commit-files'
 
 MANIFEST_FILE = 'manifest.yaml'
 
-SUPPORTED_LANGUAGES = [
+SUPPORTED_LANGUAGES = set([
     'python',
     'ruby',
     'node',
-]
+])

pre_commit/languages/all.py

@@ -0,0 +1,24 @@
+
+from pre_commit.languages import node
+from pre_commit.languages import python
+from pre_commit.languages import ruby
+
+# A language implements the following two functions in its module:
+#
+# def install_environment():
+#     """Installs a repository in the given repository.  Note that the current
+#     working directory will already be inside the repository.
+#     """
+#
+# def run_hook(hook, file_args):
+#     """Runs a hook and returns the returncode and output of running that hook.
+#
+#     Returns:
+#         (returncode, stdout, stderr)
+#     """
+
+languages = {
+    'node': node,
+    'python': python,
+    'ruby': ruby,
+}

pre_commit/languages/node.py

@@ -0,0 +1,7 @@
+
+def install_environment():
+    raise NotImplementedError
+
+
+def run_hook(hook, file_args):
+    raise NotImplementedError

pre_commit/languages/python.py

@@ -0,0 +1,32 @@
+
+import contextlib
+from plumbum import local
+from plumbum.machines.session import ShellSession
+
+PY_ENV = 'py_env'
+
+
+@contextlib.contextmanager
+def in_env():
+    with ShellSession(local['bash'].popen()) as env:
+        env.run('source {0}/bin/activate'.format(PY_ENV))
+        yield env
+
+
+def install_environment():
+    assert local.path('setup.py').exists()
+    # Install a virtualenv
+    local['virtualenv'][PY_ENV]()
+
+    with in_env() as env:
+        # Run their setup.py
+        env.run('pip install .')
+
+
+def run_hook(hook, file_args):
+    with in_env() as env:
+        # TODO: batch filenames
+        return env.run(
+            ' '.join([hook['entry']] + hook.get('args', []) + list(file_args)),
+            retcode=None,
+        )

pre_commit/languages/ruby.py

@@ -0,0 +1,7 @@
+
+def install_environment():
+    raise NotImplementedError
+
+
+def run_hook(hook, file_args):
+    raise NotImplementedError

pre_commit/repository.py

@@ -5,30 +5,10 @@ from plumbum import local
 import pre_commit.constants as C
 from pre_commit.clientlib.validate_manifest import validate_manifest
 from pre_commit.hooks_workspace import in_hooks_workspace
+from pre_commit.languages.all import languages
 from pre_commit.util import cached_property
 
 
-def install_python(repo):
-    assert local.path('setup.py').exists()
-    local['virtualenv']['py_env']()
-    local['bash']['-c', 'source py_env/bin/activate && pip install .']()
-
-
-def install_ruby(repo):
-    raise NotImplementedError
-
-
-def install_node(repo):
-    raise NotImplementedError
-
-
-language_to_repo_setup_strategy = {
-    'python': install_python,
-    'ruby': install_ruby,
-    'node': install_node,
-}
-
-
 class Repository(object):
     def __init__(self, repo_config):
         self.repo_config = repo_config
@@ -84,4 +64,9 @@ class Repository(object):
         with self.in_checkout():
             for language in C.SUPPORTED_LANGUAGES:
                 if language in self.languages:
-                    language_to_repo_setup_strategy[language](self)
+                    languages[language].install_environment()
+
+    def run_hook(self, hook_id, file_args):
+        with self.in_checkout():
+            hook = self.hooks[hook_id]
+            return languages[hook['language']].run_hook(hook, file_args)

tests/conftest.py

@@ -66,6 +66,7 @@ setup(
         local.path('__init__.py').write('')
         local.path('main.py').write("""
 def func():
+    print 'Hello World'
     return 0
     """)
 

tests/languages/all_test.py

@@ -0,0 +1,15 @@
+
+import pytest
+
+import pre_commit.constants as C
+from pre_commit.languages.all import languages
+
+
+def test_all_languages_have_repo_setups():
+    assert set(languages.keys()) == C.SUPPORTED_LANGUAGES
+
+
+@pytest.mark.parametrize('language', C.SUPPORTED_LANGUAGES)
+def test_all_languages_support_interface(language):
+    assert hasattr(languages[language], 'install_environment')
+    assert hasattr(languages[language], 'run_hook')

tests/repository_test.py

@@ -30,7 +30,6 @@ def test_create_repo_in_env(dummy_repo_config, dummy_git_repo):
 @pytest.mark.integration
 def test_install_python_repo_in_env(python_pre_commit_git_repo, config_for_python_pre_commit_git_repo):
     repo = Repository(config_for_python_pre_commit_git_repo)
-    # TODO: do we need create here?
     repo.install()
 
     assert os.path.exists(
@@ -43,6 +42,16 @@ def test_install_python_repo_in_env(python_pre_commit_git_repo, config_for_pytho
     )
 
 
+@pytest.mark.integration
+def test_run_a_hook_omg(config_for_python_pre_commit_git_repo):
+    repo = Repository(config_for_python_pre_commit_git_repo)
+    repo.install()
+    ret = repo.run_hook('foo', [])
+
+    assert ret[0] == 0
+    assert ret[1] == 'Hello World\n'
+
+
 @pytest.fixture
 def mock_repo_config():
     config = {