Print message when installing repositories.

pre_commit/languages/all.py

@@ -5,7 +5,10 @@ from pre_commit.languages import ruby
 from pre_commit.languages import script
 from pre_commit.languages import system
 
-# A language implements the following two functions in its module:
+# A language implements the following constant and two functions in its module:
+#
+# # Use None for no environment
+# ENVIRONMENT_DIR = 'foo_env'
 #
 # def install_environment(repo_cmd_runner):
 #     """Installs a repository in the given repository.  Note that the current

pre_commit/languages/node.py

@@ -6,7 +6,7 @@ from pre_commit.prefixed_command_runner import CalledProcessError
 from pre_commit.util import clean_path_on_failure
 
 
-NODE_ENV = 'node_env'
+ENVIRONMENT_DIR = 'node_env'
 
 
 class NodeEnv(python.PythonEnv):
@@ -15,7 +15,7 @@ class NodeEnv(python.PythonEnv):
         base = super(NodeEnv, self).env_prefix
         return ' '.join([
             base,
-            '. {{prefix}}{0}/bin/activate &&'.format(NODE_ENV)]
+            '. {{prefix}}{0}/bin/activate &&'.format(ENVIRONMENT_DIR)]
         )
 
 
@@ -27,30 +27,26 @@ def in_env(repo_cmd_runner):
 def install_environment(repo_cmd_runner):
     assert repo_cmd_runner.exists('package.json')
 
-    # Return immediately if we already have a virtualenv
+    with clean_path_on_failure(repo_cmd_runner.path(python.ENVIRONMENT_DIR)):
-    if repo_cmd_runner.exists(NODE_ENV):
-        return
-
-    with clean_path_on_failure(repo_cmd_runner.path(python.PY_ENV)):
         repo_cmd_runner.run(
-            ['virtualenv', '{{prefix}}{0}'.format(python.PY_ENV)],
+            ['virtualenv', '{{prefix}}{0}'.format(python.ENVIRONMENT_DIR)],
         )
 
         with python.in_env(repo_cmd_runner) as python_env:
             python_env.run('pip install nodeenv')
 
-            with clean_path_on_failure(repo_cmd_runner.path(NODE_ENV)):
+            with clean_path_on_failure(repo_cmd_runner.path(ENVIRONMENT_DIR)):
                 # Try and use the system level node executable first
                 try:
                     python_env.run(
-                        'nodeenv -n system {{prefix}}{0}'.format(NODE_ENV),
+                        'nodeenv -n system {{prefix}}{0}'.format(ENVIRONMENT_DIR),
                     )
                 except CalledProcessError:
                     # TODO: log failure here
                     # cleanup
-                    # TODO: local.path(NODE_ENV).delete()
+                    # TODO: local.path(ENVIRONMENT_DIR).delete()
                     python_env.run(
-                        'nodeenv --jobs 4 {{prefix}}{0}'.format(NODE_ENV),
+                        'nodeenv --jobs 4 {{prefix}}{0}'.format(ENVIRONMENT_DIR),
                     )
 
                 with in_env(repo_cmd_runner) as node_env:

pre_commit/languages/python.py

@@ -5,13 +5,13 @@ from pre_commit.languages import helpers
 from pre_commit.util import clean_path_on_failure
 
 
-PY_ENV = 'py_env'
+ENVIRONMENT_DIR = 'py_env'
 
 
 class PythonEnv(helpers.Environment):
     @property
     def env_prefix(self):
-        return '. {{prefix}}{0}/bin/activate &&'.format(PY_ENV)
+        return '. {{prefix}}{0}/bin/activate &&'.format(ENVIRONMENT_DIR)
 
 
 @contextlib.contextmanager
@@ -21,13 +21,10 @@ def in_env(repo_cmd_runner):
 
 def install_environment(repo_cmd_runner):
     assert repo_cmd_runner.exists('setup.py')
-    # Return immediately if we already have a virtualenv
-    if repo_cmd_runner.exists(PY_ENV):
-        return
 
     # Install a virtualenv
-    with clean_path_on_failure(repo_cmd_runner.path(PY_ENV)):
+    with clean_path_on_failure(repo_cmd_runner.path(ENVIRONMENT_DIR)):
-        repo_cmd_runner.run(['virtualenv', '{{prefix}}{0}'.format(PY_ENV)])
+        repo_cmd_runner.run(['virtualenv', '{{prefix}}{0}'.format(ENVIRONMENT_DIR)])
         with in_env(repo_cmd_runner) as env:
             env.run('cd {prefix} && pip install .')
 

pre_commit/languages/ruby.py

@@ -5,13 +5,13 @@ from pre_commit.languages import helpers
 from pre_commit.util import clean_path_on_failure
 
 
-RVM_ENV = 'rvm_env'
+ENVIRONMENT_DIR = 'rvm_env'
 
 
 class RubyEnv(helpers.Environment):
     @property
     def env_prefix(self):
-        return '. {{prefix}}{0}/bin/activate &&'.format(RVM_ENV)
+        return '. {{prefix}}{0}/bin/activate &&'.format(ENVIRONMENT_DIR)
 
 
 @contextlib.contextmanager
@@ -21,11 +21,11 @@ def in_env(repo_cmd_runner):
 
 def install_environment(repo_cmd_runner):
     # Return immediately if we already have a virtualenv
-    if repo_cmd_runner.exists(RVM_ENV):
+    if repo_cmd_runner.exists(ENVIRONMENT_DIR):
         return
 
-    with clean_path_on_failure(repo_cmd_runner.path(RVM_ENV)):
+    with clean_path_on_failure(repo_cmd_runner.path(ENVIRONMENT_DIR)):
-        repo_cmd_runner.run(['__rvm-env.sh', '{{prefix}}{0}'.format(RVM_ENV)])
+        repo_cmd_runner.run(['__rvm-env.sh', '{{prefix}}{0}'.format(ENVIRONMENT_DIR)])
         with in_env(repo_cmd_runner) as env:
             env.run('cd {prefix} && bundle install')
 

pre_commit/languages/script.py

@@ -1,7 +1,9 @@
 
+ENVIRONMENT_DIR = None
+
+
 def install_environment(repo_cmd_runner):
     """Installation for script type is a noop."""
-    pass
 
 
 def run_hook(repo_cmd_runner, hook, file_args):

pre_commit/languages/system.py

@@ -1,7 +1,9 @@
 
+ENVIRONMENT_DIR = None
+
+
 def install_environment(repo_cmd_runner):
     """Installation for system type is a noop."""
-    pass
 
 
 def run_hook(repo_cmd_runner, hook, file_args):

pre_commit/repository.py

@@ -1,4 +1,6 @@
 
+from __future__ import print_function
+
 import contextlib
 from plumbum import local
 
@@ -63,6 +65,10 @@ class Repository(object):
                 # Project already exists, no reason to re-create it
                 return
 
+            # Checking out environment for the first time
+            print('Installing environment for {0}.'.format(self.repo_url))
+            print('Once installed this environment will be reused.')
+            print('This may take a few minutes...')
             with clean_path_on_failure(unicode(local.path(self.sha))):
                 local['git']['clone', '--no-checkout', self.repo_url, self.sha]()
                 with self.in_checkout():
@@ -73,6 +79,7 @@ class Repository(object):
             return
 
         self.install(cmd_runner)
+        self.__installed = True
 
     def install(self, cmd_runner):
         """Install the hook repository.
@@ -82,8 +89,15 @@ class Repository(object):
         """
         self.require_created()
         repo_cmd_runner = self.get_cmd_runner(cmd_runner)
-        for language in self.languages:
+        for language_name in self.languages:
-            languages[language].install_environment(repo_cmd_runner)
+            language = languages[language_name]
+            if (
+                language.ENVIRONMENT_DIR is None or
+                repo_cmd_runner.exists(language.ENVIRONMENT_DIR)
+            ):
+                # The language is already installed
+                continue
+            language.install_environment(repo_cmd_runner)
 
     @contextlib.contextmanager
     def in_checkout(self):

tests/languages/all_test.py

@@ -9,3 +9,4 @@ from pre_commit.languages.all import languages
 def test_all_languages_support_interface(language):
     assert hasattr(languages[language], 'install_environment')
     assert hasattr(languages[language], 'run_hook')
+    assert hasattr(languages[language], 'ENVIRONMENT_DIR')

tests/repository_test.py

@@ -1,3 +1,5 @@
+import __builtin__
+import mock
 import os
 import pytest
 
@@ -130,3 +132,35 @@ def test_sha(mock_repo_config):
 def test_languages(config_for_python_hooks_repo):
     repo = Repository(config_for_python_hooks_repo)
     assert repo.languages == set(['python'])
+
+
+@pytest.yield_fixture
+def print_mock():
+    with mock.patch.object(__builtin__, 'print', autospec=True) as print_mock:
+        yield print_mock
+
+
+def test_prints_while_creating(config_for_python_hooks_repo, print_mock):
+    repo = Repository(config_for_python_hooks_repo)
+    repo.require_created()
+    print_mock.assert_called_with('This may take a few minutes...')
+    print_mock.reset_mock()
+    # Reinstall with same repo should not trigger another install
+    repo.require_created()
+    assert print_mock.call_count == 0
+    # Reinstall on another run should not trigger another install
+    repo = Repository(config_for_python_hooks_repo)
+    repo.require_created()
+    assert print_mock.call_count == 0
+
+
+def test_reinstall(config_for_python_hooks_repo):
+    repo = Repository(config_for_python_hooks_repo)
+    repo.require_installed(PrefixedCommandRunner(C.HOOKS_WORKSPACE))
+    # Reinstall with same repo should not trigger another install
+    # TODO: how to assert this?
+    repo.require_installed(PrefixedCommandRunner(C.HOOKS_WORKSPACE))
+    # Reinstall on another run should not trigger another install
+    # TODO: how to assert this?
+    repo = Repository(config_for_python_hooks_repo)
+    repo.require_installed(PrefixedCommandRunner(C.HOOKS_WORKSPACE))