Use virtualenv python from install-time for less virtualenv requirements at commit time.

pre_commit/commands/install_uninstall.py

@@ -6,6 +6,7 @@ import logging
 import os
 import os.path
 import stat
+import sys
 
 from pre_commit.logging_handler import LoggingHandler
 from pre_commit.util import resource_filename
@@ -15,12 +16,13 @@ logger = logging.getLogger('pre_commit')
 
 
 # This is used to identify the hook file we install
-PREVIOUS_IDENTIFYING_HASHES = [
+PREVIOUS_IDENTIFYING_HASHES = (
+    '4d9958c90bc262f47553e2c073f14cfe',
     'd8ee923c46731b42cd95cc869add4062',
-]
+)
 
 
-IDENTIFYING_HASH = '4d9958c90bc262f47553e2c073f14cfe'
+IDENTIFYING_HASH = '49fd668cb42069aa1b6048464be5d395'
 
 
 def is_our_pre_commit(filename):
@@ -63,8 +65,11 @@ def install(runner, overwrite=False, hooks=False):
             )
         )
 
-    with open(runner.pre_commit_path, 'w') as pre_commit_file_obj:
+    with io.open(runner.pre_commit_path, 'w') as pre_commit_file_obj:
-        pre_commit_file_obj.write(open(pre_commit_file).read())
+        contents = io.open(pre_commit_file).read().format(
+            sys_executable=sys.executable,
+        )
+        pre_commit_file_obj.write(contents)
     make_executable(runner.pre_commit_path)
 
     print('pre-commit installed at {0}'.format(runner.pre_commit_path))

pre_commit/output.py

@@ -1,5 +1,6 @@
 from __future__ import unicode_literals
 
+import os
 import subprocess
 import sys
 
@@ -10,7 +11,7 @@ from pre_commit import five
 # TODO: smell: import side-effects
 COLS = int(
     subprocess.Popen(
-        ['tput', 'cols'], stdout=subprocess.PIPE
+        ['tput', 'cols'], stdout=subprocess.PIPE, stderr=open(os.devnull, 'w'),
     ).communicate()[0] or
     # Default in the case of no terminal
     80

pre_commit/resources/pre-commit-hook

@@ -1,6 +1,6 @@
 #!/usr/bin/env bash
 # This is a randomish md5 to identify this script
-# 4d9958c90bc262f47553e2c073f14cfe
+# 49fd668cb42069aa1b6048464be5d395
 
 pushd `dirname $0` > /dev/null
 HERE=`pwd`
@@ -8,12 +8,21 @@ popd > /dev/null
 
 retv=0
 
+ENV_PYTHON='{sys_executable}'
+
 which pre-commit >& /dev/null
 WHICH_RETV=$?
+"$ENV_PYTHON" -c 'import pre_commit.main' >& /dev/null
+ENV_PYTHON_RETV=$?
 python -c 'import pre_commit.main' >& /dev/null
 PYTHON_RETV=$?
 
-if [ $WHICH_RETV -ne 0 ] && [ $PYTHON_RETV -ne 0 ]; then
+
+if ((
+        (WHICH_RETV != 0) &&
+        (ENV_PYTHON_RETV != 0) &&
+        (PYTHON_RETV != 0)
+)); then
     echo '`pre-commit` not found.  Did you forget to activate your virtualenv?'
     exit 1
 fi
@@ -29,15 +38,18 @@ fi
 
 
 # Run pre-commit
-if [ $WHICH_RETV -eq 0 ]; then
+if ((WHICH_RETV == 0)); then
     pre-commit
     PRE_COMMIT_RETV=$?
+elif ((ENV_PYTHON_RETV == 0)); then
+    "$ENV_PYTHON" -m pre_commit.main
+    PRE_COMMIT_RETV=$?
 else
     python -m pre_commit.main
     PRE_COMMIT_RETV=$?
 fi
 
-if [ $PRE_COMMIT_RETV -ne 0 ]; then
+if ((PRE_COMMIT_RETV != 0)); then
     retv=1
 fi
 

tests/commands/install_uninstall_test.py

@@ -2,11 +2,13 @@ from __future__ import absolute_import
 from __future__ import unicode_literals
 
 import io
+import mock
 import os
 import os.path
 import re
 import subprocess
 import stat
+import sys
 from plumbum import local
 
 from pre_commit.commands.install_uninstall import IDENTIFYING_HASH
@@ -53,7 +55,9 @@ def test_install_pre_commit(tmpdir_factory):
     assert os.path.exists(runner.pre_commit_path)
     pre_commit_contents = io.open(runner.pre_commit_path).read()
     pre_commit_script = resource_filename('pre-commit-hook')
-    expected_contents = io.open(pre_commit_script).read()
+    expected_contents = io.open(pre_commit_script).read().format(
+        sys_executable=sys.executable,
+    )
     assert pre_commit_contents == expected_contents
     stat_result = os.stat(runner.pre_commit_path)
     assert stat_result.st_mode & (stat.S_IXUSR | stat.S_IXGRP | stat.S_IXOTH)
@@ -76,12 +80,17 @@ def test_uninstall(tmpdir_factory):
     assert not os.path.exists(runner.pre_commit_path)
 
 
-def _get_commit_output(tmpdir_factory, touch_file='foo', home=None):
+def _get_commit_output(
+        tmpdir_factory,
+        touch_file='foo',
+        home=None,
+        env_base=os.environ,
+):
     local['touch'](touch_file)
     local['git']('add', touch_file)
     # Don't want to write to home directory
     home = home or tmpdir_factory.get()
-    env = dict(os.environ, **{'PRE_COMMIT_HOME': home})
+    env = dict(env_base, **{'PRE_COMMIT_HOME': home})
     return local['git'].run(
         ['commit', '-m', 'Commit!', '--allow-empty'],
         # git commit puts pre-commit to stderr
@@ -136,11 +145,12 @@ def test_install_idempotent(tmpdir_factory):
 def test_environment_not_sourced(tmpdir_factory):
     path = make_consuming_repo(tmpdir_factory, 'script_hooks_repo')
     with local.cwd(path):
-        assert install(Runner(path)) == 0
+        # Patch the executable to simulate rming virtualenv
+        with mock.patch.object(sys, 'executable', '/bin/false'):
+            assert install(Runner(path)) == 0
 
         ret, stdout, stderr = local['git'].run(
             ['commit', '--allow-empty', '-m', 'foo'],
-            # XXX: 'HOME' makes this test pass on OSX
             env={'HOME': os.environ['HOME']},
             retcode=None,
         )
@@ -362,3 +372,17 @@ def test_installs_hooks_with_hooks_True(
 
         assert ret == 0
         assert PRE_INSTALLED.match(output)
+
+
+def test_installed_from_venv(tmpdir_factory):
+    path = make_consuming_repo(tmpdir_factory, 'script_hooks_repo')
+    with local.cwd(path):
+        install(Runner(path))
+        # No environment so pre-commit is not on the path when running!
+        # Should still pick up the python from when we installed
+        ret, output = _get_commit_output(
+            tmpdir_factory,
+            env_base={'HOME': os.environ['HOME']},
+        )
+        assert ret == 0
+        assert NORMAL_PRE_COMMIT_RUN.match(output)