Add clean wrapper for calling python in venv

venv_tools/__init__.py

@@ -8,6 +8,7 @@
 :copyright: (c) 2014 by James Tocknell.
 :license: BSD, see LICENSE for more details.
 """
+from logging import getLogger
 import os
 import os.path
 import tempfile
@@ -18,7 +19,7 @@
 
 from ._utils import (
     pathprepend, get_default_venv_builder, is_venv, BIN_DIR, PYTHON_FILENAME,
-    abspath_python_exe,
+    abspath_python_exe, run_python_with_args
 )
 
 from ._version import get_versions
@@ -27,6 +28,7 @@
 
 
 DEFAULT_INSTALL_COMMAND = "{python} -m pip install {package}"
+log = getLogger(__name__)
 
 
 class Venv(object):
@@ -77,13 +79,15 @@ def __enter__(self):
             venv = self._venv_builder(**self._kwargs)
             venv.create(self.env_dir)
         pathprepend(os.path.join(self.env_dir, BIN_DIR), "PATH")
+        log.debug("PATH is now %s", os.environ["PATH"])
         if self._python_home is not None:
             os.environ.pop("PYTHONHOME")
         os.environ["VIRTUAL_ENV"] = self.env_dir
         return self
 
     def __exit__(self, exc_type, exc_value, traceback):
         os.environ["PATH"] = self._old_path
+        log.debug("PATH is now %s", os.environ["PATH"])
         if self._python_home is not None:
             os.environ["PYTHONHOME"] = self._python_home
         os.environ.pop("VIRTUAL_ENV")
@@ -116,32 +120,31 @@ def install_command(self):
     def install_command(self, new_cmd):
         self._install_command = new_cmd
 
-    def call_python_file(self, filename):
+    def call_python_file(self, filename, *args, **kwargs):
         """
         Call a python file with the python interpreter associated with this
         virtualenv.
         """
-        return subprocess.check_output(
-            [self.python_exe, filename], stderr=subprocess.STDOUT
+        return run_python_with_args(
+            python_exe=self.python_exe, script=filename, args=args, **kwargs
         )
 
-    def call_python_module(self, module_name, *args):
+    def call_python_module(self, module_name, *args, **kwargs):
         """
         Call a python module with the python interpreter associated with this
         virtualenv.
         """
-        return subprocess.check_output(
-            [self.python_exe, '-m', module_name].append(args),
-            stderr=subprocess.STDOUT
+        return run_python_with_args(
+            python_exe=self.python_exe, module=module_name, args=args, **kwargs
         )
 
-    def call_python_code(self, code):
+    def call_python_code(self, code, *args, **kwargs):
         """
         Call some python code with the python interpreter associated with this
         virtualenv.
         """
-        return subprocess.check_output(
-            [self.python_exe, '-c', code], stderr=subprocess.STDOUT
+        return run_python_with_args(
+            python_exe=self.python_exe, code=code, args=args, **kwargs
         )
 
     def install_package(self, package):

venv_tools/_utils.py

@@ -8,23 +8,27 @@
 :copyright: (c) 2014 by James Tocknell.
 :license: BSD, see LICENSE for more details.
 """
+from logging import getLogger
 import os
 import os.path as pth
+import subprocess
 import sys
 
 from ._venv_builders import VirtualenvBuilder
 
 BIN_DIR = "Scripts" if sys.platform == 'win32' else "bin"
 PYTHON_FILENAME = "python.exe" if sys.platform == 'win32' else "python"
 PYVENV_FILENAME = "pyvenv.cfg"
-ACTIVATE_FILENAMES = [
+ACTIVATE_FILENAMES = (
     "activate",
     "activate.csh",
     "activate.fish",
     "activate_this.py",
     "activate.bat",
     "activate.ps1",
-]
+)
+
+log = getLogger(__name__)
 
 
 def pathremove(dirname, path):
@@ -149,3 +153,35 @@ def abspath_path_executable(executable):
         if is_executable(full_path):
             return full_path
     raise FileNotFoundError(executable + " is not on current path")
+
+
+def run_python_with_args(
+    *, python_exe, args=None, module=None, code=None, script=None,
+    input=None,  # pylint: disable=redefined-builtin
+    stdin=None, stdout=subprocess.PIPE, stderr=subprocess.PIPE, timeout=None
+):
+    """
+    Wrapper around subprocess.run for calling python interpreter.
+    """
+    if sum(1 for kw in (module, code, script) if kw is not None) != 1:
+        raise RuntimeError(
+            "One of module, code or script should be provided."
+        )
+
+    cmd_list = [python_exe]
+    if module is not None:
+        cmd_list.extend(['-m', module])
+    if code is not None:
+        cmd_list.extend(['-c', code])
+    if script is not None:
+        cmd_list.append(script)
+
+    if args is not None:
+        cmd_list.extend(args)
+
+    log.debug("Running command %s", cmd_list)
+
+    return subprocess.run(
+        cmd_list, input=input, stdin=stdin, stdout=stdout, stderr=stderr,
+        timeout=timeout, shell=False, universal_newlines=True, check=True
+    )