In test command, add installed eggs to PYTHONPATH when invoking tests so that...

In test command, add installed eggs to PYTHONPATH when invoking tests so that subprocesses will also have the dependencies available. Fixes #794.

CHANGES.rst

@@ -2,6 +2,13 @@
 CHANGES
 =======
 
+v27.3.0
+-------
+
+* #794: In test command, add installed eggs to PYTHONPATH
+  when invoking tests so that subprocesses will also have the
+  dependencies available.
+
 v27.2.0
 -------
 

setuptools/command/test.py

+import os
+import operator
 import sys
 import contextlib
 from distutils.errors import DistutilsOptionError
 from unittest import TestLoader
 
 from setuptools.extern import six
-from setuptools.extern.six.moves import map
+from setuptools.extern.six.moves import map, filter
 
 from pkg_resources import (resource_listdir, resource_exists, normalize_path,
                            working_set, _namespace_packages,
@@ -112,7 +114,7 @@ class test(Command):
             func()
 
     @contextlib.contextmanager
-    def project_on_sys_path(self):
+    def project_on_sys_path(self, include_dists=[]):
         with_2to3 = six.PY3 and getattr(self.distribution, 'use_2to3', False)
 
         if with_2to3:
@@ -144,23 +146,57 @@ class test(Command):
         old_modules = sys.modules.copy()
 
         try:
-            sys.path.insert(0, normalize_path(ei_cmd.egg_base))
+            project_path = normalize_path(ei_cmd.egg_base)
+            sys.path.insert(0, project_path)
             working_set.__init__()
             add_activation_listener(lambda dist: dist.activate())
             require('%s==%s' % (ei_cmd.egg_name, ei_cmd.egg_version))
-            yield
+            with self.paths_on_pythonpath([project_path]):
+                yield
         finally:
             sys.path[:] = old_path
             sys.modules.clear()
             sys.modules.update(old_modules)
             working_set.__init__()
 
+    @staticmethod
+    @contextlib.contextmanager
+    def paths_on_pythonpath(paths):
+        """
+        Add the indicated paths to the head of the PYTHONPATH environment
+        variable so that subprocesses will also see the packages at
+        these paths.
+
+        Do this in a context that restores the value on exit.
+        """
+        nothing = object()
+        orig_pythonpath = os.environ.get('PYTHONPATH', nothing)
+        current_pythonpath = os.environ.get('PYTHONPATH', '')
+        try:
+            prefix = os.pathsep.join(paths)
+            to_join = filter(None, [prefix, current_pythonpath])
+            new_path = os.pathsep.join(to_join)
+            if new_path:
+                os.environ['PYTHONPATH'] = new_path
+            yield
+        finally:
+            if orig_pythonpath is nothing:
+                os.environ.pop('PYTHONPATH', None)
+            else:
+                os.environ['PYTHONPATH'] = orig_pythonpath
+
     def run(self):
+        installed_dists = []
         if self.distribution.install_requires:
-            self.distribution.fetch_build_eggs(
-                self.distribution.install_requires)
+            installed_dists.extend(
+                self.distribution.fetch_build_eggs(
+                    self.distribution.install_requires,
+                ))
         if self.distribution.tests_require:
-            self.distribution.fetch_build_eggs(self.distribution.tests_require)
+            installed_dists.extend(
+                    self.distribution.fetch_build_eggs(
+                            self.distribution.tests_require,
+                ))
 
         cmd = ' '.join(self._argv)
         if self.dry_run:
@@ -168,8 +204,11 @@ class test(Command):
             return
 
         self.announce('running "%s"' % cmd)
-        with self.project_on_sys_path():
-            self.run_tests()
+
+        paths = map(operator.attrgetter('location'), installed_dists)
+        with self.paths_on_pythonpath(paths):
+            with self.project_on_sys_path():
+                self.run_tests()
 
     def run_tests(self):
         # Purge modules under test from sys.modules. The test loader will

setuptools/dist.py

@@ -362,6 +362,7 @@ class Distribution(_Distribution):
         )
         for dist in resolved_dists:
             pkg_resources.working_set.add(dist, replace=True)
+        return resolved_dists
 
     def finalize_options(self):
         _Distribution.finalize_options(self)