invoke pytest directly instead of through the setup.py file

.travis.yml

@@ -8,7 +8,7 @@ env:
 install:
   - pip install -U setuptools
   # install_requires
-  - pip install -U distlib EmPy pytest-rerunfailures pytest pytest-cov pytest-repeat pytest-runner
+  - pip install -U distlib EmPy pytest-rerunfailures pytest pytest-cov pytest-repeat
   # additional tests_require
   - pip install -U flake8-blind-except flake8-builtins flake8-class-newline flake8-comprehensions flake8-deprecated flake8-docstrings flake8-quotes pep8-naming pylint scspell3k
   # for uploading the coverage information to codecov

colcon_core/task/python/test/pytest.py

@@ -13,7 +13,6 @@
 from colcon_core.task.python.test import has_test_dependency
 from colcon_core.task.python.test import PythonTestingStepExtensionPoint
 from colcon_core.verb.test import logger
-from pkg_resources import iter_entry_points
 from pkg_resources import parse_version
 
 
@@ -29,9 +28,10 @@ def __init__(self):  # noqa: D107
         satisfies_version(
             PythonTestingStepExtensionPoint.EXTENSION_POINT_VERSION, '^1.0')
 
-        entry_points = iter_entry_points('distutils.commands', name='pytest')
-        if not list(entry_points):
-            raise SkipExtensionException("'pytest-runner' not found")
+        try:
+            import pytest  # noqa: F401
+        except ImportError:
+            raise SkipExtensionException("'pytest' not found")
 
     def add_arguments(self, *, parser):  # noqa: D102
         parser.add_argument(
@@ -49,11 +49,7 @@ def match(self, context, env, setup_py_data):  # noqa: D102
         return has_test_dependency(setup_py_data, 'pytest')
 
     async def step(self, context, env, setup_py_data):  # noqa: D102
-        cmd = [
-            sys.executable,
-            'setup.py', 'pytest',
-            'egg_info', '--egg-base', context.args.build_base,
-        ]
+        cmd = [sys.executable, '-m', 'pytest']
         junit_xml_path = Path(
             context.args.test_result_base
             if context.args.test_result_base

debian/patches/setup.cfg.patch

@@ -16,6 +16,6 @@ Author: Dirk Thomas <[email protected]>
 +	# would result in a runtime error by pkg_resources
 +	# pytest-repeat
 +	# pytest-rerunfailures
- 	pytest-runner
  	setuptools>=30.3.0
  packages = find:
+ tests_require = 

setup.cfg

@@ -36,7 +36,6 @@ install_requires =
   pytest-cov
   pytest-repeat
   pytest-rerunfailures
-  pytest-runner
   setuptools>=30.3.0
 packages = find:
 tests_require =

stdeb.cfg

@@ -1,5 +1,5 @@
 [colcon-core]
 No-Python2:
-Depends3: python3-distlib, python3-empy, python3-pytest, python3-pytest-cov, python3-pytest-runner, python3-setuptools
+Depends3: python3-distlib, python3-empy, python3-pytest, python3-pytest-cov, python3-setuptools
 Suite: xenial bionic focal stretch buster
 X-Python3-Version: >= 3.5