tests_require=['pytest', 'pytest-cov'] breaks setuptools.setup

[bb-migration]

Originally reported by: slashfoo (Bitbucket: slashfoo, GitHub: slashfoo)

---

(test)[20:24:14] [jamiel@moeka:masterskel/] $ python setup.py coverage
This command (coverage) requires the installation of pytest-cov
running coverage
Searching for pytest-cov
Reading https://pypi.python.org/simple/pytest-cov/
Best match: pytest-cov 1.6
Downloading https://pypi.python.org/packages/source/p/pytest-cov/pytest-cov-1.6.tar.gz#md5=6da54d74bde9d200de45068ba2ea637a
Processing pytest-cov-1.6.tar.gz
Writing /tmp/easy_install-xvMxzZ/pytest-cov-1.6/setup.cfg
Running pytest-cov-1.6/setup.py -q bdist_egg --dist-dir /tmp/easy_install-xvMxzZ/pytest-cov-1.6/egg-dist-tmp-BGJIES

Installed /home/jamiel/dev/masterskel/pytest_cov-1.6-py2.7.egg
Searching for pytest
Best match: pytest cov-1.6
Downloading https://pypi.python.org/packages/source/p/pytest-cov/pytest-cov-1.6.tar.gz#md5=6da54d74bde9d200de45068ba2ea637a
Processing pytest-cov-1.6.tar.gz
Writing /tmp/easy_install-EweVbo/pytest-cov-1.6/setup.cfg
Running pytest-cov-1.6/setup.py -q bdist_egg --dist-dir /tmp/easy_install-EweVbo/pytest-cov-1.6/egg-dist-tmp-zxCrHa

Installed /home/jamiel/dev/masterskel/pytest_cov-1.6-py2.7.egg
Traceback (most recent call last):
  File "setup.py", line 203, in <module>
    zip_safe=False,
  File "/usr/lib/python2.7/distutils/core.py", line 151, in setup
    dist.run_commands()
  File "/usr/lib/python2.7/distutils/dist.py", line 953, in run_commands
    self.run_command(cmd)
  File "/usr/lib/python2.7/distutils/dist.py", line 972, in run_command
    cmd_obj.run()
  File "/home/jamiel/.virtualenvs/test/local/lib/python2.7/site-packages/setuptools/command/test.py", line 130, in run
    self.distribution.fetch_build_eggs(self.distribution.tests_require)
  File "/home/jamiel/.virtualenvs/test/local/lib/python2.7/site-packages/setuptools/dist.py", line 264, in fetch_build_eggs
    replace_conflicting=True
  File "/home/jamiel/.virtualenvs/test/local/lib/python2.7/site-packages/pkg_resources.py", line 588, in resolve
    raise DistributionNotFound(req)
pkg_resources.DistributionNotFound: pytest

since 'pytest-cov' depends on 'pytest', making tests_require=['pytest-cov'] fixes the issue, same if it is tests_require=['pytest-cov', 'pytest'].

Setting a breakpoint on ${HOME}/.virtualenvs/slashpyenv/lib/python3.4/site-packages/pkg_resources.py:620 (replace for your path to pkg_sources.py) shows:

dist = best[req.key] = env.best_match(req, ws, installer)

after running on for req = Requirement.parse('pytest-cov'), when I run !env.best_match(Requirement.parse('pytest'), ws, installer) it returns the best match to be 'pytest-cov 1.6' and exits.

note: In the report you see 3.4 in the outputs ect... but this is also present in 2.7.

---

• Bitbucket: https://bitbucket.org/pypa/setuptools/issue/196

[bb-migration]

Original comment by jkbr (Bitbucket: jkbr, GitHub: jkbr):

---

Got the same problem with

#!python

tests_require = [
   'pytest',
   'pytest-httpbin',

]

Reversing the order fixed it.

[bb-migration]

Original comment by pbn (Bitbucket: pbn, GitHub: pbn):

---

I am seeing the same problem here with:

```
#!python

install_require = [
    'pytest',
    'pytest-instafail',
]
```

[bb-migration]

Original comment by jaraco (Bitbucket: jaraco, GitHub: jaraco):

---

It looks like pytest-cov is being matched as the "cov" version of pytest, and so is fulfilling the requirement of "pytest". I seem to recall somewhere that setuptools discourages the use of dashes in package names, probably for this reason.

I don't yet know what to recommend here other than to follow the indicated workaround.

[bb-migration]

Original comment by jaraco (Bitbucket: jaraco, GitHub: jaraco):

---

Issue #370 was marked as a duplicate of this issue.

[AlexanderMartynoff]

Hello everyone, who can say when this bug will be resolved?

[jaraco]

I don't think it will ever be fixed. Setup requires and easy install are deprecated in favor of PEP 518 in pip and tools like tox and pip. I recommend avoiding easy install and setup requires as much as possible, use the workaround where necesaary.

[Juanlu001]

I recommend avoiding easy install and setup requires as much as possible, use the workaround where necesaary.

What about tests_require? Is there a PEP 518 equivalent yet?

[benoit-pierre]

Just encountered this issue today while looking at another bug. It looks like it's caused by reusing the easy_install command instead of creating a new one every time:

diff --git a/setuptools/dist.py b/setuptools/dist.py
index fa0b5eb4..6cd04d6e 100644
--- a/setuptools/dist.py
+++ b/setuptools/dist.py
@@ -482,36 +482,30 @@ class Distribution(Distribution_parse_config_files, _Distribution):
 
     def fetch_build_egg(self, req):
         """Fetch an egg needed for building"""
-
-        try:
-            cmd = self._egg_fetcher
-            cmd.package_index.to_scan = []
-        except AttributeError:
-            from setuptools.command.easy_install import easy_install
-            dist = self.__class__({'script_args': ['easy_install']})
-            dist.parse_config_files()
-            opts = dist.get_option_dict('easy_install')
-            keep = (
-                'find_links', 'site_dirs', 'index_url', 'optimize',
-                'site_dirs', 'allow_hosts'
-            )
-            for key in list(opts):
-                if key not in keep:
-                    del opts[key]  # don't use any other settings
-            if self.dependency_links:
-                links = self.dependency_links[:]
-                if 'find_links' in opts:
-                    links = opts['find_links'][1].split() + links
-                opts['find_links'] = ('setup', links)
-            install_dir = self.get_egg_cache_dir()
-            cmd = easy_install(
-                dist, args=["x"], install_dir=install_dir,
-                exclude_scripts=True,
-                always_copy=False, build_directory=None, editable=False,
-                upgrade=False, multi_version=True, no_report=True, user=False
-            )
-            cmd.ensure_finalized()
-            self._egg_fetcher = cmd
+        from setuptools.command.easy_install import easy_install
+        dist = self.__class__({'script_args': ['easy_install']})
+        dist.parse_config_files()
+        opts = dist.get_option_dict('easy_install')
+        keep = (
+            'find_links', 'site_dirs', 'index_url', 'optimize',
+            'site_dirs', 'allow_hosts'
+        )
+        for key in list(opts):
+            if key not in keep:
+                del opts[key]  # don't use any other settings
+        if self.dependency_links:
+            links = self.dependency_links[:]
+            if 'find_links' in opts:
+                links = opts['find_links'][1].split() + links
+            opts['find_links'] = ('setup', links)
+        install_dir = self.get_egg_cache_dir()
+        cmd = easy_install(
+            dist, args=["x"], install_dir=install_dir,
+            exclude_scripts=True,
+            always_copy=False, build_directory=None, editable=False,
+            upgrade=False, multi_version=True, no_report=True, user=False
+        )
+        cmd.ensure_finalized()
         return cmd.easy_install(req)
 
     def _set_global_opts_from_features(self):

Working on adding a test before making a PR.

[jaraco]

The fix was released with 36.4.0.