Merge pull request #1127 from benoit-pierre/workaround_easy_install_bug

workaround easy_install bug

3 files changed, 74 insertions, 30 deletions

diff --git a/CHANGES.rst b/CHANGES.rst
index 24a3e4d0..9b9d5fe1 100644
--- a/CHANGES.rst
+++ b/CHANGES.rst
@@ -8,6 +8,10 @@ v36.4.0
 * #1068: Sort files and directories when building eggs for
   deterministic order.
 
+* #196: Remove caching of easy_install command in fetch_build_egg.
+  Fixes issue where ``pytest-runner-N.N`` would satisfy the installation
+  of ``pytest``.
+
 v36.3.0
 -------
 
diff --git a/setuptools/dist.py b/setuptools/dist.py
index 084641a8..a2ca8795 100644
--- a/setuptools/dist.py
+++ b/setuptools/dist.py
@@ -495,36 +495,30 @@ 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):
diff --git a/setuptools/tests/test_dist.py b/setuptools/tests/test_dist.py
new file mode 100644
index 00000000..435ffec0
--- /dev/null
+++ b/setuptools/tests/test_dist.py
@@ -0,0 +1,46 @@
+from setuptools import Distribution
+from setuptools.extern.six.moves.urllib.request import pathname2url
+from setuptools.extern.six.moves.urllib_parse import urljoin
+
+from .textwrap import DALS
+from .test_easy_install import make_nspkg_sdist
+
+
+def test_dist_fetch_build_egg(tmpdir):
+    """
+    Check multiple calls to `Distribution.fetch_build_egg` work as expected.
+    """
+    index = tmpdir.mkdir('index')
+    index_url = urljoin('file://', pathname2url(str(index)))
+    def sdist_with_index(distname, version):
+        dist_dir = index.mkdir(distname)
+        dist_sdist = '%s-%s.tar.gz' % (distname, version)
+        make_nspkg_sdist(str(dist_dir.join(dist_sdist)), distname, version)
+        with dist_dir.join('index.html').open('w') as fp:
+            fp.write(DALS(
+                '''
+                <!DOCTYPE html><html><body>
+                <a href="{dist_sdist}" rel="internal">{dist_sdist}</a><br/>
+                </body></html>
+                '''
+            ).format(dist_sdist=dist_sdist))
+    sdist_with_index('barbazquux', '3.2.0')
+    sdist_with_index('barbazquux-runner', '2.11.1')
+    with tmpdir.join('setup.cfg').open('w') as fp:
+        fp.write(DALS(
+            '''
+            [easy_install]
+            index_url = {index_url}
+            '''
+        ).format(index_url=index_url))
+    reqs = '''
+    barbazquux-runner
+    barbazquux
+    '''.split()
+    with tmpdir.as_cwd():
+        dist = Distribution()
+        resolved_dists = [
+            dist.fetch_build_egg(r)
+            for r in reqs
+        ]
+    assert [dist.key for dist in resolved_dists if dist] == reqs