Give markers chance to remove incompat wheel links

`pip install -r reqs.txt` was failing when the requirements file includes
an unsupported wheel, regardless of whether it is conditionally removed
by a marker. This patch fixes that issue.

Additionally, this patch makes pip check local file wheels for
compatibility. Previously, a requirements file could include a path
to a valid wheel for any platform and pip would happily install it.

CHANGES.txt

@@ -2,6 +2,9 @@
 
 * Fix a regression on systems with uninitialized locale (:issue:`3575`).
 
+* Use environment markers to filter packages before determining if a
+  required wheel is supported. Solves (:issue:`3254`).
+
 
 **8.1.1 (2016-03-17)**
 

pip/req/req_install.py

@@ -27,7 +27,7 @@ import pip.wheel
 from pip.compat import native_str, get_stdlib, WINDOWS
 from pip.download import is_url, url_to_path, path_to_url, is_archive_file
 from pip.exceptions import (
-    InstallationError, UninstallationError, UnsupportedWheel,
+    InstallationError, UninstallationError,
 )
 from pip.locations import (
     bin_py, running_under_virtualenv, PIP_DELETE_MARKER_FILENAME, bin_user,
@@ -210,11 +210,6 @@ class InstallRequirement(object):
             # wheel file
             if link.is_wheel:
                 wheel = Wheel(link.filename)  # can raise InvalidWheelFilename
-                if not wheel.supported():
-                    raise UnsupportedWheel(
-                        "%s is not a supported wheel on this platform." %
-                        wheel.filename
-                    )
                 req = "%s==%s" % (wheel.name, wheel.version)
             else:
                 # set the req to the egg fragment.  when it's not there, this

pip/req/req_set.py

@@ -21,7 +21,7 @@ from pip.utils import (
 from pip.utils.hashes import MissingHashes
 from pip.utils.logging import indent_log
 from pip.vcs import vcs
-
+from pip.wheel import Wheel
 
 logger = logging.getLogger(__name__)
 
@@ -227,6 +227,16 @@ class RequirementSet(object):
                            install_req.markers)
             return []
 
+        # This check has to come after we filter requirements with the
+        # environment markers.
+        if install_req.link and install_req.link.is_wheel:
+            wheel = Wheel(install_req.link.filename)
+            if not wheel.supported():
+                raise InstallationError(
+                    "%s is not a supported wheel on this platform." %
+                    wheel.filename
+                )
+
         install_req.as_egg = self.as_egg
         install_req.use_user_site = self.use_user_site
         install_req.target_dir = self.target_dir

tests/functional/test_install_reqs.py

@@ -457,3 +457,41 @@ def test_install_distribution_union_conflicting_extras(script, data):
                                       expect_error=True)
     assert 'installed' not in result.stdout
     assert "Conflict" in result.stderr
+
+
+def test_install_unsupported_wheel_link_with_marker(script, data):
+    script.scratch_path.join("with-marker.txt").write(
+        textwrap.dedent("""\
+            %s; %s
+        """) %
+        (
+            'https://github.com/a/b/c/asdf-1.5.2-cp27-none-xyz.whl',
+            'sys_platform == "xyz"'
+        )
+    )
+    result = script.pip(
+        'install', '-r', script.scratch_path / 'with-marker.txt',
+        expect_error=False,
+        expect_stderr=True,
+    )
+
+    s = "Ignoring asdf: markers %r don't match your environment" %\
+        u'sys_platform == "xyz"'
+    assert s in result.stderr
+    assert len(result.files_created) == 0
+
+
+def test_install_unsupported_wheel_file(script, data):
+    # Trying to install a local wheel with an incompatible version/type
+    # should fail.
+    script.scratch_path.join("wheel-file.txt").write(textwrap.dedent("""\
+        %s
+        """ % data.packages.join("simple.dist-0.1-py1-none-invalid.whl")))
+    result = script.pip(
+        'install', '-r', script.scratch_path / 'wheel-file.txt',
+        expect_error=True,
+        expect_stderr=True,
+    )
+    assert ("simple.dist-0.1-py1-none-invalid.whl is not a supported " +
+            "wheel on this platform" in result.stderr)
+    assert len(result.files_created) == 0

tests/unit/test_req.py

@@ -8,7 +8,7 @@ import pytest
 from mock import Mock, patch, mock_open
 from pip.commands.install import InstallCommand
 from pip.exceptions import (PreviousBuildDirError, InvalidWheelFilename,
-                            InstallationError, UnsupportedWheel, HashErrors)
+                            InstallationError, HashErrors)
 from pip.download import path_to_url, PipSession
 from pip.index import PackageFinder
 from pip.req import (InstallRequirement, RequirementSet, Requirements)
@@ -301,6 +301,20 @@ def test_egg_info_data(file_contents, expected):
 
 
 class TestInstallRequirement(object):
+    def setup(self):
+        self.tempdir = tempfile.mkdtemp()
+
+    def teardown(self):
+        shutil.rmtree(self.tempdir, ignore_errors=True)
+
+    def basic_reqset(self, **kwargs):
+        return RequirementSet(
+            build_dir=os.path.join(self.tempdir, 'build'),
+            src_dir=os.path.join(self.tempdir, 'src'),
+            download_dir=None,
+            session=PipSession(),
+            **kwargs
+        )
 
     def test_url_with_query(self):
         """InstallRequirement should strip the fragment, but not the query."""
@@ -309,11 +323,29 @@ class TestInstallRequirement(object):
         req = InstallRequirement.from_line(url + fragment)
         assert req.link.url == url + fragment, req.link
 
-    def test_unsupported_wheel_requirement_raises(self):
-        with pytest.raises(UnsupportedWheel):
-            InstallRequirement.from_line(
-                'peppercorn-0.4-py2.py3-bogus-any.whl',
-            )
+    def test_unsupported_wheel_link_requirement_raises(self):
+        reqset = self.basic_reqset()
+        req = InstallRequirement.from_line(
+            'https://whatever.com/peppercorn-0.4-py2.py3-bogus-any.whl',
+        )
+        assert req.link is not None
+        assert req.link.is_wheel
+        assert req.link.scheme == "https"
+
+        with pytest.raises(InstallationError):
+            reqset.add_requirement(req)
+
+    def test_unsupported_wheel_local_file_requirement_raises(self, data):
+        reqset = self.basic_reqset()
+        req = InstallRequirement.from_line(
+            data.packages.join('simple.dist-0.1-py1-none-invalid.whl'),
+        )
+        assert req.link is not None
+        assert req.link.is_wheel
+        assert req.link.scheme == "file"
+
+        with pytest.raises(InstallationError):
+            reqset.add_requirement(req)
 
     def test_installed_version_not_installed(self):
         req = InstallRequirement.from_line('simple-0.1-py2.py3-none-any.whl')