Wrap build_meta tests in a reusable test class

setuptools/tests/test_build_meta.py

@@ -6,7 +6,6 @@ import tarfile
 
 import pytest
 
-from setuptools.build_meta import build_sdist
 from .files import build_files
 from .textwrap import DALS
 from . import py2_only
@@ -103,42 +102,43 @@ defns = [
 ]
 
 
-@pytest.fixture(params=defns)
-def build_backend(tmpdir, request):
+class TestBuildMetaBackend:
+    backend_name = 'setuptools.build_meta'
+
+    def get_build_backend(self):
+        return BuildBackend(cwd='.', backend_name=self.backend_name)
+
+    @pytest.fixture(params=defns)
+    def build_backend(self, tmpdir, request):
         build_files(request.param, prefix=str(tmpdir))
         with tmpdir.as_cwd():
-        yield BuildBackend(cwd='.')
+            yield self.get_build_backend()
 
-
-def test_get_requires_for_build_wheel(build_backend):
+    def test_get_requires_for_build_wheel(self, build_backend):
         actual = build_backend.get_requires_for_build_wheel()
         expected = ['six', 'wheel']
         assert sorted(actual) == sorted(expected)
 
-
-def test_get_requires_for_build_sdist(build_backend):
+    def test_get_requires_for_build_sdist(self, build_backend):
         actual = build_backend.get_requires_for_build_sdist()
         expected = ['six']
         assert sorted(actual) == sorted(expected)
 
-
-def test_build_wheel(build_backend):
+    def test_build_wheel(self, build_backend):
         dist_dir = os.path.abspath('pip-wheel')
         os.makedirs(dist_dir)
         wheel_name = build_backend.build_wheel(dist_dir)
 
         assert os.path.isfile(os.path.join(dist_dir, wheel_name))
 
-
-def test_build_sdist(build_backend):
+    def test_build_sdist(self, build_backend):
         dist_dir = os.path.abspath('pip-sdist')
         os.makedirs(dist_dir)
         sdist_name = build_backend.build_sdist(dist_dir)
 
         assert os.path.isfile(os.path.join(dist_dir, sdist_name))
 
-
-def test_prepare_metadata_for_build_wheel(build_backend):
+    def test_prepare_metadata_for_build_wheel(self, build_backend):
         dist_dir = os.path.abspath('pip-dist-info')
         os.makedirs(dist_dir)
 
@@ -146,9 +146,8 @@ def test_prepare_metadata_for_build_wheel(build_backend):
 
         assert os.path.isfile(os.path.join(dist_dir, dist_info, 'METADATA'))
 
-
-@py2_only
-def test_prepare_metadata_for_build_wheel_with_str(build_backend):
+    @py2_only
+    def test_prepare_metadata_for_build_wheel_with_str(self, build_backend):
         dist_dir = os.path.abspath(str('pip-dist-info'))
         os.makedirs(dist_dir)
 
@@ -156,16 +155,14 @@ def test_prepare_metadata_for_build_wheel_with_str(build_backend):
 
         assert os.path.isfile(os.path.join(dist_dir, dist_info, 'METADATA'))
 
-
-def test_build_sdist_explicit_dist(build_backend):
+    def test_build_sdist_explicit_dist(self, build_backend):
         # explicitly specifying the dist folder should work
         # the folder sdist_directory and the ``--dist-dir`` can be the same
         dist_dir = os.path.abspath('dist')
         sdist_name = build_backend.build_sdist(dist_dir)
         assert os.path.isfile(os.path.join(dist_dir, sdist_name))
 
-
-def test_build_sdist_version_change(build_backend):
+    def test_build_sdist_version_change(self, build_backend):
         sdist_into_directory = os.path.abspath("out_sdist")
         os.makedirs(sdist_into_directory)
 
@@ -188,17 +185,17 @@ def test_build_sdist_version_change(build_backend):
         assert os.path.isfile(
             os.path.join(os.path.abspath("out_sdist"), sdist_name))
 
-
-def test_build_sdist_setup_py_exists(tmpdir_cwd):
+    def test_build_sdist_setup_py_exists(self, tmpdir_cwd):
         # If build_sdist is called from a script other than setup.py,
-    # ensure setup.py is include
+        # ensure setup.py is included
         build_files(defns[0])
-    targz_path = build_sdist("temp")
+
+        build_backend = self.get_build_backend()
+        targz_path = build_backend.build_sdist("temp")
         with tarfile.open(os.path.join("temp", targz_path)) as tar:
             assert any('setup.py' in name for name in tar.getnames())
 
-
-def test_build_sdist_setup_py_manifest_excluded(tmpdir_cwd):
+    def test_build_sdist_setup_py_manifest_excluded(self, tmpdir_cwd):
         # Ensure that MANIFEST.in can exclude setup.py
         files = {
             'setup.py': DALS("""
@@ -214,12 +211,13 @@ def test_build_sdist_setup_py_manifest_excluded(tmpdir_cwd):
         }
 
         build_files(files)
-    targz_path = build_sdist("temp")
+
+        build_backend = self.get_build_backend()
+        targz_path = build_backend.build_sdist("temp")
         with tarfile.open(os.path.join("temp", targz_path)) as tar:
             assert not any('setup.py' in name for name in tar.getnames())
 
-
-def test_build_sdist_builds_targz_even_if_zip_indicated(tmpdir_cwd):
+    def test_build_sdist_builds_targz_even_if_zip_indicated(self, tmpdir_cwd):
         files = {
             'setup.py': DALS("""
                 __import__('setuptools').setup(
@@ -235,4 +233,6 @@ def test_build_sdist_builds_targz_even_if_zip_indicated(tmpdir_cwd):
         }
 
         build_files(files)
-    build_sdist("temp")
+
+        build_backend = self.get_build_backend()
+        build_backend.build_sdist("temp")