Test that setuptools gets capped also with -I

Author: astrojuanlu

readthedocs/rtd_tests/tests/test_doc_building.py

@@ -1243,6 +1243,44 @@ def test_install_core_requirements_sphinx(self, checkout_path):
         args = self.pip_install_args + requirements
         self.assertArgsStartsWith(args, calls[1])
 
+    @mock.patch('readthedocs.doc_builder.config.load_config')
+    @patch('readthedocs.projects.models.Project.checkout_path')
+    def test_install_core_requirements_sphinx_system_packages_caps_setuptools(self, checkout_path, load_config):
+        config_data = {
+            'python': {
+                'use_system_site_packages': True,
+            },
+        }
+        load_config.side_effect = create_load(config_data)
+        config = load_yaml_config(self.version_sphinx)
+
+        tmpdir = tempfile.mkdtemp()
+        checkout_path.return_value = tmpdir
+        python_env = Virtualenv(
+            version=self.version_sphinx,
+            build_env=self.build_env_mock,
+            config=config,
+        )
+        python_env.install_core_requirements()
+        requirements_sphinx = [
+            'commonmark',
+            'recommonmark',
+            'sphinx',
+            'sphinx-rtd-theme',
+            'readthedocs-sphinx-ext',
+            'setuptools<58.3.0',
+        ]
+
+        self.assertEqual(self.build_env_mock.run.call_count, 2)
+        calls = self.build_env_mock.run.call_args_list
+
+        core_args = self.pip_install_args + ['pip', 'setuptools<58.3.0']
+        self.assertArgsStartsWith(core_args, calls[0])
+
+        requirements = self.base_requirements + requirements_sphinx
+        args = self.pip_install_args + ['-I'] + requirements
+        self.assertArgsStartsWith(args, calls[1])
+
     @patch('readthedocs.projects.models.Project.checkout_path')
     def test_install_core_requirements_mkdocs(self, checkout_path):
         tmpdir = tempfile.mkdtemp()