functional test for --install-option in a requirements file

Author: qwcode

tests/functional/test_install_reqs.py

@@ -169,3 +169,16 @@ def test_install_local_editable_with_subdirectory(script):
     )
 
     result.assert_installed('version-subpkg', sub_dir='version_subdir')
+
+
+def test_install_option_in_requirements_file(script, data, virtualenv):
+    virtualenv.system_site_packages = True
+    script.scratch_path.join("reqs.txt").write(textwrap.dedent("""\
+        simple --install-option='--user'
+        """))
+    result = script.pip(
+        'install', '--no-index', '-f', data.find_links, '-r',
+        script.scratch_path / 'reqs.txt'
+    )
+    package_dir = script.user_site / 'simple'
+    assert package_dir in result.files_created