Add mock server wrapper and replace network calls in a test

Author: chrahunt

tests/conftest.py

@@ -6,18 +6,27 @@
 import shutil
 import subprocess
 import sys
+from contextlib import contextmanager
 
 import pytest
 import six
+from pip._vendor.contextlib2 import ExitStack
 from setuptools.wheel import Wheel
 
 from pip._internal.main import main as pip_entry_point
+from pip._internal.utils.typing import MYPY_CHECK_RUNNING
 from tests.lib import DATA_DIR, SRC_DIR, TestData
 from tests.lib.certs import make_tls_cert, serialize_cert, serialize_key
 from tests.lib.path import Path
 from tests.lib.scripttest import PipTestEnvironment
+from tests.lib.server import make_mock_server, server_running
 from tests.lib.venv import VirtualEnvironment
 
+if MYPY_CHECK_RUNNING:
+    from typing import Dict, Iterable
+
+    from tests.lib.server import MockServer as _MockServer, Responder
+
 
 def pytest_addoption(parser):
     parser.addoption(
@@ -404,3 +413,60 @@ def factory():
         return str(output_path)
 
     return factory
+
+
+class MockServer(object):
+    def __init__(self, server):
+        # type: (_MockServer) -> None
+        self._server = server
+        self._running = False
+        self.context = ExitStack()
+
+    @property
+    def port(self):
+        return self._server.port
+
+    @property
+    def host(self):
+        return self._server.host
+
+    def set_responses(self, responses):
+        # type: (Iterable[Responder]) -> None
+        assert not self._running, "responses cannot be set on running server"
+        self._server.mock.side_effect = responses
+
+    def start(self):
+        # type: () -> None
+        assert not self._running, "running server cannot be started"
+        self.context.enter_context(server_running(self._server))
+        self.context.enter_context(self._set_running())
+
+    @contextmanager
+    def _set_running(self):
+        self._running = True
+        try:
+            yield
+        finally:
+            self._running = False
+
+    def stop(self):
+        # type: () -> None
+        assert self._running, "idle server cannot be stopped"
+        self.context.close()
+
+    def get_requests(self):
+        # type: () -> Dict[str, str]
+        """Get environ for each received request.
+        """
+        assert not self._running, "cannot get mock from running server"
+        return [
+            call.args[0] for call in self._server.mock.call_args_list
+        ]
+
+
+@pytest.fixture
+def mock_server():
+    server = make_mock_server()
+    test_server = MockServer(server)
+    with test_server.context:
+        yield test_server

tests/functional/test_install_config.py

@@ -4,6 +4,8 @@
 
 import pytest
 
+from tests.lib.server import file_response, package_page
+
 
 def test_options_from_env_vars(script):
     """
@@ -122,46 +124,55 @@ def test_command_line_appends_correctly(script, data):
     ), 'stdout: {}'.format(result.stdout)
 
 
-@pytest.mark.network
-def test_config_file_override_stack(script, virtualenv):
+def test_config_file_override_stack(
+    script, virtualenv, mock_server, shared_data
+):
     """
     Test config files (global, overriding a global config with a
     local, overriding all with a command line flag).
     """
+    mock_server.set_responses([
+        package_page({}),
+        package_page({}),
+        package_page({"INITools-0.2.tar.gz": "/files/INITools-0.2.tar.gz"}),
+        file_response(shared_data.packages.joinpath("INITools-0.2.tar.gz")),
+    ])
+    mock_server.start()
+    base_address = "http://{}:{}".format(mock_server.host, mock_server.port)
+
     config_file = script.scratch_path / "test-pip.cfg"
 
     # set this to make pip load it
     script.environ['PIP_CONFIG_FILE'] = str(config_file)
+
     config_file.write_text(textwrap.dedent("""\
         [global]
-        index-url = https://download.zope.org/ppix
-        """))
-    result = script.pip('install', '-vvv', 'INITools', expect_error=True)
-    assert (
-        "Getting page https://download.zope.org/ppix/initools" in result.stdout
-    )
+        index-url = {}/simple1
+        """.format(base_address)))
+    script.pip('install', '-vvv', 'INITools', expect_error=True)
     virtualenv.clear()
+
     config_file.write_text(textwrap.dedent("""\
         [global]
-        index-url = https://download.zope.org/ppix
+        index-url = {address}/simple1
         [install]
-        index-url = https://pypi.gocept.com/
-        """))
-    result = script.pip('install', '-vvv', 'INITools', expect_error=True)
-    assert "Getting page https://pypi.gocept.com/initools" in result.stdout
-    result = script.pip(
-        'install', '-vvv', '--index-url', 'https://pypi.org/simple/',
-        'INITools',
+        index-url = {address}/simple2
+        """.format(address=base_address))
     )
-    assert (
-        "Getting page http://download.zope.org/ppix/INITools"
-        not in result.stdout
-    )
-    assert "Getting page https://pypi.gocept.com/INITools" not in result.stdout
-    assert (
-        "Getting page https://pypi.org/simple/initools" in result.stdout
+    script.pip('install', '-vvv', 'INITools', expect_error=True)
+    script.pip(
+        'install', '-vvv', '--index-url', "{}/simple3".format(base_address),
+        'INITools',
     )
 
+    mock_server.stop()
+    requests = mock_server.get_requests()
+    assert len(requests) == 4
+    assert requests[0]["PATH_INFO"] == "/simple1/initools/"
+    assert requests[1]["PATH_INFO"] == "/simple2/initools/"
+    assert requests[2]["PATH_INFO"] == "/simple3/initools/"
+    assert requests[3]["PATH_INFO"] == "/files/INITools-0.2.tar.gz"
+
 
 def test_options_from_venv_config(script, virtualenv):
     """