Test network.lazy_wheel.dist_from_wheel_url

tests/lib/requests_mocks.py

@@ -28,7 +28,7 @@ def __init__(self, contents):
         self.status_code = 200
         self.connection = None
         self.url = None
-        self.headers = {}
+        self.headers = {'Content-Length': len(contents)}
         self.history = []
 
     def raise_for_status(self):

tests/unit/test_network_lazy_wheel.py

@@ -0,0 +1,50 @@
+from zipfile import BadZipfile
+
+from pip._vendor.pkg_resources import Requirement
+from pytest import fixture, mark, raises
+
+from pip._internal.network.lazy_wheel import dist_from_wheel_url
+from pip._internal.network.session import PipSession
+from tests.lib.requests_mocks import MockResponse
+
+MYPY_0_782_WHL = (
+    'https://files.pythonhosted.org/packages/9d/65/'
+    'b96e844150ce18b9892b155b780248955ded13a2581d31872e7daa90a503/'
+    'mypy-0.782-py3-none-any.whl'
+)
+MYPY_0_782_REQS = {
+    Requirement('typed-ast (<1.5.0,>=1.4.0)'),
+    Requirement('typing-extensions (>=3.7.4)'),
+    Requirement('mypy-extensions (<0.5.0,>=0.4.3)'),
+    Requirement('psutil (>=4.0); extra == "dmypy"'),
+}
+
+
+@fixture
+def session():
+    return PipSession()
+
+
+@mark.network
+def test_dist_from_wheel_url(session):
+    """Test if the acquired distribution contain correct information."""
+    dist = dist_from_wheel_url('mypy', MYPY_0_782_WHL, session)
+    assert dist.key == 'mypy'
+    assert dist.version == '0.782'
+    assert dist.extras == ['dmypy']
+    assert set(dist.requires(dist.extras)) == MYPY_0_782_REQS
+
+
+@mark.network
+def test_dist_from_wheel_url_no_range(session, monkeypatch):
+    """Test handling when HTTP range requests are not supported."""
+    monkeypatch.setattr(session, 'head', lambda *a, **kw: MockResponse(b''))
+    with raises(RuntimeError):
+        dist_from_wheel_url('mypy', MYPY_0_782_WHL, session)
+
+
+@mark.network
+def test_dist_from_wheel_url_not_zip(session):
+    """Test handling with the given URL does not point to a ZIP."""
+    with raises(BadZipfile):
+        dist_from_wheel_url('python', 'https://www.python.org/', session)