test: let (most) tests run with no network

nedbat · nedbat · commit 6387d0a60d80 · 2026-01-20T08:48:38.000-05:00
`COVERAGE_PIP_ARGS=--no-build-isolation` lets (most) tests run with no
network
diff --git a/tests/test_venv.py b/tests/test_venv.py
@@ -202,6 +202,10 @@ def coverage_command_fixture(request: pytest.FixtureRequest) -> str:
 
 
 @pytest.mark.xdist_group(name="virtualenv_test")
+@pytest.mark.skipif(
+    bool(os.getenv("COVERAGE_PIP_ARGS")),
+    reason="COVERAGE_PIP_ARGS setting means we shouldn't try pip",
+)
 class VirtualenvTest(CoverageTest):
     """Tests of virtualenv considerations."""
 
diff --git a/tox.ini b/tox.ini
@@ -24,7 +24,7 @@ deps =
 
 # Windows can't update the pip version with pip running, so use Python
 # to install things.
-install_command = python -m pip install -U {opts} {packages}
+install_command = python -m pip install -U {env:COVERAGE_PIP_ARGS} {opts} {packages}
 
 passenv = *
 setenv =
