Merge pull request #11239 from pradyunsg/fix-coverage-tracking

Fix the coverage tracking nox session

Author: sbidoul

noxfile.py

@@ -229,15 +229,23 @@ def pinned_requirements(path: Path) -> Iterator[Tuple[str, str]]:
 
 @nox.session
 def coverage(session: nox.Session) -> None:
-    if not os.path.exists("./.coverage-output"):
-        os.mkdir("./.coverage-output")
+    # Install source distribution
+    run_with_protected_pip(session, "install", ".")
+
+    # Install test dependencies
+    run_with_protected_pip(session, "install", "-r", REQUIREMENTS["tests"])
+
+    if not os.path.exists(".coverage-output"):
+        os.mkdir(".coverage-output")
     session.run(
         "pytest",
         "--cov=pip",
         "--cov-config=./setup.cfg",
+        *session.posargs,
         env={
             "COVERAGE_OUTPUT_DIR": "./.coverage-output",
-            "COVERAGE_PROCESS_START": "./setup.cfg",
+            "COVERAGE_PROCESS_START": os.fsdecode(Path("setup.cfg").resolve()),
+            "SETUPTOOLS_USE_DISTUTILS": "stdlib",
         },
     )