Address PR feedback: update CONTRIBUTING.md, only set UV_EXCLUDE_NEWER if unset

Author: aclark4life

.evergreen/combine-coverage.sh

@@ -8,7 +8,7 @@ set -eu
 # Set up the virtual env.
 . .evergreen/scripts/setup-dev-env.sh
 export UV_NO_LOCK=1
-export UV_EXCLUDE_NEWER=$(python3 -c "from datetime import datetime, timedelta, timezone; print((datetime.now(timezone.utc) - timedelta(days=7)).strftime('%Y-%m-%dT%H:%M:%SZ'))")
+export UV_EXCLUDE_NEWER="${UV_EXCLUDE_NEWER:-$(python3 -c "from datetime import datetime, timedelta, timezone; print((datetime.now(timezone.utc) - timedelta(days=7)).strftime('%Y-%m-%dT%H:%M:%SZ'))")}"
 uv sync --group coverage
 source .venv/bin/activate
 

.evergreen/scripts/setup_tests.py

@@ -171,8 +171,11 @@ def handle_test_env() -> None:
     write_env("PIP_QUIET")  # Quiet by default.
     write_env("PIP_PREFER_BINARY")  # Prefer binary dists by default.
     write_env("UV_NO_LOCK", "1")
-    exclude_newer = (datetime.now(timezone.utc) - timedelta(days=7)).strftime("%Y-%m-%dT%H:%M:%SZ")
-    write_env("UV_EXCLUDE_NEWER", exclude_newer)
+    if not os.environ.get("UV_EXCLUDE_NEWER"):
+        exclude_newer = (datetime.now(timezone.utc) - timedelta(days=7)).strftime(
+            "%Y-%m-%dT%H:%M:%SZ"
+        )
+        write_env("UV_EXCLUDE_NEWER", exclude_newer)
 
     # Set an environment variable for the test name and sub test name.
     write_env(f"TEST_{test_name.upper()}")

CONTRIBUTING.md

@@ -574,7 +574,5 @@ From the spawn host or Ubuntu image, do the following:
 ## Dependabot updates
 
 Dependabot will raise PRs at most once per week, grouped by GitHub Actions updates and Python requirement
-file updates.  We have a pre-commit hook that will update the `uv.lock` file when requirements change.
-To update the lock file on a failing PR, you can use a method like `gh pr checkout <pr number>`, then run
-`just lint uv-lock` to update the lock file, and then push the changes.  If a typing dependency has changed,
-also run `just typing` and handle any new findings.
+file updates.  To handle a failing Dependabot PR, you can use a method like `gh pr checkout <pr number>`,
+then push the changes.  If a typing dependency has changed, also run `just typing` and handle any new findings.