What the suite is designed to catch
Citation exports often contain tracking parameters, fragments, parameter-order changes, path-casing differences, and both slash variants. A permissive cleanup function can make reporting look tidy while changing the underlying evidence. These fixtures turn the policy boundary into executable checks.
Recommended implementation contract
- Store the exact observed URL before transformation.
- Attach a version identifier to the normalization policy.
- Return either a comparison key or an explicit error state for every input row.
- Log each applied transformation so a reviewer can reproduce the result.
- Keep redirect and publisher-canonical verification in a separate dated workflow.
- Re-run this suite whenever the allowlist or trailing-slash rule changes.
A production implementation should add organization-specific fixtures for known CMS patterns and should review any proposed parameter removal against real destination behavior. Unknown parameters are retained by default because names such as edition, lang, page, version, and query can select different content.
How to interpret a pass
A passing result means only that the local function matches this published policy for the synthetic case. It does not establish that two pages are equivalent, that a publisher intends one canonical URL, or that the citation is accessible from every location. Redirect chains, authentication walls, challenge pages, timeouts, and regional restrictions require their own timestamped observations.
For reporting, keep counts of raw observations, unique comparison keys, and unique publisher hostnames separate. Label them precisely rather than calling all three “citations.” If a policy change alters historical totals, preserve both versions or rerun the entire frozen dataset under the new version.
example.org hostnames are used to avoid implying that a real publisher appeared in an AI answer.