[schmitch]

Stacked on #890: merge that first; this one is then retargeted to main (do not merge it into #890's branch).

What changed

Three checks catch what rustc, clippy and tsc let through. #890 removed this kind of code by hand; these checks fail CI when more appears.

cargo xtask unused (new xtask/src/unused.rs, run by the fmt job)

• Reads every workspace member's Cargo.toml and .rs files as text. xtask stays dependency-free.
• Fails on:
  • a pub item (fn, struct, enum, union, trait, type, const, static) whose name appears nowhere else in the workspace's sources. Definitions inside comments, doc tests and string literals are ignored.
  • a dependency its crate's sources never name (name::…, use name, extern crate name), with - read as _ or dropped (md-5 is md5).
  • a dev-dependency that repeats one of the crate's dependencies with the same or fewer features.
  • a [workspace.dependencies] entry no member inherits.
• It errs towards silence. Any other mention of a name, including in a comment or a string, counts as a use.
• A dependency the code needs without naming it (one that only enables a feature of another) can be kept under [package.metadata.unused] ignore = [...] in its crate's manifest. Nothing needs that today.
• On main before Remove unused code and dependencies #890, it reports exactly the 44 items Remove unused code and dependencies #890 removes (14 pub items, 5 dependencies, 25 dev-dependencies) and nothing else. On Remove unused code and dependencies #890's branch it passes.

pnpm run knip (web job, config in web/knip.jsonc)

• Fails on a file, an export or a package.json package that nothing imports.
• Settings:
  • src/routes.ts is an entry, because the router plugin loads it by path.
  • The stylesheets are part of the project, so @import 'tailwindcss' counts as a use and the config needs no ignore list.
  • ignoreExportsUsedInFile is on, so an export that only its own module uses is left alone.
• knip is pinned at 6.43.0, the newest release outside pnpm's 7-day minimumReleaseAge (6.44.1 is three days old). The lockfile adds knip and its dependencies; every existing package keeps its version, and Vite's entry only gains yaml as a resolved peer.
• On main before Remove unused code and dependencies #890, it reports the 4 unused files, the 2 devtools packages and the 16 unused exports and types that Remove unused code and dependencies #890 removes. On Remove unused code and dependencies #890's branch it passes.

cargo xtask doc-check (clippy job, last step)

• Runs cargo doc --workspace --all-features --no-deps --document-private-items with RUSTDOCFLAGS="-D warnings -A rustdoc::private_intra_doc_links".
• A doc link to a renamed or removed item now fails CI, as does an ambiguous link.
• Links from public to private items are allowed, because private items are documented too.
• --all-features brings in forge-e2e, which is entirely behind its feature.
• It found 23 problems, all fixed in this PR:
  • 17 broken links. Most only needed a path. Three named things that no longer exist: super::OidcProvider (the server builds the ClaimMapping in OidcRuntime::build), the free function authz::can_read (now Authz::can_read), and MockOidc::set_next_id_token_with_retired_key. The doc of MockOidc::rotate_key also described keeping the old signer, which the code doesn't do; it is rewritten to match the code.
  • 4 ambiguous links (format, evaluate, reference), now disambiguated.
  • 2 links with a redundant explicit target.
• Locally it takes about a minute once the dependencies are built. In CI it runs after cargo sqlx prepare --check, which has already check-built every dependency with every feature.

DEVELOPMENT.md gets a section, "Unused code and stale doc links", covering all three and how to keep a dependency. The new commands are added to cargo xtask help and to the helper-command list.

Tests

Run locally on this branch:

• cargo test -p xtask: 45 + 2 pass, including 9 new tests for the manifest reader, the source scan and each kind of finding.
• cargo xtask unused, cargo xtask doc-check, cargo xtask docs --check and cargo xtask changelog --check.
• cargo fmt --all --check, and cargo clippy -p xtask --all-targets -- -D warnings.
• cd web && pnpm install --frozen-lockfile && pnpm run knip.

CI does not run on a stacked pull request. It will run once this PR is retargeted to main and pushed again, or by hand with gh workflow run ci.yml --ref claude/unused-code-checks -f base=main.

Changelog

No fragment. Nothing changes for the people who run Forge.

Notes

• I chose an xtask check over cargo-shear / cargo-machete to keep the repository's checks self-contained and runnable without installing anything. If you would rather use cargo-shear, taiki-e/install-action (already pinned in CI) can install it, and the xtask check could then shrink to the pub-item and repeated dev-dependency parts.
• None of these checks know whether a comment's prose is still true. The audit behind Remove unused code and dependencies #890 also found stale docs, config examples and duplicated helpers; those still need pull requests of their own.

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Generated by Claude Code