| name | tsz-conformance |
| description | Triage and maintain TSZ diagnostic conformance. Use when investigating conformance regressions, accepted-regression drift, fingerprint-only failures, issue creation from conformance data, or focused parity fixes that must preserve the conformance gate. |
TSZ Conformance
Conformance is a regression gate. Prefer checked-in artifacts and narrow filters;
CI owns broad runs.
Rules
- Read
AGENTS.md and docs/plan/ROADMAP.md for conformance-affecting work.
- Do not run full conformance locally.
- Treat a failing test as a witness for a structural rule.
- Do not hide regressions with snapshot/allowlist churn.
Offline First
python3 scripts/conformance/query-conformance.py --dashboard
python3 scripts/conformance/query-conformance.py --campaigns
python3 scripts/conformance/query-conformance.py --fingerprint-only
python3 scripts/conformance/query-conformance.py --code TS2322
python3 scripts/conformance/query-conformance.py --code TS2322 --paths-only
Artifacts: conformance-detail.json, conformance-snapshot.json,
conformance-accepted-regressions.txt, conformance-shard-weights.json.
Oracle
Semantics come from the pinned compiler, not from any other copy on the box.
Run manual spot-checks through the wrapper so they match what the gate scores:
scripts/conformance/oracle.sh case.ts --strict --lib es2022 --target es2022
node scripts/node_modules/typescript/lib/tsc.js --version
- Use
oracle.sh, not a bare tsc.js invocation. It runs the pinned
typescript@7.0.2 with the same --singleThreaded --stableTypeOrdering true
flags generate-tsc-cache.rs uses for TypeScript 7+. This is not just about
ordering: typescript@7.0.2 (typescript-go) reports a different diagnostic
set under --singleThreaded. A position-invalid import in a bare { } block
(or if/loop/try body) gets TS2307/TS2305 only single-threaded, not
under the default concurrent scheduler; the same import in a function, class
static { }, or namespace body gets neither, in both modes (#16413).
compare-to-parent.sh/conformance.sh score the single-threaded cache, so a
plain tsc.js case.ts silently disagrees with the gate — hand-oracling
without the flag reads a fix as passing that the gate then fails (this
mis-scoped #16409/#16411).
TypeScript/ (submodule) and any container-global
/opt/**/node_modules/typescript are the 6.0 line. They are corpus and
test cases only — never the source of a semantic rule.- Reading a rule out of 6.0 source and pinning it with tests lands the wrong
behaviour: #16215 encoded
ignoreDeprecations !== "6.0" from a 6.0.2
typescript.js, but 7.0 removed that grace window entirely (#16217).
- 7.0 traps when hand-oracling:
--target es5 was removed — it answers
error TS5108 and emits nothing else, and that line carries no file.ts(l,c):
prefix, so a row filter drops it and every row reads clean. strict also
defaults to true.
Check raw output once before trusting a filtered sweep: an invalid invocation and
a clean compile are indistinguishable after filtering.
Focused Run
./scripts/conformance/conformance.sh run --filter "<name>" --verbose
Keep filters precise. Let harnesses rebuild stale binaries when possible.
Triage
Classify: new/accepted/resolved/fingerprint-only/wrong-code/missing-code/
extra-code/crash/timeout/OOM. Then identify owner: relation, inference,
narrowing, indexed/keyof/mapped/conditional/template, symbol resolution,
diagnostic display, parser recovery, or emit-only.
Before coding, state the structural rule and adjacent cases. Behavior changes
need owning-crate tests.
Accepted-regression drift: verify shard artifacts, update the accepted file
only to match observed failing set, link/file issues for new accepts, and
comment with numbers plus a provenance line.
