test:ci now runs c8 with --all --include "src/**/*.ts" --100, so the
build job fails when any runtime file under src/ is untested. --all is
what makes the gate non-vacuous: without it c8 counts only the files the
suite happened to load, and a new untested module stays invisible.
Add src/index.test.ts to load the public barrel, which was previously
never imported at runtime and so read as 0% under --all. matcher-shared.ts
is types-only (an empty runtime image) and carries a file-level c8 ignore
with the reason.
Why 100% and the rejected alternatives: development/ci.md § Coverage
threshold.
`UnsupportedReason` tested `IsLiteral<PatternKey<T>> extends false`.
`IsLiteral` is `boolean` for a union that mixes a literal with a broad
type (`"a" | \`x-${number}\``), so `boolean extends false` is false and
the mix was accepted. Test `extends true` instead, which rejects it.
Found while adding property-union broad-universe coverage; the gate is
shared with the primitive-union matcher.
An open universe (`string`, `number`, a template literal) makes the
handler map index-like, so a partial object satisfied the exhaustive
overload and the runtime `dispatch` throw was reachable. A universe
containing a member and its stringification (`"true" | true`, `1 | "1"`)
collapsed two members onto one key.
- reject broad universes and value/stringification collisions at the
factory, with a diagnostic naming the reason
- invert `PatternKey` against the universe (`Member<T, K>`) instead of
`PatternParam<K>`, so a standalone `"true"` is typed `"true"`
- intersect `UniverseGate<T>` into the handler and fallback parameters,
preserving `R` inference and the popup
A `boolean` / `null` / `undefined` discriminant cannot key a handler
map, so the tagged-union matcher now routes it through the
`PatternKey` / `PatternParam` projection the primitive-union matcher
already used. Both matchers share the projection from
`matcher-shared.ts`; `MapTaggedUnion`, `Handlers`, `HandledMembers`
and `MustBePartial` key off the projected form and invert it to
recover the real member.
Covers exhaustive and fallback dispatch, the redundant-fallback
guard, and the LSP popup offering the tags by name.
`getMatcher` / `getMatcherW` become `getPrimitiveUnionMatcher` /
`getPrimitiveUnionMatcherW`; `src/primitive.ts` and its test move to
`src/primitive-union.*`. The `Union` suffix mirrors `getTaggedUnionMatcher`.
tmu