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oxlint-plugin-effect

provide-named-layer

Intent: Effect.provide receives a named Layer, never an inline composition.

// ❌ no
printMissing.pipe(Effect.provide(Layer.mergeAll(FileRaceList.layer, GoogleSheet.readerLayer)))


// ✅ yes: the Layer is named in the entry point, provided in the dispatch
const missingLayer = Layer.mergeAll(FileRaceList.layer, GoogleSheet.readerLayer)
Missing: () => printMissing.pipe(Effect.provide(missingLayer)),

Trigger: an Effect.provide argument composed inline: Layer.*(…), a ternary, an &&/||, a match/$match.

Exemptions and blind spots: test files, where different fakes per test are idiomatic. Where provide sits (outside the entry point) needs types: see strict-effect-provide (effecttsgo).

Why: an inline Layer cannot be reused and hides which adapters a branch chooses. When branches need different Layers, there is one provide per branch, all in the dispatch: a single Layer with every service would build adapters the command does not use.

Options:

Fix: none