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oxlint-plugin-effect

no-provide-on-definition

Intent: a program does not provide its own Layers; its caller does.

// ❌ no
const printMissing = Effect.gen(function* () { … }).pipe(Effect.provide(missingLayer))


// ✅ yes: the program stays unprovided, its caller provides
const printMissing = Effect.gen(function* () { … })
Missing: () => printMissing.pipe(Effect.provide(missingLayer)),

Trigger: Effect.provide applied to Effect.gen(…) or to Effect.fn(…)(…), in all three forms: with .pipe, as an Effect.fn pipeable, data-first.

Exemptions and blind spots: test files. A program passed directly to Effect.run*, also through .pipe(…) or data-first Effect.* combinators (Effect.runPromise(Effect.gen(…).pipe(Effect.provide(layer), Effect.result))): it is already being dispatched; through any other function it is still reported. A context captured in an enclosing generator with const ctx = yield* Effect.context<R>() (also followed by .pipe(…)) and handed back to a method of the Layer being built: the caller chose the adapters when it built the Layer. A context obtained through a helper (yield* contextWithoutSpan()) is still reported. provide on a named program is allowed; strict-effect-provide (effecttsgo) reports it too.

Why: a program that provides its own Layers can no longer be wired to different adapters by its caller.

Options:

Fix: none