From 4ed7e53d28b2bae910542ee46864878cb6ebf695 Mon Sep 17 00:00:00 2001
From: Mattia Manzati <mattia.manzati@gmail.com>
Date: Fri, 9 May 2025 09:27:08 +0200
Subject: [PATCH] fallback path for fn when isGeneratorFunction is not
available
---
packages/effect/src/Effect.ts | 6 +++++-
packages/effect/src/Utils.ts | 9 ++++++++-
packages/effect/test/Effect/fn.test.ts | 7 +++++++
3 files changed, 20 insertions(+), 2 deletions(-)
diff --git a/packages/effect/src/Effect.ts b/packages/effect/src/Effect.ts
index 795b5e70194..2dc0caa4fc1 100644
--- a/packages/effect/src/Effect.ts
+++ b/packages/effect/src/Effect.ts
@@ -62,7 +62,7 @@ import type * as Supervisor from "./Supervisor.js"
import type * as Tracer from "./Tracer.js"
import type { Concurrency, Contravariant, Covariant, NoExcessProperties, NoInfer, NotFunction } from "./Types.js"
import type * as Unify from "./Unify.js"
-import { isGeneratorFunction, type YieldWrap } from "./Utils.js"
+import { isGeneratorFunction, isGeneratorIterator, type YieldWrap } from "./Utils.js"
/**
* @since 2.0.0
@@ -14545,6 +14545,10 @@ function fnApply(options: {
} else {
try {
effect = options.body.apply(options.self, options.args)
+ if (isGeneratorIterator(effect)) {
+ const iterator = effect
+ effect = core.fromIterator(() => iterator)
+ }
} catch (error) {
fnError = error
effect = die(error)
diff --git a/packages/effect/src/Utils.ts b/packages/effect/src/Utils.ts
index ef4a0701939..63031b80874 100644
--- a/packages/effect/src/Utils.ts
+++ b/packages/effect/src/Utils.ts
@@ -5,7 +5,7 @@ import { identity } from "./Function.js"
import { globalValue } from "./GlobalValue.js"
import type { Kind, TypeLambda } from "./HKT.js"
import { getBugErrorMessage } from "./internal/errors.js"
-import { isNullable, isObject } from "./Predicate.js"
+import { hasProperty, isFunction, isNullable, isObject } from "./Predicate.js"
import type * as Types from "./Types.js"
/*
@@ -807,3 +807,10 @@ const genConstructor = (function*() {}).constructor
*/
export const isGeneratorFunction = (u: unknown): u is (...args: Array<any>) => Generator<any, any, any> =>
isObject(u) && u.constructor === genConstructor
+
+/**
+ * @since 3.14.21
+ */
+export const isGeneratorIterator = (u: unknown): u is Generator<any, any, any> =>
+ isObject(u) && hasProperty(u, "return") && hasProperty(u, "throw") &&
+ hasProperty(u, Symbol.iterator) && isFunction(u[Symbol.iterator])
diff --git a/packages/effect/test/Effect/fn.test.ts b/packages/effect/test/Effect/fn.test.ts
index a5416625a5a..134541556e5 100644
--- a/packages/effect/test/Effect/fn.test.ts
+++ b/packages/effect/test/Effect/fn.test.ts
@@ -76,6 +76,13 @@ describe("Effect.fn", () => {
strictEqual(fn2.length, 1)
strictEqual(Effect.runSync(fn2(2)), 2)
})
+ it("should work with introduced functions", () => {
+ const f = function*(n: number) {
+ return n
+ }
+ const fn1 = Effect.fn("fn1")((n: number) => f(n))
+ strictEqual(Effect.runSync(fn1(2)), 2)
+ })
})
describe("Effect.fnUntraced", () => {