From 8166bd8941ffb3f8e94ba2e421ae0d8fcb25f974 Mon Sep 17 00:00:00 2001
From: Renegade334 <contact.9a5d6388@renegade334.me.uk>
Date: Tue, 21 Jan 2025 14:10:41 +0000
Subject: [PATCH] feat(collection): use @@species in static methods

---
 packages/collection/src/collection.ts | 11 ++++++++---
 1 file changed, 8 insertions(+), 3 deletions(-)

diff --git a/packages/collection/src/collection.ts b/packages/collection/src/collection.ts
index 288b2291cd19..3f699d844128 100644
--- a/packages/collection/src/collection.ts
+++ b/packages/collection/src/collection.ts
@@ -11,11 +11,11 @@ export type ReadonlyCollection<Key, Value> = Omit<
 
 export interface Collection<Key, Value> {
 	/**
-	 * Ambient declaration to allow `this.constructor[@@species]` in class methods.
+	 * Ambient declaration to allow references to `this.constructor` in class methods.
 	 *
 	 * @internal
 	 */
-	constructor: typeof Collection & { readonly [Symbol.species]: typeof Collection };
+	constructor: typeof Collection;
 }
 
 /**
@@ -1076,7 +1076,7 @@ export class Collection<Key, Value> extends Map<Key, Value> {
 		entries: Iterable<[Key, Value]>,
 		combine: (firstValue: Value, secondValue: Value, key: Key) => Value,
 	): Collection<Key, Value> {
-		const coll = new Collection<Key, Value>();
+		const coll = new this[Symbol.species]<Key, Value>();
 		for (const [key, value] of entries) {
 			if (coll.has(key)) {
 				coll.set(key, combine(coll.get(key)!, value, key));
@@ -1087,6 +1087,11 @@ export class Collection<Key, Value> extends Map<Key, Value> {
 
 		return coll;
 	}
+	
+	/**
+	 * @internal
+	 */
+	declare public static readonly [Symbol.species]: typeof Collection;
 }
 
 /**