From 12f387164b667a3181b333f147c0175801a5d464 Mon Sep 17 00:00:00 2001
From: rijenkii <me@rijenkii.tk>
Date: Mon, 7 Apr 2025 18:15:27 +0700
Subject: [PATCH 1/2] Fix `map` and `mapErr` types

---
 src/result-async.ts | 12 ++++++------
 1 file changed, 6 insertions(+), 6 deletions(-)

diff --git a/src/result-async.ts b/src/result-async.ts
index 20120d2b..1f7d1438 100644
--- a/src/result-async.ts
+++ b/src/result-async.ts
@@ -86,14 +86,14 @@ export class ResultAsync<T, E> implements PromiseLike<Result<T, E>> {
     ) as CombineResultsWithAllErrorsArrayAsync<T>
   }
 
-  map<A>(f: (t: T) => A | Promise<A>): ResultAsync<A, E> {
+  map<A>(f: (t: T) => A): ResultAsync<Awaited<A>, E> {
     return new ResultAsync(
       this._promise.then(async (res: Result<T, E>) => {
         if (res.isErr()) {
-          return new Err<A, E>(res.error)
+          return new Err<Awaited<A>, E>(res.error)
         }
 
-        return new Ok<A, E>(await f(res.value))
+        return new Ok<Awaited<A>, E>(await f(res.value))
       }),
     )
   }
@@ -146,14 +146,14 @@ export class ResultAsync<T, E> implements PromiseLike<Result<T, E>> {
     )
   }
 
-  mapErr<U>(f: (e: E) => U | Promise<U>): ResultAsync<T, U> {
+  mapErr<U>(f: (e: E) => U): ResultAsync<T, Awaited<U>> {
     return new ResultAsync(
       this._promise.then(async (res: Result<T, E>) => {
         if (res.isOk()) {
-          return new Ok<T, U>(res.value)
+          return new Ok<T, Awaited<U>>(res.value)
         }
 
-        return new Err<T, U>(await f(res.error))
+        return new Err<T, Awaited<U>>(await f(res.error))
       }),
     )
   }

From 369b00c8e790f48810cbde07b253777bcbf15296 Mon Sep 17 00:00:00 2001
From: rijenkii <me@rijenkii.tk>
Date: Mon, 7 Apr 2025 18:30:54 +0700
Subject: [PATCH 2/2] Create changeset

---
 .changeset/violet-onions-film.md | 5 +++++
 1 file changed, 5 insertions(+)
 create mode 100644 .changeset/violet-onions-film.md

diff --git a/.changeset/violet-onions-film.md b/.changeset/violet-onions-film.md
new file mode 100644
index 00000000..9e1503ac
--- /dev/null
+++ b/.changeset/violet-onions-film.md
@@ -0,0 +1,5 @@
+---
+"neverthrow": patch
+---
+
+Fix `map` and `mapErr` types