From b2cc064ac3db65af4fbc7f194c7c4e1a72b26885 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Adrien=20LES=C3=89N=C3=89CHAL?= <lesenechala@laposte.net>
Date: Thu, 19 Dec 2024 22:21:43 +0100
Subject: [PATCH] Fix #52: Remove incorrect type guard of `exists()` from
 `mw.Map`

---
 mw/Map.d.ts                    |  6 +++---
 test-d/regression/52.test-d.ts | 11 +++++++++++
 2 files changed, 14 insertions(+), 3 deletions(-)
 create mode 100644 test-d/regression/52.test-d.ts

diff --git a/mw/Map.d.ts b/mw/Map.d.ts
index f91b62b..2f65789 100644
--- a/mw/Map.d.ts
+++ b/mw/Map.d.ts
@@ -28,8 +28,8 @@ export interface ExtensibleMap<V extends Record<string, any>, TX = unknown>
      * @returns True if the key exists
      * @see https://doc.wikimedia.org/mediawiki-core/master/js/mw.Map.html#.exists
      */
-    exists<S extends keyof V>(selection: S): selection is S;
-    exists<S extends string>(selection: S): selection is S;
+    exists(selection: keyof V): boolean;
+    exists(selection: string): boolean;
 
     /**
      * Get the value of one or more keys.
@@ -95,7 +95,7 @@ declare global {
              * @returns True if the key exists
              * @see https://doc.wikimedia.org/mediawiki-core/master/js/mw.Map.html#.exists
              */
-            exists<S extends keyof V>(selection: S): selection is S;
+            exists(selection: keyof V): boolean;
 
             /**
              * Get the value of one or more keys.
diff --git a/test-d/regression/52.test-d.ts b/test-d/regression/52.test-d.ts
new file mode 100644
index 0000000..d68ef90
--- /dev/null
+++ b/test-d/regression/52.test-d.ts
@@ -0,0 +1,11 @@
+// https://github.com/wikimedia-gadgets/types-mediawiki/issues/52
+import { expectType } from "tsd";
+
+declare const map: mw.Map;
+declare const k: string;
+
+if (map.exists(k)) {
+    expectType<string>(k);
+} else {
+    expectType<string>(k);
+}