Update mergeRefs util for React 19 (#11108)

eslint-suppressions.json

@@ -984,11 +984,6 @@
       "count": 1
     }
   },
-  "src/lib/merge-refs.ts": {
-    "@typescript-eslint/no-explicit-any": {
-      "count": 1
-    }
-  },
   "src/lib/notifications/notifications.ts": {
     "@typescript-eslint/no-floating-promises": {
       "count": 5

src/lib/merge-refs.ts

@@ -1,3 +1,22 @@
+import {type Ref, type RefCallback} from 'react'
+
+/**
+ * Assigns a value to a ref.
+ * @param ref The ref to assign the value to.
+ * @param value The value to assign to the ref.
+ * @returns The ref cleanup callback, if any.
+ */
+function assignRef<T>(
+  ref: Ref<T> | undefined | null,
+  value: T | null,
+): ReturnType<RefCallback<T>> {
+  if (typeof ref === 'function') {
+    return ref(value)
+  } else if (ref) {
+    ref.current = value
+  }
+}
+
 /**
  * This TypeScript function merges multiple React refs into a single ref callback.
  * When developing low level UI components, it is common to have to use a local ref
@@ -12,16 +31,18 @@
  * @returns The function `mergeRefs` is being returned. It takes an array of mutable or legacy refs and
  * returns a ref callback function that can be used to merge multiple refs into a single ref.
  */
-export function mergeRefs<T = any>(
-  refs: Array<React.MutableRefObject<T> | React.Ref<T> | undefined>,
-): React.RefCallback<T> {
-  return value => {
-    refs.forEach(ref => {
-      if (typeof ref === 'function') {
-        ref(value)
-      } else if (ref != null) {
-        ;(ref as React.MutableRefObject<T | null>).current = value
-      }
-    })
+export function mergeRefs<T>(refs: (Ref<T> | undefined)[]): Ref<T> {
+  return (value: T | null) => {
+    const cleanups: (() => void)[] = []
+
+    for (const ref of refs) {
+      const cleanup = assignRef(ref, value)
+      const isCleanup = typeof cleanup === 'function'
+      cleanups.push(isCleanup ? cleanup : () => assignRef(ref, null))
+    }
+
+    return () => {
+      for (const cleanup of cleanups) cleanup()
+    }
   }
 }