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node_modules/@react-aria/utils/src/mergeRefs.ts

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+/*
+ * Copyright 2020 Adobe. All rights reserved.
+ * This file is licensed to you under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License. You may obtain a copy
+ * of the License at http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software distributed under
+ * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
+ * OF ANY KIND, either express or implied. See the License for the specific language
+ * governing permissions and limitations under the License.
+ */
+
+import {MutableRefObject, Ref} from 'react';
+
+/**
+ * Merges multiple refs into one. Works with either callback or object refs.
+ */
+export function mergeRefs<T>(...refs: Array<Ref<T> | MutableRefObject<T> | null | undefined>): Ref<T> {
+  if (refs.length === 1 && refs[0]) {
+    return refs[0];
+  }
+
+  return (value: T | null) => {
+    let hasCleanup = false;
+
+    const cleanups = refs.map(ref => {
+      const cleanup = setRef(ref, value);
+      hasCleanup ||= typeof cleanup == 'function';
+      return cleanup;
+    });
+
+    if (hasCleanup) {
+      return () => {
+        cleanups.forEach((cleanup, i) => {
+          if (typeof cleanup === 'function') {
+            cleanup();
+          } else {
+            setRef(refs[i], null);
+          }
+        });
+      };
+    }
+  };
+}
+
+function setRef<T>(ref: Ref<T> | MutableRefObject<T> | null | undefined, value: T) {
+  if (typeof ref === 'function') {
+    return ref(value);
+  } else if (ref != null) {
+    ref.current = value;
+  }
+}