Jesus sucks

backend/frontend/node_modules/@restart/hooks/cjs/useMutationObserver.js

@@ -0,0 +1,78 @@
+"use strict";
+
+exports.__esModule = true;
+exports.default = void 0;
+var _useCustomEffect = _interopRequireDefault(require("./useCustomEffect"));
+var _dequal = require("dequal");
+var _useImmediateUpdateEffect = _interopRequireDefault(require("./useImmediateUpdateEffect"));
+var _useEventCallback = _interopRequireDefault(require("./useEventCallback"));
+var _react = require("react");
+function _interopRequireDefault(obj) { return obj && obj.__esModule ? obj : { default: obj }; }
+function isDepsEqual([nextElement, nextConfig], [prevElement, prevConfig]) {
+  return nextElement === prevElement && (0, _dequal.dequal)(nextConfig, prevConfig);
+}
+
+/**
+ * Observe mutations on a DOM node or tree of DOM nodes.
+ * Depends on the `MutationObserver` api.
+ *
+ * ```tsx
+ * const [element, attachRef] = useCallbackRef(null);
+ *
+ * useMutationObserver(element, { subtree: true }, (records) => {
+ *
+ * });
+ *
+ * return (
+ *   <div ref={attachRef} />
+ * )
+ * ```
+ *
+ * @param element The DOM element to observe
+ * @param config The observer configuration
+ * @param callback A callback fired when a mutation occurs
+ */
+
+/**
+ * Observe mutations on a DOM node or tree of DOM nodes.
+ * use a `MutationObserver` and return records as the are received.
+ *
+ * ```tsx
+ * const [element, attachRef] = useCallbackRef(null);
+ *
+ * const records = useMutationObserver(element, { subtree: true });
+ *
+ * return (
+ *   <div ref={attachRef} />
+ * )
+ * ```
+ *
+ * @param element The DOM element to observe
+ * @param config The observer configuration
+ */
+
+function useMutationObserver(element, config, callback) {
+  const [records, setRecords] = (0, _react.useState)(null);
+  const handler = (0, _useEventCallback.default)(callback || setRecords);
+  (0, _useCustomEffect.default)(() => {
+    if (!element) return;
+
+    // The behavior around reusing mutation observers is confusing
+    // observing again _should_ disable the last listener but doesn't
+    // seem to always be the case, maybe just in JSDOM? In any case the cost
+    // to redeclaring it is gonna be fairly low anyway, so make it simple
+    const observer = new MutationObserver(handler);
+    observer.observe(element, config);
+    return () => {
+      observer.disconnect();
+    };
+  }, [element, config], {
+    isEqual: isDepsEqual,
+    // Intentionally done in render, otherwise observer will miss any
+    // changes made to the DOM during this update
+    effectHook: _useImmediateUpdateEffect.default
+  });
+  return callback ? void 0 : records || [];
+}
+var _default = useMutationObserver;
+exports.default = _default;