rect: Fix issues with the observer between renders

packages/alert/src/index.tsx

@@ -61,7 +61,7 @@ let renderTimer: number | null;
  * @see Docs https://reacttraining.com/reach-ui/alert
  */
 export const Alert = forwardRef<HTMLDivElement, AlertProps>(function Alert(
-  { children, type = "polite", ...props },
+  { children, type: regionType = "polite", ...props },
   forwardedRef
 ) {
   const ownRef = useRef(null);
@@ -75,7 +75,7 @@ export const Alert = forwardRef<HTMLDivElement, AlertProps>(function Alert(
     // eslint-disable-next-line react-hooks/exhaustive-deps
     [children, props]
   );
-  useMirrorEffects(type, child, ownRef);
+  useMirrorEffects(regionType, child, ownRef);
 
   return child;
 });
@@ -141,8 +141,8 @@ function renderAlerts() {
   }
   renderTimer = window.setTimeout(() => {
     Object.keys(elements).forEach((elementType) => {
-      let type: RegionTypes = elementType as RegionTypes;
-      let container = liveRegions[type]!;
+      let regionType: RegionTypes = elementType as RegionTypes;
+      let container = liveRegions[regionType]!;
       if (container) {
         render(
           <VisuallyHidden>
@@ -154,47 +154,46 @@ function renderAlerts() {
               // will send out an accessible status event to assistive
               // technology products which can then notify the user about it.
               // https://developer.mozilla.org/en-US/docs/Web/Accessibility/ARIA/ARIA_Techniques/Using_the_status_role
-              role={type === "assertive" ? "alert" : "status"}
-              aria-live={type}
+              role={regionType === "assertive" ? "alert" : "status"}
+              aria-live={regionType}
             >
-              {Object.keys(elements[type]).map((key) =>
-                React.cloneElement(elements[type][key], {
+              {Object.keys(elements[regionType]).map((key) =>
+                React.cloneElement(elements[regionType][key], {
                   key,
                   ref: null,
                 })
               )}
             </div>
           </VisuallyHidden>,
-          liveRegions[type]
+          liveRegions[regionType]
         );
       }
     });
   }, 500);
 }
 
 function useMirrorEffects(
-  type: RegionTypes,
+  regionType: RegionTypes,
   element: JSX.Element,
   ref: React.RefObject<any>
 ) {
-  const prevType = usePrevious<RegionTypes>(type);
+  const prevType = usePrevious<RegionTypes>(regionType);
   const mirror = useRef<Mirror | null>(null);
   const mounted = useRef(false);
   useEffect(() => {
     const ownerDocument = getOwnerDocument(ref.current) || document;
     if (!mounted.current) {
       mounted.current = true;
-      mirror.current = createMirror(type, ownerDocument);
+      mirror.current = createMirror(regionType, ownerDocument);
       mirror.current.mount(element);
-    } else if (prevType !== type) {
+    } else if (prevType !== regionType) {
       mirror.current && mirror.current.unmount();
-      mirror.current = createMirror(type, ownerDocument);
+      mirror.current = createMirror(regionType, ownerDocument);
       mirror.current.mount(element);
     } else {
       mirror.current && mirror.current.update(element);
     }
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [element, type, prevType]);
+  }, [element, regionType, prevType, ref]);
 
   useEffect(() => {
     return () => {

packages/rect/examples/change-observed-ref.example.tsx

@@ -0,0 +1,29 @@
+import React from "react";
+import { useRect } from "@reach/rect";
+
+let name = "Change the observed ref";
+
+function Example() {
+  const refLeft = React.useRef<HTMLTextAreaElement>(null);
+  const refRight = React.useRef<HTMLTextAreaElement>(null);
+  const [whichRect, setWhichRect] = React.useState(true);
+  const rect = useRect(whichRect ? refLeft : refRight);
+  return (
+    <div>
+      <pre>
+        {whichRect ? "left" : "right"}: {JSON.stringify(rect, null, 2)}
+      </pre>
+      <button onClick={() => setWhichRect(!whichRect)}>
+        Toggle Observed Ref
+      </button>
+      <div>
+        <textarea ref={refLeft} defaultValue="resize this" />
+        <textarea ref={refRight} defaultValue="resize this" />
+      </div>
+    </div>
+  );
+}
+
+Example.story = { name };
+export const Comp = Example;
+export default { title: "Rect" };

packages/rect/package.json

@@ -13,7 +13,7 @@
     "build": "ts-node ../../scripts/build"
   },
   "dependencies": {
-    "@reach/observe-rect": "1.1.0",
+    "@reach/observe-rect": "1.2.0",
     "@reach/utils": "0.10.4",
     "prop-types": "^15.7.2",
     "tslib": "^2.0.0"

packages/rect/src/index.tsx

@@ -65,7 +65,10 @@ export type RectProps = {
    *
    * @see Docs https://reacttraining.com/reach-ui/rect#rect-onchange
    */
-  children(args: { rect: PRect | null; ref: React.Ref<any> }): JSX.Element;
+  children(args: {
+    rect: PRect | null;
+    ref: React.RefObject<any>;
+  }): JSX.Element;
 };
 
 if (__DEV__) {
@@ -86,48 +89,58 @@ if (__DEV__) {
  * @param observe
  * @param onChange
  */
-export function useRect<T extends HTMLElement = HTMLElement>(
-  nodeRef: React.RefObject<T>,
+export function useRect<T extends Element = HTMLElement>(
+  nodeRef: React.RefObject<T | undefined | null>,
   observe: boolean = true,
   onChange?: (rect: DOMRect) => void
 ): null | DOMRect {
+  let [element, setElement] = useState(nodeRef.current);
   let initialRectSet = useRef(false);
   let [rect, setRect] = useState<DOMRect | null>(null);
-  let observerRef = useRef<any>(null);
+  let onChangeRef = useRef<typeof onChange>();
+
   useIsomorphicLayoutEffect(() => {
-    const cleanup = () => {
-      observerRef.current && observerRef.current.unobserve();
-    };
+    onChangeRef.current = onChange;
+  });
 
-    if (!nodeRef.current) {
-      console.warn("You need to place the ref");
-      return cleanup;
+  useIsomorphicLayoutEffect(() => {
+    if (nodeRef.current !== element) {
+      setElement(nodeRef.current);
     }
+  });
 
-    if (!observerRef.current) {
-      observerRef.current = observeRect(nodeRef.current, (rect: DOMRect) => {
-        onChange && onChange(rect);
-        setRect(rect);
-      });
+  useIsomorphicLayoutEffect(() => {
+    if (element && !initialRectSet.current) {
+      initialRectSet.current = true;
+      setRect(element.getBoundingClientRect());
     }
+  }, [element]);
 
-    if (!initialRectSet.current) {
-      initialRectSet.current = true;
-      setRect(nodeRef.current.getBoundingClientRect());
+  useIsomorphicLayoutEffect(() => {
+    let observer: ReturnType<typeof observeRect>;
+    if (!element) {
+      console.warn("You need to place the ref");
+      return cleanup;
     }
 
-    observe && observerRef.current.observe();
+    observer = observeRect(element, (rect) => {
+      onChangeRef.current && onChangeRef.current(rect);
+      setRect(rect);
+    });
+
+    observe && observer.observe();
     return cleanup;
-    // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, [observe, onChange]);
+
+    function cleanup() {
+      observer && observer.unobserve();
+    }
+  }, [observe, element]);
 
   return rect;
 }
 
 export default Rect;
 
-export type PartialRect = Partial<PRect>;
-
 export type PRect = Partial<DOMRect> & {
   readonly bottom: number;
   readonly height: number;

packages/utils/src/index.tsx

@@ -157,10 +157,10 @@ export function boolOrBoolString(value: any): value is "true" | true {
 }
 
 export function canUseDOM() {
-  return (
+  return !!(
     typeof window !== "undefined" &&
-    typeof window.document !== "undefined" &&
-    typeof window.document.createElement !== "undefined"
+    window.document &&
+    window.document.createElement
   );
 }
 
@@ -615,7 +615,7 @@ export function useForkedRef<RefValueType = any>(
       });
     };
     // eslint-disable-next-line react-hooks/exhaustive-deps
-  }, refs);
+  }, [...refs]);
 }
 
 /**

yarn.lock

@@ -3112,10 +3112,10 @@
   dependencies:
     "@types/node" ">= 8"
 
-"@reach/observe-rect@1.1.0":
-  version "1.1.0"
-  resolved "https://registry.yarnpkg.com/@reach/observe-rect/-/observe-rect-1.1.0.tgz#4e967a93852b6004c3895d9ed8d4e5b41895afde"
-  integrity sha512-kE+jvoj/OyJV24C03VvLt5zclb9ArJi04wWXMMFwQvdZjdHoBlN4g0ZQFjyy/ejPF1Z/dpUD5dhRdBiUmIGZTA==
+"@reach/observe-rect@1.2.0":
+  version "1.2.0"
+  resolved "https://registry.yarnpkg.com/@reach/observe-rect/-/observe-rect-1.2.0.tgz#d7a6013b8aafcc64c778a0ccb83355a11204d3b2"
+  integrity sha512-Ba7HmkFgfQxZqqaeIWWkNK0rEhpxVQHIoVyW1YDSkGsGIXzcaW4deC8B0pZrNSSyLTdIk7y+5olKt5+g0GmFIQ==
 
 "@reach/router@^1.2.1", "@reach/router@^1.3.3":
   version "1.3.3"