feat: add typings for hooks

src/hooks/tests/useIndexOfLastVisibleChild.test.jsx → src/hooks/tests/useIndexOfLastVisibleChild.test.tsx

@@ -12,8 +12,8 @@ window.ResizeObserver = window.ResizeObserver
   }));
 
 function TestComponent() {
-  const [containerElementRef, setContainerElementRef] = React.useState(null);
-  const overflowElementRef = React.useRef(null);
+  const [containerElementRef, setContainerElementRef] = React.useState<HTMLDivElement | null>(null);
+  const overflowElementRef = React.useRef<HTMLDivElement>(null);
   const indexOfLastVisibleChild = useIndexOfLastVisibleChild(containerElementRef, overflowElementRef.current);
 
   return (

src/hooks/tests/useToggle.test.jsx → src/hooks/tests/useToggle.test.tsx

@@ -4,6 +4,7 @@ import { render, screen } from '@testing-library/react';
 import userEvent from '@testing-library/user-event';
 
 import { useToggle } from '../..';
+import { ToggleHandlers } from '../useToggle';
 
 const TOGGLE_IS_ON = 'on';
 const TOGGLE_IS_OFF = 'off';
@@ -19,7 +20,7 @@ const resetHandlerMocks = () => {
 };
 
 // eslint-disable-next-line react/prop-types
-function FakeComponent({ defaultIsOn, handlers }) {
+function FakeComponent({ defaultIsOn, handlers }: { defaultIsOn: boolean, handlers: ToggleHandlers }) {
   const [isOn, setOn, setOff, toggle] = useToggle(defaultIsOn, handlers);
 
   return (

src/hooks/useArrowKeyNavigation.jsx → src/hooks/useArrowKeyNavigation.tsx

@@ -1,16 +1,24 @@
 import { useRef, useEffect } from 'react';
 
-/**
- * A React hook to enable arrow key navigation on a component.
- */
+interface HandleEnterArgs {
+  event: KeyboardEvent;
+  currentIndex: number;
+  activeElement: HTMLElement;
+}
 
-function handleEnter({ event, currentIndex, activeElement }) {
+function handleEnter({ event, currentIndex, activeElement }: HandleEnterArgs) {
   if (currentIndex === -1) { return; }
   activeElement.click();
   event.preventDefault();
 }
 
-function handleArrowKey({ event, currentIndex, availableElements }) {
+interface HandleArrowKeyArgs {
+  event: KeyboardEvent;
+  currentIndex: number;
+  availableElements: NodeListOf<HTMLElement>;
+}
+
+function handleArrowKey({ event, currentIndex, availableElements }: HandleArrowKeyArgs) {
   // If the focus isn't in the container, focus on the first thing
   if (currentIndex === -1) { availableElements[0].focus(); }
 
@@ -36,6 +44,13 @@
   event.preventDefault();
 }
 
+interface HandleEventsArgs {
+  event: KeyboardEvent;
+  ignoredKeys?: string[];
+  parentNode: HTMLElement | undefined;
+  selectors?: string;
+}
+
 /**
  * Implement arrow key navigation for the given parentNode
  */
@@ -44,7 +59,7 @@
   ignoredKeys = [],
   parentNode,
   selectors = 'a,button,input',
-}) {
+}: HandleEventsArgs) {
   if (!parentNode) { return; }
 
   const { key } = event;
@@ -60,7 +75,7 @@
   if (!parentNode.contains(activeElement)) { return; }
 
   // Get the list of elements we're allowed to scroll through
-  const availableElements = parentNode.querySelectorAll(selectors);
+  const availableElements = parentNode.querySelectorAll<HTMLElement>(selectors);
 
   // No elements are available to loop through.
   if (!availableElements.length) { return; }
@@ -70,18 +85,27 @@
     (availableElement) => availableElement === activeElement,
   );
 
-  if (key === 'Enter') {
-    handleEnter({ event, currentIndex, activeElement });
+  if (key === 'Enter' && activeElement) {
+    handleEnter({ event, currentIndex, activeElement: activeElement as HTMLElement });
   }
   handleArrowKey({ event, currentIndex, availableElements });
 }
 
-export default function useArrowKeyNavigation(props) {
-  const { selectors, ignoredKeys } = props || {};
-  const parentNode = useRef();
+export interface ArrowKeyNavProps {
+  /** e.g. 'a,button,input' */
+  selectors?: string;
+  ignoredKeys?: string[];
+}
+
+/**
+ * A React hook to enable arrow key navigation on a component.
+ */
+export default function useArrowKeyNavigation(props: ArrowKeyNavProps = {}) {
+  const { selectors, ignoredKeys } = props;
+  const parentNode = useRef<HTMLElement>();
 
   useEffect(() => {
-    const eventHandler = (event) => {
+    const eventHandler = (event: KeyboardEvent) => {
       handleEvents({
         event, ignoredKeys, parentNode: parentNode.current, selectors,
       });

src/hooks/useIndexOfLastVisibleChild.jsx → src/hooks/useIndexOfLastVisibleChild.tsx

@@ -5,25 +5,32 @@ import { useLayoutEffect, useState } from 'react';
  * that fits within its bounding rectangle. This is done by summing the widths
  * of the children until they exceed the width of the container.
  *
- * @param {Element} containerElementRef - container element
- * @param {Element} overflowElementRef - overflow element
- *
  * The hook returns the index of the last visible child.
+ *
+ * @param containerElementRef - container element
+ * @param overflowElementRef - overflow element
  */
-const useIndexOfLastVisibleChild = (containerElementRef, overflowElementRef) => {
+const useIndexOfLastVisibleChild = (
+  containerElementRef: HTMLElement | null,
+  overflowElementRef: HTMLElement | null,
+): number => {
   const [indexOfLastVisibleChild, setIndexOfLastVisibleChild] = useState(-1);
 
   useLayoutEffect(() => {
+    if (!containerElementRef) {
+      return undefined;
+    }
+
     function updateLastVisibleChildIndex() {
       // Get array of child nodes from NodeList form
-      const childNodesArr = Array.prototype.slice.call(containerElementRef.children);
+      const childNodesArr = Array.prototype.slice.call(containerElementRef!.children);
       const { nextIndexOfLastVisibleChild } = childNodesArr
         // filter out the overflow element
         .filter(childNode => childNode !== overflowElementRef)
         // sum the widths to find the last visible element's index
         .reduce((acc, childNode, index) => {
           acc.sumWidth += childNode.getBoundingClientRect().width;
-          if (acc.sumWidth <= containerElementRef.getBoundingClientRect().width) {
+          if (acc.sumWidth <= containerElementRef!.getBoundingClientRect().width) {
             acc.nextIndexOfLastVisibleChild = index;
           }
           return acc;
@@ -32,23 +39,18 @@ const useIndexOfLastVisibleChild = (containerElementRef, overflowElementRef) =>
           // sometimes we'll show a dropdown with one item in it when it would fit,
           // but allowing this case dramatically simplifies the calculations we need
           // to do above.
-          sumWidth: overflowElementRef ? overflowElementRef.getBoundingClientRect().width : 0,
+          sumWidth: overflowElementRef?.getBoundingClientRect().width ?? 0,
           nextIndexOfLastVisibleChild: -1,
         });
 
       setIndexOfLastVisibleChild(nextIndexOfLastVisibleChild);
     }
 
-    if (containerElementRef) {
-      updateLastVisibleChildIndex();
-
-      const resizeObserver = new ResizeObserver(() => updateLastVisibleChildIndex());
-      resizeObserver.observe(containerElementRef);
-
-      return () => resizeObserver.disconnect();
-    }
+    updateLastVisibleChildIndex();
 
-    return undefined;
+    const resizeObserver = new ResizeObserver(() => updateLastVisibleChildIndex());
+    resizeObserver.observe(containerElementRef);
+    return () => resizeObserver.disconnect();
   }, [containerElementRef, overflowElementRef]);
 
   return indexOfLastVisibleChild;

src/hooks/useIsVisible.jsx → src/hooks/useIsVisible.tsx

@@ -1,7 +1,10 @@
-import { useRef, useState, useEffect } from 'react';
+import React, { useRef, useState, useEffect } from 'react';
 
-const useIsVisible = (defaultIsVisible = true) => {
-  const sentinelRef = useRef();
+const useIsVisible = (defaultIsVisible = true): [
+  isVisible: boolean,
+  sentinelRef: React.MutableRefObject<HTMLElement | null>,
+] => {
+  const sentinelRef = useRef<HTMLElement | null>(null);
   const [isVisible, setIsVisible] = useState(defaultIsVisible);
 
   useEffect(() => {

src/hooks/useToggle.tsx

@@ -0,0 +1,38 @@
+import { useState, useCallback } from 'react';
+
+export type Toggler = [
+  isOn: boolean,
+  setOn: () => void,
+  setOff: () => void,
+  toggle: () => void,
+];
+
+export interface ToggleHandlers {
+  handleToggleOn?: () => void;
+  handleToggleOff?: () => void;
+  handleToggle?: (newStatus: boolean) => void;
+}
+
+export default function useToggle(defaultIsOn = false, handlers: ToggleHandlers = {}): Toggler {
+  const { handleToggleOn, handleToggleOff, handleToggle } = handlers;
+  const [isOn, setIsOn] = useState(defaultIsOn);
+
+  const setOn = useCallback(() => {
+    setIsOn(true);
+    handleToggleOn?.();
+    handleToggle?.(true);
+  }, [handleToggleOn, handleToggle]);
+
+  const setOff = useCallback(() => {
+    setIsOn(false);
+    handleToggleOff?.();
+    handleToggle?.(false);
+  }, [handleToggleOff, handleToggle]);
+
+  const toggle = useCallback(() => {
+    const doToggle = isOn ? setOff : setOn;
+    doToggle();
+  }, [isOn, setOn, setOff]);
+
+  return [isOn, setOn, setOff, toggle];
+}

src/hooks/useWindowSize.jsx → src/hooks/useWindowSize.tsx

@@ -1,9 +1,14 @@
 import { useState, useLayoutEffect } from 'react';
 
-function useWindowSize() {
+export interface WindowSizeData {
+  width: number | undefined;
+  height: number | undefined;
+}
+
+function useWindowSize(): WindowSizeData {
   // Initialize state with undefined width/height so server and client renders match
   // Learn more here: https://joshwcomeau.com/react/the-perils-of-rehydration/
-  const [windowSize, setWindowSize] = useState({
+  const [windowSize, setWindowSize] = useState<WindowSizeData>({
     width: undefined,
     height: undefined,
   });

src/index.d.ts

@@ -40,6 +40,11 @@ export { default as ModalLayer } from './Modal/ModalLayer';
 export { default as Overlay, OverlayTrigger } from './Overlay';
 export { default as Portal } from './Modal/Portal';
 export { default as Tooltip } from './Tooltip';
+export { default as useWindowSize, type WindowSizeData } from './hooks/useWindowSize';
+export { default as useToggle, type Toggler, type ToggleHandlers } from './hooks/useToggle';
+export { default as useArrowKeyNavigation, type ArrowKeyNavProps } from './hooks/useArrowKeyNavigation';
+export { default as useIndexOfLastVisibleChild } from './hooks/useIndexOfLastVisibleChild';
+export { default as useIsVisible } from './hooks/useIsVisible';
 
 // // // // // // // // // // // // // // // // // // // // // // // // // // //
 // Things that don't have types
@@ -187,11 +192,6 @@ export const Sticky: any; // from './Sticky';
 export const SelectableBox: any; // from './SelectableBox';
 export const breakpoints: any; // from './utils/breakpoints';
 export const Variant: any; // from './utils/constants';
-export const useWindowSize: any; // from './hooks/useWindowSize';
-export const useToggle: any; // from './hooks/useToggle';
-export const useArrowKeyNavigation: any; // from './hooks/useArrowKeyNavigation';
-export const useIndexOfLastVisibleChild: any; // from './hooks/useIndexOfLastVisibleChild';
-export const useIsVisible: any; // from './hooks/useIsVisible';
 export const
   OverflowScrollContext: any,
   OverflowScroll: any,

src/index.js

@@ -40,6 +40,11 @@ export { default as ModalLayer } from './Modal/ModalLayer';
 export { default as Overlay, OverlayTrigger } from './Overlay';
 export { default as Portal } from './Modal/Portal';
 export { default as Tooltip } from './Tooltip';
+export { default as useWindowSize } from './hooks/useWindowSize';
+export { default as useToggle } from './hooks/useToggle';
+export { default as useArrowKeyNavigation } from './hooks/useArrowKeyNavigation';
+export { default as useIndexOfLastVisibleChild } from './hooks/useIndexOfLastVisibleChild';
+export { default as useIsVisible } from './hooks/useIsVisible';
 
 // // // // // // // // // // // // // // // // // // // // // // // // // // //
 // Things that don't have types
@@ -187,11 +192,6 @@ export { default as Sticky } from './Sticky';
 export { default as SelectableBox } from './SelectableBox';
 export { default as breakpoints } from './utils/breakpoints';
 export { default as Variant } from './utils/constants';
-export { default as useWindowSize } from './hooks/useWindowSize';
-export { default as useToggle } from './hooks/useToggle';
-export { default as useArrowKeyNavigation } from './hooks/useArrowKeyNavigation';
-export { default as useIndexOfLastVisibleChild } from './hooks/useIndexOfLastVisibleChild';
-export { default as useIsVisible } from './hooks/useIsVisible';
 export {
   OverflowScrollContext,
   OverflowScroll,

www/gatsby-config.js

@@ -34,6 +34,7 @@ const plugins = [
     },
   },
   'gatsby-plugin-react-helmet',
+  'gatsby-plugin-typescript',
   {
     resolve: 'gatsby-plugin-manifest',
     options: {

www/src/components/header/Navbar.tsx

@@ -15,7 +15,7 @@ import Search from '../Search';
 
 export interface INavbar {
   siteTitle: string,
-  onMenuClick: () => boolean,
+  onMenuClick: () => void,
   setTarget: React.Dispatch<React.SetStateAction<HTMLButtonElement | null>>,
   onSettingsClick?: () => void,
   menuIsOpen?: boolean,