Add Next.js ESLint (#425)

* Added Next.js eslint

* added eslint to lint-staged

* Added eslint config for prettier

* Fixed eslint issues in multiple files

* Fixed error in linter

.eslintrc

@@ -0,0 +1,6 @@
+{
+  "extends": ["next", "prettier"],
+  "rules": {
+    "react/no-unescaped-entities": "off"
+  }
+}

components/cart/CartItem/CartItem.tsx

@@ -70,6 +70,9 @@ const CartItem = ({
     if (item.quantity !== Number(quantity)) {
       setQuantity(item.quantity)
     }
+    // TODO: currently not including quantity in deps is intended, but we should
+    // do this differently as it could break easily
+    // eslint-disable-next-line react-hooks/exhaustive-deps
   }, [item.quantity])
 
   return (

components/common/Footer/Footer.tsx

@@ -73,7 +73,7 @@ const Footer: FC<Props> = ({ className, pages }) => {
           <div className="flex items-center text-primary text-sm">
             <span className="text-primary">Created by</span>
             <a
-              rel="noopener"
+              rel="noopener noreferrer"
               href="https://vercel.com"
               aria-label="Vercel.com Link"
               target="_blank"

components/common/Layout/Layout.tsx

@@ -24,7 +24,7 @@ const Loading = () => (
 )
 
 const dynamicProps = {
-  loading: () => <Loading />,
+  loading: Loading,
 }
 
 const SignUpView = dynamic(

components/common/Searchbar/Searchbar.tsx

@@ -1,4 +1,4 @@
-import { FC, InputHTMLAttributes, useEffect, useMemo } from 'react'
+import { FC, memo, useEffect } from 'react'
 import cn from 'classnames'
 import s from './Searchbar.module.css'
 import { useRouter } from 'next/router'
@@ -13,7 +13,7 @@ const Searchbar: FC<Props> = ({ className, id = 'search' }) => {
 
   useEffect(() => {
     router.prefetch('/search')
-  }, [])
+  }, [router])
 
   const handleKeyUp = (e: React.KeyboardEvent<HTMLInputElement>) => {
     e.preventDefault()
@@ -32,8 +32,7 @@ const Searchbar: FC<Props> = ({ className, id = 'search' }) => {
     }
   }
 
-  return useMemo(
-    () => (
+  return (
     <div className={cn(s.root, className)}>
       <label className="hidden" htmlFor={id}>
         Search
@@ -55,9 +54,7 @@ const Searchbar: FC<Props> = ({ className, id = 'search' }) => {
         </svg>
       </div>
     </div>
-    ),
-    []
   )
 }
 
-export default Searchbar
+export default memo(Searchbar)

components/product/ProductOptions/ProductOptions.tsx

@@ -1,15 +1,19 @@
+import { memo } from 'react'
 import { Swatch } from '@components/product'
 import type { ProductOption } from '@commerce/types/product'
 import { SelectedOptions } from '../helpers'
-import React from 'react'
+
 interface ProductOptionsProps {
   options: ProductOption[]
   selectedOptions: SelectedOptions
   setSelectedOptions: React.Dispatch<React.SetStateAction<SelectedOptions>>
 }
 
-const ProductOptions: React.FC<ProductOptionsProps> = React.memo(
-  ({ options, selectedOptions, setSelectedOptions }) => {
+const ProductOptions: React.FC<ProductOptionsProps> = ({
+  options,
+  selectedOptions,
+  setSelectedOptions,
+}) => {
   return (
     <div>
       {options.map((opt) => (
@@ -31,8 +35,7 @@ const ProductOptions: React.FC<ProductOptionsProps> = React.memo(
                     setSelectedOptions((selectedOptions) => {
                       return {
                         ...selectedOptions,
-                          [opt.displayName.toLowerCase()]:
-                            v.label.toLowerCase(),
+                        [opt.displayName.toLowerCase()]: v.label.toLowerCase(),
                       }
                     })
                   }}
@@ -44,7 +47,6 @@ const ProductOptions: React.FC<ProductOptionsProps> = React.memo(
       ))}
     </div>
   )
-  }
-)
+}
 
-export default ProductOptions
+export default memo(ProductOptions)

components/product/ProductSidebar/ProductSidebar.tsx

@@ -23,7 +23,7 @@ const ProductSidebar: FC<ProductSidebarProps> = ({ product, className }) => {
 
   useEffect(() => {
     selectDefaultOptionFromProduct(product, setSelectedOptions)
-  }, [])
+  }, [product])
 
   const variant = getProductVariant(product, selectedOptions)
   const addToCart = async () => {

components/product/ProductSlider/ProductSlider.tsx

@@ -66,17 +66,13 @@ const ProductSlider: React.FC<ProductSliderProps> = ({
         event.preventDefault()
     }
 
-    sliderContainerRef.current!.addEventListener(
-      'touchstart',
-      preventNavigation
-    )
+    const slider = sliderContainerRef.current!
+
+    slider.addEventListener('touchstart', preventNavigation)
 
     return () => {
-      if (sliderContainerRef.current) {
-        sliderContainerRef.current!.removeEventListener(
-          'touchstart',
-          preventNavigation
-        )
+      if (slider) {
+        slider.removeEventListener('touchstart', preventNavigation)
       }
     }
   }, [])

components/product/ProductSliderControl/ProductSliderControl.tsx

@@ -1,15 +1,14 @@
+import { FC, MouseEventHandler, memo } from 'react'
 import cn from 'classnames'
-import React from 'react'
 import s from './ProductSliderControl.module.css'
 import { ArrowLeft, ArrowRight } from '@components/icons'
 
 interface ProductSliderControl {
-  onPrev: React.MouseEventHandler<HTMLButtonElement>
-  onNext: React.MouseEventHandler<HTMLButtonElement>
+  onPrev: MouseEventHandler<HTMLButtonElement>
+  onNext: MouseEventHandler<HTMLButtonElement>
 }
 
-const ProductSliderControl: React.FC<ProductSliderControl> = React.memo(
-  ({ onPrev, onNext }) => (
+const ProductSliderControl: FC<ProductSliderControl> = ({ onPrev, onNext }) => (
   <div className={s.control}>
     <button
       className={cn(s.leftControl)}
@@ -26,6 +25,6 @@ const ProductSliderControl: React.FC<ProductSliderControl> = React.memo(
       <ArrowRight />
     </button>
   </div>
-  )
 )
-export default ProductSliderControl
+
+export default memo(ProductSliderControl)

components/search.tsx

@@ -7,7 +7,7 @@ import { useRouter } from 'next/router'
 import { Layout } from '@components/common'
 import { ProductCard } from '@components/product'
 import type { Product } from '@commerce/types/product'
-import { Container, Grid, Skeleton } from '@components/ui'
+import { Container, Skeleton } from '@components/ui'
 
 import useSearch from '@framework/product/use-search'
 

components/ui/Modal/Modal.tsx

@@ -27,13 +27,15 @@ const Modal: FC<ModalProps> = ({ children, onClose }) => {
   )
 
   useEffect(() => {
-    if (ref.current) {
-      disableBodyScroll(ref.current, { reserveScrollBarGap: true })
+    const modal = ref.current
+
+    if (modal) {
+      disableBodyScroll(modal, { reserveScrollBarGap: true })
       window.addEventListener('keydown', handleKey)
     }
     return () => {
-      if (ref && ref.current) {
-        enableBodyScroll(ref.current)
+      if (modal) {
+        enableBodyScroll(modal)
       }
       clearAllBodyScrollLocks()
       window.removeEventListener('keydown', handleKey)

components/ui/Rating/Rating.tsx

@@ -1,4 +1,4 @@
-import React, { FC } from 'react'
+import { FC, memo } from 'react'
 import rangeMap from '@lib/range-map'
 import { Star } from '@components/icons'
 import cn from 'classnames'
@@ -7,8 +7,7 @@ export interface RatingProps {
   value: number
 }
 
-const Quantity: React.FC<RatingProps> = React.memo(({ value = 5 }) => {
-  return (
+const Quantity: FC<RatingProps> = ({ value = 5 }) => (
   <div className="flex flex-row py-6 text-accent-9">
     {rangeMap(5, (i) => (
       <span
@@ -21,7 +20,6 @@ const Quantity: React.FC<RatingProps> = React.memo(({ value = 5 }) => {
       </span>
     ))}
   </div>
-  )
-})
+)
 
-export default Quantity
+export default memo(Quantity)

components/ui/Sidebar/Sidebar.tsx

@@ -16,13 +16,14 @@ const Sidebar: FC<SidebarProps> = ({ children, onClose }) => {
   const ref = useRef() as React.MutableRefObject<HTMLDivElement>
 
   useEffect(() => {
-    if (ref.current) {
-      disableBodyScroll(ref.current, { reserveScrollBarGap: true })
+    const sidebar = ref.current
+
+    if (sidebar) {
+      disableBodyScroll(sidebar, { reserveScrollBarGap: true })
     }
+
     return () => {
-      if (ref && ref.current) {
-        enableBodyScroll(ref.current)
-      }
+      if (sidebar) enableBodyScroll(sidebar)
       clearAllBodyScrollLocks()
     }
   }, [])

lib/focus-trap.tsx

@@ -55,10 +55,13 @@ export default function FocusTrap({ children, focusFirst = false }: Props) {
     }
   }, [root, children])
 
-  return React.createElement('div', {
+  return React.createElement(
+    'div',
+    {
       ref: root,
-    children,
       className: 'outline-none focus-trap',
       tabIndex: -1,
-  })
+    },
+    children
+  )
 }

lib/search.tsx

@@ -18,10 +18,10 @@ export function useSearchMeta(asPath: string) {
       c = parts[4]
     }
 
-    setPathname(path)
+    if (path !== pathname) setPathname(path)
     if (c !== category) setCategory(c)
     if (b !== brand) setBrand(b)
-  }, [asPath])
+  }, [asPath, pathname, category, brand])
 
   return { pathname, category, brand }
 }

package.json

@@ -6,6 +6,7 @@
     "build": "next build",
     "start": "next start",
     "analyze": "BUNDLE_ANALYZE=both yarn build",
+    "lint": "next lint",
     "prettier-fix": "prettier --write .",
     "find:unused": "npx next-unused",
     "generate": "graphql-codegen",
@@ -63,6 +64,9 @@
     "@types/node": "^15.12.4",
     "@types/react": "^17.0.8",
     "deepmerge": "^4.2.2",
+    "eslint": "^7.31.0",
+    "eslint-config-next": "^11.0.1",
+    "eslint-config-prettier": "^8.3.0",
     "graphql": "^15.5.1",
     "husky": "^6.0.0",
     "lint-staged": "^11.0.0",
@@ -78,6 +82,7 @@
   },
   "lint-staged": {
     "**/*.{js,jsx,ts,tsx}": [
+      "eslint",
       "prettier --write",
       "git add"
     ],