Updated useCart hook

lib/bigcommerce/cart/index.tsx

@@ -1,21 +1,48 @@
+import { HookFetcher, HookDeps } from '@lib/commerce/utils/types'
 import { useCart as useCommerceCart } from '@lib/commerce/cart'
 import type { Cart } from '../api/cart'
 
+const defaultOpts = {
+  url: '/api/bigcommerce/cart',
+}
+
 export type { Cart }
 
-export function useCart() {
-  const cart = useCommerceCart<Cart | null>()
-
-  // Uses a getter to only calculate the prop when required
-  // cart.data is also a getter and it's better to not trigger it early
-  Object.defineProperty(cart, 'isEmpty', {
-    get() {
-      return Object.values(cart.data?.line_items ?? {}).every(
-        (items) => !items.length
-      )
-    },
-    set: (x) => x,
+export const fetcher: HookFetcher<Cart | null, HookDeps[]> = (
+  options,
+  _,
+  fetch
+) => {
+  return fetch({
+    url: options?.url,
+    query: options?.query,
   })
-
-  return cart
 }
+
+function extend(customFetcher: typeof fetcher) {
+  const useCart = () => {
+    const cart = useCommerceCart<Cart | null>(
+      [defaultOpts.url, undefined],
+      customFetcher
+    )
+
+    // Uses a getter to only calculate the prop when required
+    // cart.data is also a getter and it's better to not trigger it early
+    Object.defineProperty(cart, 'isEmpty', {
+      get() {
+        return Object.values(cart.data?.line_items ?? {}).every(
+          (items) => !items.length
+        )
+      },
+      set: (x) => x,
+    })
+
+    return cart
+  }
+
+  useCart.extend = extend
+
+  return useCart
+}
+
+export const useCart = extend(fetcher)

lib/commerce/cart/index.tsx

@@ -1,22 +1,24 @@
 import useSWR, { responseInterface } from 'swr'
 import Cookies from 'js-cookie'
+import { HookDeps, HookFetcher } from '../utils/types'
 import { useCommerce } from '..'
 
-const CART_API = '/api/bigcommerce/cart'
-
 export type CartResponse<C> = responseInterface<C, Error> & {
   isEmpty: boolean
 }
 
-function useCart<C>() {
+export function useCart<T>(
+  deps: [string | undefined, string | undefined, ...HookDeps[]],
+  fetcherFn: HookFetcher<T, HookDeps[]>
+) {
   const { fetcherRef, cartCookie } = useCommerce()
-  const fetcher = (url?: string, query?: string) =>
-    Cookies.get(cartCookie) ? fetcherRef.current({ url, query }) : null
-  const response = useSWR([CART_API, undefined], fetcher, {
+  const fetcher = (url?: string, query?: string, ...args: HookDeps[]) =>
+    Cookies.get(cartCookie)
+      ? fetcherFn({ url, query }, args, fetcherRef.current)
+      : null
+  const response = useSWR(deps, fetcher, {
     revalidateOnFocus: false,
   })
 
-  return Object.assign(response, { isEmpty: true }) as CartResponse<C>
+  return Object.assign(response, { isEmpty: true }) as CartResponse<T>
 }
-
-export { useCart }

lib/commerce/utils/types.ts

@@ -20,3 +20,5 @@ export type HookFetcherOptions = {
   url?: string
   method?: string
 }
+
+export type HookDeps = string | number | undefined[]