Initial work, copied from the Shopify provider

framework/saleor/cart/use-remove-item.tsx

@@ -0,0 +1,71 @@
+import { useCallback } from 'react'
+import type {
+  MutationHookContext,
+  HookFetcherContext,
+} from '@commerce/utils/types'
+import { RemoveCartItemBody } from '@commerce/types'
+import { ValidationError } from '@commerce/utils/errors'
+import useRemoveItem, {
+  RemoveItemInput as RemoveItemInputBase,
+  UseRemoveItem,
+} from '@commerce/cart/use-remove-item'
+import useCart from './use-cart'
+import {
+  checkoutLineItemRemoveMutation,
+  getCheckoutId,
+  checkoutToCart,
+} from '../utils'
+import { Cart, LineItem } from '../types'
+import { Mutation, MutationCheckoutLineItemsRemoveArgs } from '../schema'
+
+export type RemoveItemFn<T = any> = T extends LineItem
+  ? (input?: RemoveItemInput<T>) => Promise<Cart | null>
+  : (input: RemoveItemInput<T>) => Promise<Cart | null>
+
+export type RemoveItemInput<T = any> = T extends LineItem
+  ? Partial<RemoveItemInputBase>
+  : RemoveItemInputBase
+
+export default useRemoveItem as UseRemoveItem<typeof handler>
+
+export const handler = {
+  fetchOptions: {
+    query: checkoutLineItemRemoveMutation,
+  },
+  async fetcher({
+    input: { itemId },
+    options,
+    fetch,
+  }: HookFetcherContext<RemoveCartItemBody>) {
+    const data = await fetch<Mutation, MutationCheckoutLineItemsRemoveArgs>({
+      ...options,
+      variables: { checkoutId: getCheckoutId(), lineItemIds: [itemId] },
+    })
+    return checkoutToCart(data.checkoutLineItemsRemove)
+  },
+  useHook: ({
+    fetch,
+  }: MutationHookContext<Cart | null, RemoveCartItemBody>) => <
+    T extends LineItem | undefined = undefined
+  >(
+    ctx: { item?: T } = {}
+  ) => {
+    const { item } = ctx
+    const { mutate } = useCart()
+    const removeItem: RemoveItemFn<LineItem> = async (input) => {
+      const itemId = input?.id ?? item?.id
+
+      if (!itemId) {
+        throw new ValidationError({
+          message: 'Invalid input used for this operation',
+        })
+      }
+
+      const data = await fetch({ input: { itemId } })
+      await mutate(data, false)
+      return data
+    }
+
+    return useCallback(removeItem as RemoveItemFn<T>, [fetch, mutate])
+  },
+}