Initial work, copied from the Shopify provider

framework/saleor/customer/use-customer.tsx

@@ -0,0 +1,27 @@
+import useCustomer, { UseCustomer } from '@commerce/customer/use-customer'
+import { Customer } from '@commerce/types'
+import { SWRHook } from '@commerce/utils/types'
+import { getCustomerQuery, getCustomerToken } from '../utils'
+
+export default useCustomer as UseCustomer<typeof handler>
+
+export const handler: SWRHook<Customer | null> = {
+  fetchOptions: {
+    query: getCustomerQuery,
+  },
+  async fetcher({ options, fetch }) {
+    const data = await fetch<any | null>({
+      ...options,
+      variables: { customerAccessToken: getCustomerToken() },
+    })
+    return data.customer ?? null
+  },
+  useHook: ({ useData }) => (input) => {
+    return useData({
+      swrOptions: {
+        revalidateOnFocus: false,
+        ...input?.swrOptions,
+      },
+    })
+  },
+}