Function createMutation

packages/svelte-query/src/createMutation.ts:13–54

(
  options: StoreOrVal<
    CreateMutationOptions<TData, TError, TVariables, TOnMutateResult>
  >,
  queryClient?: QueryClient,
)

import type { DefaultError, QueryClient } from '@tanstack/query-core'

export function createMutation<
  TData = unknown,
  TError = DefaultError,
  TVariables = void,
  TOnMutateResult = unknown,
>(
  options: StoreOrVal<
    CreateMutationOptions<TData, TError, TVariables, TOnMutateResult>
  >,
  queryClient?: QueryClient,
): CreateMutationResult<TData, TError, TVariables, TOnMutateResult> {
  const client = useQueryClient(queryClient)

  const optionsStore = isSvelteStore(options) ? options : readable(options)

  const observer = new MutationObserver<
    TData,
    TError,
    TVariables,
    TOnMutateResult
  >(client, get(optionsStore))
  let mutate: CreateMutateFunction<TData, TError, TVariables, TOnMutateResult>

  optionsStore.subscribe(($options) => {
    mutate = (variables, mutateOptions) => {
      observer.mutate(variables, mutateOptions).catch(noop)
    }
    observer.setOptions($options)
  })

  const result = readable(observer.getCurrentResult(), (set) => {
    return observer.subscribe(notifyManager.batchCalls((val) => set(val)))
  })

  const { subscribe } = derived(result, ($result) => ({
    ...$result,
    mutate,
    mutateAsync: $result.mutate,
  }))

  return { subscribe }
}