Promise<ConsumerStream> 不可分配给类型 Promise<void>

Question

我想弄清楚为什么在构建过程中会出现此错误 (npm run build):

ERROR: src/setup/kafka/index.ts:147:29 - error TS2322: Type ''.
  Type 'ConsumerStream' is not assignable to type 'void'.
147             shutdown: () => Promise.resolve(stream.destroy()),
                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  src/app.types.ts:26:15
    26     shutdown: () => Promise<void>;
                     ~~~~~~~~~~~~~~~~~~~
    The expected type comes from the return type of this signature.

其中 stream 是一个 kafka.ConsumerStream 实例（参见 node-rdkafka）

stream.destroy()returnsvoid，即destroy(error?: Error): void;

感谢您的回答

Answer 1

ConsumerStream.destroy 的 return 类型是 ConsumerStream（请参阅此答案底部带有链接的类型详细信息）。您可以通过在 stream.destroy 的调用前加上 void operator:

来重构您的方法

TS Playground

import {type ConsumerStream} from 'node-rdkafka';

declare const stream: ConsumerStream;
stream.destroy(); // ConsumerStream

type IncludesShutdown = {
  shutdown: () => Promise<void>;
};

const problematic: IncludesShutdown = {
  shutdown: async () => stream.destroy(), /*
                        ^^^^^^^^^^^^^^^^
Type 'Promise<ConsumerStream>' is not assignable to type 'Promise<void>'.
  Type 'ConsumerStream' is not assignable to type 'void'.(2322) */
};

const ok: IncludesShutdown = {
  shutdown: async () => void stream.destroy(),
};

键入 ConsumerStream['destroy'] 的详细信息：

https://github.com/Blizzard/node-rdkafka/blob/v2.12.0/index.d.ts#L137

export interface ConsumerStream extends Readable {

https://github.com/Blizzard/node-rdkafka/blob/v2.12.0/index.d.ts#L1

import { Readable, ReadableOptions, Writable, WritableOptions } from 'stream';

https://github.com/DefinitelyTyped/DefinitelyTyped/blob/20217c8228ad3837045c450e389fe92e8598cdd7/types/node/stream.d.ts#L411

// declare module 'stream' {
  // class Readable extends Stream implements NodeJS.ReadableStream {
    destroy(error?: Error): this;

Promise<ConsumerStream> 不可分配给类型 Promise<void>

Promise<ConsumerStream> is not assignable to type Promise<void>

node.js

typescript

typescript-typings