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// Copyright 2018-2023 the Deno authors. All rights reserved. MIT license.
export class RetryError extends Error {  constructor(cause: unknown, count: number) {    super(`Exceeded max retry count (${count})`);    this.name = "RetryError";    this.cause = cause;  }}
export interface RetryOptions {  /** How much to backoff after each retry. This is `2` by default. */  multiplier?: number;  /** The maximum milliseconds between retries. This is `60000` by default. */  maxTimeout?: number;  /** The maximum amount of retries until failure. This is `5` by default. */  maxAttempts?: number;  /** The inital and minimum amount of milliseconds between retries. This is `1000` by default. */  minTimeout?: number;}
const defaultRetryOptions = {  multiplier: 2,  maxTimeout: 60000,  maxAttempts: 5,  minTimeout: 1000,};
/** * Creates a retry promise which resolves to the value of the input using exponential backoff. * If the input promise throws, it will be retried `maxAttempts` number of times. * It will retry the input every certain amount of milliseconds, starting at `minTimeout` and multiplying by the `multiplier` until it reaches the `maxTimeout` * * @example * ```typescript * import { retry } from "https://deno.land/std@$STD_VERSION/async/mod.ts"; * const req = async () => { *  // some function that throws sometimes * }; * * // Below resolves to the first non-error result of `req` * const retryPromise = await retry(req, { *  multiplier: 2, *  maxTimeout: 60000, *  maxAttempts: 5, *  minTimeout: 100, * });``` */export async function retry<T>(  fn: (() => Promise<T>) | (() => T),  opts?: RetryOptions,) {  const options: Required<RetryOptions> = {    ...defaultRetryOptions,    ...opts,  };
  if (options.maxTimeout >= 0 && options.minTimeout > options.maxTimeout) {    throw new RangeError("minTimeout is greater than maxTimeout");  }
  let timeout = options.minTimeout;  let error: unknown;
  for (let i = 0; i < options.maxAttempts; i++) {    try {      return await fn();    } catch (err) {      await new Promise((r) => setTimeout(r, timeout));      timeout *= options.multiplier;      timeout = Math.max(timeout, options.minTimeout);      if (options.maxTimeout >= 0) {        timeout = Math.min(timeout, options.maxTimeout);      }      error = err;    }  }
  throw new RetryError(error, options.maxAttempts);}