Fix the retry math (#653)

readme.md

@@ -264,7 +264,7 @@ An object representing `retries`, `methods`, `statusCodes` and `maxRetryAfter` f
 If `maxRetryAfter` is set to `undefined`, it will use `options.timeout`.<br>
 If [`Retry-After`](https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Retry-After) header is greater than `maxRetryAfter`, it will cancel the request.
 
-Delays between retries counts with function `1000 * Math.pow(2, retry) + Math.random() * 100`, where `retry` is attempt number (starts from 0).
+Delays between retries counts with function `1000 * Math.pow(2, retry) + Math.random() * 100`, where `retry` is attempt number (starts from 1).
 
 The `retries` property can be a `number` or a `function` with `retry` and `error` arguments. The function must return a delay in milliseconds (`0` return value cancels retry).
 

source/normalize-arguments.js

@@ -236,7 +236,7 @@ const normalize = (url, options, defaults) => {
 			}
 
 			const noise = Math.random() * 100;
-			return ((1 << iteration) * 1000) + noise;
+			return ((2 ** (iteration - 1)) * 1000) + noise;
 		};
 	}
 

source/request-as-event-emitter.js

@@ -27,7 +27,6 @@ module.exports = (options, input) => {
 	let redirectString;
 	let uploadBodySize;
 	let retryCount = 0;
-	let retryTries = 0;
 	let shouldAbort = false;
 
 	const setCookie = options.cookieJar ? util.promisify(options.cookieJar.setCookie.bind(options.cookieJar)) : null;
@@ -227,7 +226,7 @@ module.exports = (options, input) => {
 		let backoff;
 
 		try {
-			backoff = options.retry.retries(++retryTries, error);
+			backoff = options.retry.retries(++retryCount, error);
 		} catch (error2) {
 			emitter.emit('error', error2);
 			return;
@@ -241,7 +240,6 @@ module.exports = (options, input) => {
 						await hook(options, error, retryCount);
 					}
 
-					retryCount++;
 					await get(options);
 				} catch (error) {
 					emitter.emit('error', error);