Fix request body not being properly cached (#2150)

source/core/index.ts

@@ -1110,6 +1110,7 @@ export default class Request extends Duplex implements RequestEvents<Request> {
 		if (options.cache) {
 			(this._requestOptions as any)._request = request;
 			(this._requestOptions as any).cache = options.cache;
+			(this._requestOptions as any).body = options.body;
 			this._prepareCache(options.cache as StorageAdapter);
 		}
 

test/cache.ts

@@ -1,5 +1,6 @@
 import {Buffer} from 'buffer';
 import {promisify} from 'util';
+import {Readable as ReadableStream} from 'stream';
 import {Agent} from 'http';
 import {gzip} from 'zlib';
 import test from 'ava';
@@ -44,6 +45,34 @@ test('cacheable responses are cached', withServer, async (t, server, got) => {
 	t.is(firstResponse.body, secondResponse.body);
 });
 
+test('cacheable responses to POST requests are cached', withServer, async (t, server, got) => {
+	server.post('/', cacheEndpoint);
+
+	const cache = new Map();
+
+	const firstResponse = await got({method: 'POST', body: 'test', cache});
+	const secondResponse = await got({method: 'POST', body: 'test', cache});
+
+	t.is(cache.size, 1);
+	t.is(firstResponse.body, secondResponse.body);
+});
+
+test('non-cacheable responses to POST requests are not cached', withServer, async (t, server, got) => {
+	server.post('/', cacheEndpoint);
+
+	const cache = new Map();
+
+	// POST requests with streams are not cached
+	const body1 = ReadableStream.from(Buffer.from([1, 2, 3]));
+	const body2 = ReadableStream.from(Buffer.from([1, 2, 3]));
+
+	const firstResponseInt = Number((await got({method: 'POST', body: body1, cache})).body);
+	const secondResponseInt = Number((await got({method: 'POST', body: body2, cache})).body);
+
+	t.is(cache.size, 0);
+	t.true(firstResponseInt < secondResponseInt);
+});
+
 test('cached response is re-encoded to current encoding option', withServer, async (t, server, got) => {
 	server.get('/', cacheEndpoint);