Improve tests

test/http.ts

@@ -1,4 +1,5 @@
 import test from 'ava';
+import getStream = require('get-stream');
 import got, {HTTPError, UnsupportedProtocolError} from '../source';
 import withServer from './helpers/with-server';
 
@@ -82,6 +83,28 @@ test('custom `options.encoding`', withServer, async (t, server, got) => {
 	t.is(data, Buffer.from(string).toString('base64'));
 });
 
+test('`options.encoding` doesn\'t affect streams', withServer, async (t, server, got) => {
+	const string = 'ok';
+
+	server.get('/', (_request, response) => {
+		response.end(string);
+	});
+
+	const data = await getStream(got.stream({encoding: 'base64'}));
+	t.is(data, string);
+});
+
+test('`got.stream(...).setEncoding(...)` works', withServer, async (t, server, got) => {
+	const string = 'ok';
+
+	server.get('/', (_request, response) => {
+		response.end(string);
+	});
+
+	const data = await getStream(got.stream('').setEncoding('base64'));
+	t.is(data, Buffer.from(string).toString('base64'));
+});
+
 test('`searchParams` option', withServer, async (t, server, got) => {
 	server.get('/', (request, response) => {
 		t.is(request.query.recent, 'true');