@samitouri / QOS-React / commits / 81eef12507

Test that hidden subtrees render/update synchronously

When useSyncScheduling is set to true (as it is in the DOM renderer), we shouldn't give OffscreenPriority to hidden subtrees. Everything should be sync/task.

Andrew Clark committed Feb 27, 2017 at 15:54 UTC 81eef12507cc49dae1f70e44cea5493295eb69cd

1 file changed +35

src/renderers/__tests__/ReactUpdates-test.js

+35

@@ -1189,4 +1189,39 @@ describe('ReactUpdates', () => {

1189 instance.setState(() => null);

1190 expect(ops).toEqual([]);

1191 });

1192 +

1193 + // Will change once we switch to async by default

1194 + it('synchronously renders hidden subtrees', () => {

1195 + let container = document.createElement('div');

1196 + let ops = [];

1197 +

1198 + function Baz() {

1199 + ops.push('Baz');

1200 + return null;

1201 + }

1202 +

1203 + function Bar() {

1204 + ops.push('Bar');

1205 + return null;

1206 + }

1207 +

1208 + function Foo() {

1209 + ops.push('Foo');

1210 + return (

1211 + <div>

1212 + <div hidden={true}><Bar /></div>

1213 + <Baz />

1214 + </div>

1215 + );

1216 + }

1217 +

1218 + // Mount

1219 + ReactDOM.render(<Foo />, container);

1220 + expect(ops).toEqual(['Foo', 'Bar', 'Baz']);

1221 + ops = [];

1222 +

1223 + // Update

1224 + ReactDOM.render(<Foo />, container);

1225 + expect(ops).toEqual(['Foo', 'Bar', 'Baz']);

1226 + });

1227 });