Warn about nested renders

Author: acdlite

scripts/fiber/tests-passing-except-dev.txt

@@ -56,9 +56,6 @@ src/renderers/__tests__/ReactComponentTreeHook-test.js
 * registers inlined text nodes
 * works
 
-src/renderers/__tests__/ReactCompositeComponent-test.js
-* should disallow nested render calls
-
 src/renderers/__tests__/ReactHostOperationHistoryHook-test.js
 * gets recorded for host roots
 * gets recorded for composite roots

scripts/fiber/tests-passing.txt

@@ -639,6 +639,7 @@ src/renderers/__tests__/ReactCompositeComponent-test.js
 * should pass context when re-rendered
 * unmasked context propagates through updates
 * should trigger componentWillReceiveProps for context changes
+* should disallow nested render calls
 * only renders once if updated in componentWillReceiveProps
 * only renders once if updated in componentWillReceiveProps when batching
 * should update refs if shouldComponentUpdate gives false

src/renderers/__tests__/ReactCompositeComponent-test.js

@@ -1028,11 +1028,11 @@ describe('ReactCompositeComponent', () => {
 
     ReactTestUtils.renderIntoDocument(<Outer />);
     expectDev(console.error.calls.count()).toBe(1);
-    expectDev(console.error.calls.argsFor(0)[0]).toBe(
-      'Warning: _renderNewRootComponent(): Render methods should ' +
-      'be a pure function of props and state; triggering nested component ' +
-      'updates from render is not allowed. If necessary, trigger nested ' +
-      'updates in componentDidUpdate.\n\nCheck the render method of Outer.'
+    expectDev(console.error.calls.argsFor(0)[0]).toMatch(
+      'Render methods should be a pure function of props and state; ' +
+      'triggering nested component updates from render is not allowed. If ' +
+      'necessary, trigger nested updates in componentDidUpdate.\n\nCheck the ' +
+      'render method of Outer.'
     );
   });
 

src/renderers/shared/fiber/ReactFiberReconciler.js

@@ -31,6 +31,9 @@ var ReactFiberScheduler = require('ReactFiberScheduler');
 
 if (__DEV__) {
   var ReactFiberInstrumentation = require('ReactFiberInstrumentation');
+  var warning = require('warning');
+  var ReactCurrentOwner = require('ReactCurrentOwner');
+  var { getComponentName } = require('ReactFiberTreeReflection');
 }
 
 var { findCurrentHostFiber } = require('ReactFiberTreeReflection');
@@ -143,6 +146,21 @@ module.exports = function<T, P, I, TI, PI, C, CX, PL>(
   } = ReactFiberScheduler(config);
 
   function scheduleTopLevelUpdate(current : Fiber, element : ReactNodeList, callback : ?Function) {
+    if (__DEV__) {
+      const owner = ReactCurrentOwner.current;
+      if (owner && typeof owner.tag === 'number') {
+        const ownerFiber : Fiber = (owner : any);
+        warning(
+          false,
+          'Render methods should be a pure function of props and state; ' +
+          'triggering nested component updates from render is not allowed. ' +
+          'If necessary, trigger nested updates in componentDidUpdate.\n\n' +
+          'Check the render method of %s.',
+          getComponentName(ownerFiber)
+        );
+      }
+    }
+
     const priorityLevel = getPriorityContext();
     const nextState = { element };
     addTopLevelUpdate(current, nextState, callback || null, priorityLevel);