Make ART Concurrent if Legacy Mode is disabled

Updated flowing in from above as well as setStates will now be batched
using "discrete" priority but should still happen same task.

We need to use the right scheduler in tests for act to work properly.

packages/react-art/src/ReactART.js

@@ -7,15 +7,17 @@
 
 import * as React from 'react';
 import ReactVersion from 'shared/ReactVersion';
-import {LegacyRoot} from 'react-reconciler/src/ReactRootTags';
+import {LegacyRoot, ConcurrentRoot} from 'react-reconciler/src/ReactRootTags';
 import {
   createContainer,
   updateContainer,
   injectIntoDevTools,
+  flushSync,
 } from 'react-reconciler/src/ReactFiberReconciler';
 import Transform from 'art/core/transform';
 import Mode from 'art/modes/current';
 import FastNoSideEffects from 'art/modes/fast-noSideEffects';
+import {disableLegacyMode} from 'shared/ReactFeatureFlags';
 
 import {TYPES, childrenAsString} from './ReactARTInternals';
 
@@ -68,13 +70,17 @@ class Surface extends React.Component {
 
     this._mountNode = createContainer(
       this._surface,
-      LegacyRoot,
+      disableLegacyMode ? ConcurrentRoot : LegacyRoot,
       null,
       false,
       false,
       '',
     );
-    updateContainer(this.props.children, this._mountNode, this);
+    // We synchronously flush updates coming from above so that they commit together
+    // and so that refs resolve before the parent life cycles.
+    flushSync(() => {
+      updateContainer(this.props.children, this._mountNode, this);
+    });
   }
 
   componentDidUpdate(prevProps, prevState) {
@@ -84,15 +90,23 @@ class Surface extends React.Component {
       this._surface.resize(+props.width, +props.height);
     }
 
-    updateContainer(this.props.children, this._mountNode, this);
+    // We synchronously flush updates coming from above so that they commit together
+    // and so that refs resolve before the parent life cycles.
+    flushSync(() => {
+      updateContainer(this.props.children, this._mountNode, this);
+    });
 
     if (this._surface.render) {
       this._surface.render();
     }
   }
 
   componentWillUnmount() {
-    updateContainer(null, this._mountNode, this);
+    // We synchronously flush updates coming from above so that they commit together
+    // and so that refs resolve before the parent life cycles.
+    flushSync(() => {
+      updateContainer(null, this._mountNode, this);
+    });
   }
 
   render() {

packages/react-art/src/__tests__/ReactART-test.js

@@ -11,7 +11,8 @@
 
 'use strict';
 
-import * as React from 'react';
+const React = require('react');
+const Scheduler = require('scheduler');
 
 import * as ReactART from 'react-art';
 import ARTSVGMode from 'art/modes/svg';
@@ -22,22 +23,27 @@ import Circle from 'react-art/Circle';
 import Rectangle from 'react-art/Rectangle';
 import Wedge from 'react-art/Wedge';
 
+const {act, waitFor} = require('internal-test-utils');
+
 // Isolate DOM renderer.
 jest.resetModules();
+// share isomorphic
+jest.mock('scheduler', () => Scheduler);
+jest.mock('react', () => React);
 const ReactDOMClient = require('react-dom/client');
-let act = require('internal-test-utils').act;
 
 // Isolate the noop renderer
 jest.resetModules();
+// share isomorphic
+jest.mock('scheduler', () => Scheduler);
+jest.mock('react', () => React);
 const ReactNoop = require('react-noop-renderer');
-const Scheduler = require('scheduler');
 
 let Group;
 let Shape;
 let Surface;
 let TestComponent;
 
-let waitFor;
 let groupRef;
 
 const Missing = {};
@@ -68,6 +74,11 @@ describe('ReactART', () => {
   let container;
 
   beforeEach(() => {
+    jest.resetModules();
+    // share isomorphic
+    jest.mock('scheduler', () => Scheduler);
+    jest.mock('react', () => React);
+
     container = document.createElement('div');
     document.body.appendChild(container);
 
@@ -77,8 +88,6 @@ describe('ReactART', () => {
     Shape = ReactART.Shape;
     Surface = ReactART.Surface;
 
-    ({waitFor} = require('internal-test-utils'));
-
     groupRef = React.createRef();
     TestComponent = class extends React.Component {
       group = groupRef;
@@ -409,8 +418,6 @@ describe('ReactART', () => {
       );
     }
 
-    // Using test renderer instead of the DOM renderer here because async
-    // testing APIs for the DOM renderer don't exist.
     ReactNoop.render(
       <CurrentRendererContext.Provider value="Test">
         <Yield value="A" />
@@ -447,9 +454,11 @@ describe('ReactARTComponents', () => {
   let ReactTestRenderer;
   beforeEach(() => {
     jest.resetModules();
+    // share isomorphic
+    jest.mock('scheduler', () => Scheduler);
+    jest.mock('react', () => React);
     // Isolate test renderer.
     ReactTestRenderer = require('react-test-renderer');
-    act = require('internal-test-utils').act;
   });
 
   it('should generate a <Shape> with props for drawing the Circle', async () => {