Add safe default fallback for scrollEventThrottle and remove return from queueMicrotask

[tjzel]

Summary

• Remove redundant return of -1 from queueMicrotask that remained there when it was changed from setImmediate.
• Add safe default fallbacks for scrollEventThrottle in Animated.ScrollView and Animated.FlatList.

We go from

if (!restProps.scrollEventThrottle) {
  restProps.scrollEventThrottle = 1;
}

to

  if (!('scrollEventThrottle' in restProps)) {
    restProps.scrollEventThrottle = 1;
  }

Because if user deliberately sets scrollEventThrottle to 0 we would override it.

Test plan

Test code for scrollEventThrottle, just fiddle a bit with this prop and see the outcome in the console.

import React from 'react';
import { ScrollView, View, StyleSheet, FlatList } from 'react-native';
import Animated from 'react-native-reanimated';

const data = [1];

export default function App() {
  const lastTimestamp = React.useRef(performance.now());
  function onScroll() {
    const now = performance.now();
    const delta = now - lastTimestamp.current;
    lastTimestamp.current = now;
    console.log('onScroll', delta);
  }

  return (
    <View style={styles.container}>
      <ScrollView onScroll={onScroll}>
        <View style={[styles.item, { backgroundColor: 'pink' }]} />
      </ScrollView>
      <Animated.FlatList
        data={data}
        onScroll={onScroll}
        renderItem={() => (
          <View style={[styles.item, { backgroundColor: 'navy' }]} />
        )}
      />
      <FlatList
        data={data}
        onScroll={onScroll}
        renderItem={() => (
          <View style={[styles.item, { backgroundColor: 'yellow' }]} />
        )}
      />
    </View>
  );
}

const styles = StyleSheet.create({
  container: {
    flexDirection: 'row',
  },
  item: {
    height: 4000,
    flex: 1 / 3,
  },
});

[tomekzaw]

Suggested change

	// there are 960FPS screens.
	// there are 960 fps screens.

[tomekzaw]

Let's use exportedModule as for now.

[tomekzaw]

Suggested change

	// there are 960FPS screens.
	// there are 960 fps screens.

[tomekzaw]

why?

[tjzel]

Look at line #9 😎

[tomekzaw]

approvele