framer-motion/dist/es/render/utils/motion-values.mjs

A simple and powerful JavaScript animation library

import { isMotionValue, motionValue } from 'motion-dom';

function updateMotionValuesFromProps(element, next, prev) {
    for (const key in next) {
        const nextValue = next[key];
        const prevValue = prev[key];
        if (isMotionValue(nextValue)) {
            /**
             * If this is a motion value found in props or style, we want to add it
             * to our visual element's motion value map.
             */
            element.addValue(key, nextValue);
        }
        else if (isMotionValue(prevValue)) {
            /**
             * If we're swapping from a motion value to a static value,
             * create a new motion value from that
             */
            element.addValue(key, motionValue(nextValue, { owner: element }));
        }
        else if (prevValue !== nextValue) {
            /**
             * If this is a flat value that has changed, update the motion value
             * or create one if it doesn't exist. We only want to do this if we're
             * not handling the value with our animation state.
             */
            if (element.hasValue(key)) {
                const existingValue = element.getValue(key);
                if (existingValue.liveStyle === true) {
                    existingValue.jump(nextValue);
                }
                else if (!existingValue.hasAnimated) {
                    existingValue.set(nextValue);
                }
            }
            else {
                const latestValue = element.getStaticValue(key);
                element.addValue(key, motionValue(latestValue !== undefined ? latestValue : nextValue, { owner: element }));
            }
        }
    }
    // Handle removed values
    for (const key in prev) {
        if (next[key] === undefined)
            element.removeValue(key);
    }
    return next;
}

export { updateMotionValuesFromProps };