Understanding Fiber Architecture

// Assume this is a simplified structure of a Fiber node
const fiberNode = {
    stateNode: null, // The component instance or DOM node
    child: null,      // The first child fiber
    sibling: null,   // The sibling fiber
    return: null     // The parent fiber
    // ... other properties
};

// Create a root Fiber node for our app
const rootFiber = Object.create(fiberNode);
rootFiber.stateNode = document.getElementById('app');

// Function to perform work on a fiber node
function performUnitOfWork(fiber) {
    // Simulate rendering by attaching children to the DOM
    if (fiber.child) {
        fiber.stateNode.appendChild(fiber.child.stateNode);
    }

    // Return the next unit of work
    if (fiber.child) {
        return fiber.child;
    } else {
        let nextFiber = fiber;
        while (nextFiber) {
            if (nextFiber.sibling) {
                return nextFiber.sibling;
            }
            nextFiber = nextFiber.return;
        }
    }
}

// Represents a user-defined component that creates DOM nodes
function MyComponent() {
    // ... component logic
}

// Usage

// Create fiber nodes for our component tree
const myComponentFiber = Object.create(fiberNode);
myComponentFiber.stateNode = new MyComponent();

rootFiber.child = myComponentFiber;
myComponentFiber.return = rootFiber;