How to use the preact.options.vnode function in preact

// store a reference to the "current component" vnode
let oldDiff = options._diff || options.__b
options._diff = options.__b = vnode => {
  componentNode = vnode
  if (oldDiff) oldDiff(vnode)
}

// reset component reference at end of diffing:
let oldDiffed = options.diffed
options.diffed = vnode => {
  if (componentNode === vnode) componentNode = null
  if (oldDiffed) oldDiffed(vnode)
}

// our vnode hook looks up the associated component
let old = options.vnode
options.vnode = vnode => {
  const component = componentNode && (componentNode._component || componentNode.__c)
  if (component) {

    if(component.constructor.css){
      const styleId = getStyleId(component.constructor)
      appendStyle(component.constructor.css, styleId);
      (vnode.props || (vnode.props = {}))[styleId] = ''
    }
  }
  if (old) old(vnode)
}

if (!roots.has(root)) roots.add(root);
		});

		onCommitUnmount = catchErrors(vnode => {
			hook.onCommitFiberUnmount(rid, vnode);
		});
	})();

	// Store (possible) previous hooks so that we don't overwrite them
	let prevVNodeHook = options.vnode;
	let prevCommitRoot = options._commit;
	let prevBeforeUnmount = options.unmount;
	let prevBeforeDiff = options._diff;
	let prevAfterDiff = options.diffed;

	options.vnode = vnode => {
		// Tiny performance improvement by initializing fields as doubles
		// from the start. `performance.now()` will always return a double.
		// See https://github.com/facebook/react/issues/14365
		// and https://slidr.io/bmeurer/javascript-engine-fundamentals-the-good-the-bad-and-the-ugly
		vnode.startTime = NaN;
		vnode.endTime = NaN;

		vnode.startTime = 0;
		vnode.endTime = -1;
		if (prevVNodeHook) prevVNodeHook(vnode);
	};

	options._diff = vnode => {
		vnode.startTime = now();
		if (prevBeforeDiff != null) prevBeforeDiff(vnode);
	};

/* istanbul ignore next */
			set(v) {
				this['UNSAFE_' + key] = v;
			}
		});
	}
}

let classNameDescriptor = {
	configurable: true,
	get() {
		return this.class;
	}
};

let oldVNodeHook = options.vnode;
options.vnode = vnode => {
	vnode.$$typeof = REACT_ELEMENT_TYPE;

	let type = vnode.type;
	let props = vnode.props;

	// Apply DOM VNode compat
	if (typeof type != 'function') {
		// Apply defaultValue to value
		if (props.defaultValue) {
			if (!props.value && props.value !== 0) {
				props.value = props.defaultValue;
			}
			delete props.defaultValue;
		}

onCommitRoot = catchErrors(root => {
			// Empty root
			if (root.type === Fragment && root._children.length == 0) return;

			let roots = hook.getFiberRoots(rid);
			root = helpers.handleCommitFiberRoot(root);
			if (!roots.has(root)) roots.add(root);
		});

		onCommitUnmount = catchErrors(vnode => {
			hook.onCommitFiberUnmount(rid, vnode);
		});
	})();

	// Store (possible) previous hooks so that we don't overwrite them
	let prevVNodeHook = options.vnode;
	let prevCommitRoot = options._commit;
	let prevBeforeUnmount = options.unmount;
	let prevBeforeDiff = options._diff;
	let prevAfterDiff = options.diffed;

	options.vnode = vnode => {
		// Tiny performance improvement by initializing fields as doubles
		// from the start. `performance.now()` will always return a double.
		// See https://github.com/facebook/react/issues/14365
		// and https://slidr.io/bmeurer/javascript-engine-fundamentals-the-good-the-bad-and-the-ugly
		vnode.startTime = NaN;
		vnode.endTime = NaN;

		vnode.startTime = 0;
		vnode.endTime = -1;
		if (prevVNodeHook) prevVNodeHook(vnode);

function installShallowRenderHook() {
  if (shallowRenderHookInstalled) {
    return;
  }
  const prevHook = options.vnode;
  options.vnode = vnode => {
    if (shallowRenderActive) {
      shallowRenderVNode(vnode as VNodeExtensions);
    }
    if (prevHook) {
      prevHook(vnode);
    }
  };
  shallowRenderHookInstalled = true;
}

import { options } from 'preact';

const classNameDescriptor = {
  enumerable: false,
  configurable: true,
  get () {
    return this.class;
  },
  set (value) {
    this.class = value;
  }
};

const old = options.vnode;
options.vnode = vnode => {
  const a = vnode.attributes;
  if (a != null) {
    if ('className' in a) {
      a.class = a.className;
    }
    if ('class' in a) {
      Object.defineProperty(a, 'className', classNameDescriptor);
    }
  }
  if (old != null) old(vnode);
};

if (oldDiffed) oldDiffed(vnode);
	};

	options._diff = vnode => {
		if (isPossibleOwner(vnode)) {
			renderStack.push(vnode);
		}
		if (oldDiff) oldDiff(vnode);
	};

	options._root = (vnode, parent) => {
		ownerStack = [];
		if (oldRoot) oldRoot(vnode, parent);
	};

	options.vnode = vnode => {
		vnode._owner =
			ownerStack.length > 0 ? ownerStack[ownerStack.length - 1] : null;
		if (oldVNode) oldVNode(vnode);
	};

	options._render = vnode => {
		if (isPossibleOwner(vnode)) {
			ownerStack.push(vnode);
		}

		if (oldRender) oldRender(vnode);
	};
}

},
	set(v) {
		this.attributes = v;
	},
	configurable: true
});

let oldEventHook = options.event;
options.event = e => {
	if (oldEventHook) e = oldEventHook(e);
	e.persist = Object;
	e.nativeEvent = e;
	return e;
};

let oldVnodeHook = options.vnode;
options.vnode = vnode => {
	if (!vnode.preactCompatUpgraded) {
		vnode.preactCompatUpgraded = true;

		let tag = vnode.nodeName,
			attrs = (vnode.attributes = vnode.attributes == null ? {} : extend({}, vnode.attributes));

		if (typeof tag === 'function') {
			if (tag[COMPONENT_WRAPPER_KEY] === true || (tag.prototype && 'isReactComponent' in tag.prototype)) {
				if (vnode.children && String(vnode.children) === '') vnode.children = undefined;
				if (vnode.children) attrs.children = vnode.children;

				if (!vnode.preactCompatNormalized) {
					normalizeVNode(vnode);
				}
				handleComponentVNode(vnode);

import { options } from 'preact';

const classNameDescriptor = {
  enumerable: false,
  configurable: true,
  get () {
    return this.class;
  },
  set (value) {
    this.class = value;
  }
};

const old = options.vnode;
options.vnode = vnode => {
  const a = vnode.attributes;
  if (a != null) {
    if ('className' in a) {
      a.class = a.className;
    }
    if ('class' in a) {
      Object.defineProperty(a, 'className', classNameDescriptor);
    }
  }
  if (old != null) old(vnode);
};

import {
	options,
	createElement,
	cloneElement,
	Component as CevicheComponent,
	render
} from 'preact';

options.vnode = vnode => {
	vnode.nodeName = vnode.type;
	vnode.attributes = vnode.props;
	vnode.children = vnode._children || [].concat(vnode.props.children || []);
};

function asArray(arr) {
	return Array.isArray(arr) ? arr : [arr];
}

function normalize(obj) {
	if (Array.isArray(obj)) {
		return obj.map(normalize);
	}
	if ('type' in obj && !('attributes' in obj)) {
		obj.attributes = obj.props;
	}