Some byte improvements (#4321)

* save bytes during event registration

* test performance improvement (does increase bytes)

* optimize undefined setting

* minor saving

* undo perf to see byte impact

Author: JoviDeCroock

src/component.js

@@ -123,21 +123,20 @@ export function getDomSibling(vnode, childIndex) {
 function renderComponent(component) {
 	let oldVNode = component._vnode,
 		oldDom = oldVNode._dom,
-		parentDom = component._parentDom,
 		commitQueue = [],
 		refQueue = [];
 
-	if (parentDom) {
+	if (component._parentDom) {
 		const newVNode = assign({}, oldVNode);
 		newVNode._original = oldVNode._original + 1;
 		if (options.vnode) options.vnode(newVNode);
 
 		diff(
-			parentDom,
+			component._parentDom,
 			newVNode,
 			oldVNode,
 			component._globalContext,
-			parentDom.ownerSVGElement !== undefined,
+			component._parentDom.ownerSVGElement !== undefined,
 			oldVNode._flags & MODE_HYDRATE ? [oldDom] : null,
 			commitQueue,
 			oldDom == null ? getDomSibling(oldVNode) : oldDom,

src/diff/index.js

@@ -579,7 +579,6 @@ export function unmount(vnode, parentVNode, skipRemove) {
 		}
 
 		r.base = r._parentDom = null;
-		vnode._component = undefined;
 	}
 
 	if ((r = vnode._children)) {
@@ -588,7 +587,7 @@ export function unmount(vnode, parentVNode, skipRemove) {
 				unmount(
 					r[i],
 					parentVNode,
-					skipRemove || typeof vnode.type !== 'function'
+					skipRemove || typeof vnode.type != 'function'
 				);
 			}
 		}
@@ -600,7 +599,7 @@ export function unmount(vnode, parentVNode, skipRemove) {
 
 	// Must be set to `undefined` to properly clean up `_nextDom`
 	// for which `null` is a valid value. See comment in `create-element.js`
-	vnode._parent = vnode._dom = vnode._nextDom = undefined;
+	vnode._component = vnode._parent = vnode._dom = vnode._nextDom = undefined;
 }
 
 /** The `.render()` method for a PFC backing instance. */

src/diff/props.js

@@ -82,15 +82,20 @@ export function setProperty(dom, name, value, oldValue, isSvg) {
 		if (value) {
 			if (!oldValue) {
 				value._attached = eventClock;
-
-				const handler = useCapture ? eventProxyCapture : eventProxy;
-				dom.addEventListener(name, handler, useCapture);
+				dom.addEventListener(
+          name,
+          useCapture ? eventProxyCapture : eventProxy,
+          useCapture
+        );
 			} else {
 				value._attached = oldValue._attached;
 			}
 		} else {
-			const handler = useCapture ? eventProxyCapture : eventProxy;
-			dom.removeEventListener(name, handler, useCapture);
+			dom.removeEventListener(
+				name,
+				useCapture ? eventProxyCapture : eventProxy,
+				useCapture
+			);
 		}
 	} else {
 		if (isSvg) {
@@ -99,18 +104,18 @@ export function setProperty(dom, name, value, oldValue, isSvg) {
 			// - className --> class
 			name = name.replace(/xlink(H|:h)/, 'h').replace(/sName$/, 's');
 		} else if (
-			name !== 'width' &&
-			name !== 'height' &&
-			name !== 'href' &&
-			name !== 'list' &&
-			name !== 'form' &&
+			name != 'width' &&
+			name != 'height' &&
+			name != 'href' &&
+			name != 'list' &&
+			name != 'form' &&
 			// Default value in browsers is `-1` and an empty string is
 			// cast to `0` instead
-			name !== 'tabIndex' &&
-			name !== 'download' &&
-			name !== 'rowSpan' &&
-			name !== 'colSpan' &&
-			name !== 'role' &&
+			name != 'tabIndex' &&
+			name != 'download' &&
+			name != 'rowSpan' &&
+			name != 'colSpan' &&
+			name != 'role' &&
 			name in dom
 		) {
 			try {