fix multiselect combobox

go/wasmruntime/reconcile.go

@@ -163,7 +163,7 @@ func createDOM(n *vdom.VNode, ns string) js.Value {
 		el.Call("setAttribute", k, v)
 	}
 	for k, v := range n.Props {
-		el.Set(k, v)
+		setProp(el, k, v)
 	}
 	for name, h := range n.Events {
 		addListener(n, name, h)
@@ -316,12 +316,33 @@ func updateAttrs(o, x *vdom.VNode) {
 func updateProps(o, x *vdom.VNode) {
 	dom := rt(x).dom
 	for k, v := range x.Props {
-		if o.Props[k] != v && dom.Get(k).String() != v {
-			dom.Set(k, v)
+		if o.Props[k] != v && !propEquals(dom, k, v) {
+			setProp(dom, k, v)
 		}
 	}
 }
 
+// setProp writes a live DOM property. Props travel as strings, but the property they
+// land on may be a boolean — and JS reads the string "false" as TRUE, so writing
+// el.checked = "false" ticks the box. Boolean props are converted before the write.
+func setProp(el js.Value, k, v string) {
+	if vdom.IsBoolProp(k) {
+		el.Set(k, v == "true")
+		return
+	}
+	el.Set(k, v)
+}
+
+// propEquals compares against what the DOM currently holds, in the property's own
+// type. It is what lets a re-render skip touching an <input> the user is typing in.
+func propEquals(el js.Value, k, v string) bool {
+	cur := el.Get(k)
+	if vdom.IsBoolProp(k) {
+		return cur.Truthy() == (v == "true")
+	}
+	return cur.String() == v
+}
+
 func updateEvents(o, x *vdom.VNode) {
 	r := rt(x) // same nodeRT as o (adopted above)
 	for name, fn := range r.jsFuncs {
@@ -441,7 +462,7 @@ func hydrateNode(dom js.Value, n *vdom.VNode) {
 		}
 	}
 	for k, v := range n.Props {
-		dom.Set(k, v)
+		setProp(dom, k, v)
 	}
 	if n.HTML != "" {
 		return // trust server-rendered HTML