isVoidElement function
Returns true if this tag name is a void element. This method is useful to a pretty printer, because void elements must not have an end tag. See also: dev.w3.org/html5/markup/syntax.html#void-elements.
Implementation
bool isVoidElement(String? tagName) {
switch (tagName) {
case 'area':
case 'base':
case 'br':
case 'col':
case 'command':
case 'embed':
case 'hr':
case 'img':
case 'input':
case 'keygen':
case 'link':
case 'meta':
case 'param':
case 'source':
case 'track':
case 'wbr':
return true;
}
return false;
}