mediawiki-extensions-Discus.../modules/utils.js
Bartosz Dziewoński 8f583a23be Use the faster childIndexOf() approach in JS too
I was wondering if the different approach to childIndexOf()
implemented in PHP in b8d7a75c34 would
be faster in JS as well, and yes, it is.

Our test suite now takes (on my machine):
* Chrome: 8337 ms → 7355 ms (average over 5 tries)
* Firefox: 5321 ms → 5044 ms (average over 5 tries)

Change-Id: I71963eeb92dcea9bfd59cbf01a7aa0b7de5d9cf1
2020-05-22 19:33:35 +02:00

69 lines
1.5 KiB
JavaScript

'use strict';
/**
* Return a native Range object corresponding to our comment's range.
*
* @param {Object} comment
* @return {Range}
*/
function getNativeRange( comment ) {
var
doc = comment.range.startContainer.ownerDocument,
nativeRange = doc.createRange();
nativeRange.setStart( comment.range.startContainer, comment.range.startOffset );
nativeRange.setEnd( comment.range.endContainer, comment.range.endOffset );
return nativeRange;
}
/**
* Get the index of a node in its parentNode's childNode list
*
* @param {Node} child
* @return {number} Index in parentNode's childNode list
*/
function childIndexOf( child ) {
var i = 0;
while ( ( child = child.previousSibling ) ) {
i++;
}
return i;
}
/**
* Find closest ancestor element using one of the given tag names.
*
* @param {Node} node
* @param {string[]} tagNames
* @return {HTMLElement|null}
*/
function closestElement( node, tagNames ) {
do {
if (
node.nodeType === Node.ELEMENT_NODE &&
tagNames.indexOf( node.tagName.toLowerCase() ) !== -1
) {
return node;
}
node = node.parentNode;
} while ( node );
return null;
}
/**
* Trim ASCII whitespace, as defined in the HTML spec.
*
* @param {string} str
* @return {string}
*/
function htmlTrim( str ) {
// https://infra.spec.whatwg.org/#ascii-whitespace
return str.replace( /^[\t\n\f\r ]+/, '' ).replace( /[\t\n\f\r ]+$/, '' );
}
module.exports = {
getNativeRange: getNativeRange,
childIndexOf: childIndexOf,
closestElement: closestElement,
htmlTrim: htmlTrim
};