jrf0110/get-line-no.js

## get-line-no.js
/**
 * Gets the line number of an element in an HTML element
 * @return number -1 if not found
 * @example
 *   getLineNo(document.body)
 * @caveat
 *  This function assumes that <html>, </html>, and the DOCTYPE
 *  declaration are all on their own lines. If this isn't the case,
 *  you can adjust options.numLinesForHTMLElement. ALSO, I didn't
 *  make any concessions for browser support, but the general technique
 *  should across browsers. ALSO, this technique is totally useless if
 *  you want the ORIGINAL source line number and some other JS already
 *  messed with the DOM where the element lives
 */
function getLineNo(element, options = {}) {
  for (const key in getLineNo.defaultOptions) {
    if (!(key in options)) options[key] = getLineNo.defaultOptions[key]
  }

  const MAX_I = 100
  let prev
  let i = 0
  let curr = element

  // Get the root node for this element
  while (curr.parentElement !== null && ++i < options.maxIterationsForRoot) {
    curr = curr.parentElement
  }

  if (i === MAX_I) return -1

  // Apply a unique identifier to the element that's very unlikely to
  // have gotten here otherwise
  const id = getLineNo.uuid()
  const searchFor = `data-search-id="${id}"`
  element.dataset.searchId = id

  const lines = curr.innerHTML.split('\n')

  // Find the line containing our id
  for (let i = 0; i < lines.length; i++) {
    if (lines[i].indexOf(searchFor) > -1) {
      delete element.dataset.searchId
      return i + options.numLinesForHTMLElement
    }
  }

  delete element.dataset.searchId
  return -1
}

getLineNo.defaultOptions = {
  // This includes html open, close, and the doctype
  numLinesForHTMLElement: 3,
  // Maximum amount of times we check for parent before breaking
  // the loop to avoid possible infinite loops
  maxIterationsForRoot: 100,
}

// Credit: http://stackoverflow.com/a/2117523
getLineNo.uuid = function uuid(){
  return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
    var r = Math.random()*16|0, v = c == 'x' ? r : (r&0x3|0x8)
    return v.toString(16)
  })
}
	/**
	* Gets the line number of an element in an HTML element
	* @return number -1 if not found
	* @example
	* getLineNo(document.body)
	* @caveat
	* This function assumes that <html>, </html>, and the DOCTYPE
	* declaration are all on their own lines. If this isn't the case,
	* you can adjust options.numLinesForHTMLElement. ALSO, I didn't
	* make any concessions for browser support, but the general technique
	* should across browsers. ALSO, this technique is totally useless if
	* you want the ORIGINAL source line number and some other JS already
	* messed with the DOM where the element lives
	*/
	function getLineNo(element, options = {}) {
	for (const key in getLineNo.defaultOptions) {
	if (!(key in options)) options[key] = getLineNo.defaultOptions[key]
	}

	const MAX_I = 100
	let prev
	let i = 0
	let curr = element

	// Get the root node for this element
	while (curr.parentElement !== null && ++i < options.maxIterationsForRoot) {
	curr = curr.parentElement
	}

	if (i === MAX_I) return -1

	// Apply a unique identifier to the element that's very unlikely to
	// have gotten here otherwise
	const id = getLineNo.uuid()
	const searchFor = `data-search-id="${id}"`
	element.dataset.searchId = id

	const lines = curr.innerHTML.split('\n')

	// Find the line containing our id
	for (let i = 0; i < lines.length; i++) {
	if (lines[i].indexOf(searchFor) > -1) {
	delete element.dataset.searchId
	return i + options.numLinesForHTMLElement
	}
	}

	delete element.dataset.searchId
	return -1
	}

	getLineNo.defaultOptions = {
	// This includes html open, close, and the doctype
	numLinesForHTMLElement: 3,
	// Maximum amount of times we check for parent before breaking
	// the loop to avoid possible infinite loops
	maxIterationsForRoot: 100,
	}

	// Credit: http://stackoverflow.com/a/2117523
	getLineNo.uuid = function uuid(){
	return 'xxxxxxxx-xxxx-4xxx-yxxx-xxxxxxxxxxxx'.replace(/[xy]/g, function(c) {
	var r = Math.random()*16\|0, v = c == 'x' ? r : (r&0x3\|0x8)
	return v.toString(16)
	})
	}