innerTextで要素を取得する方法

function findByTextContent(needle, haystack, precise) {
  // needle: String, the string to be found within the elements.
  // haystack: String, a selector to be passed to document.querySelectorAll(),
  //           NodeList, Array - to be iterated over within the function:
  // precise: Boolean, true - searches for that precise string, surrounded by
  //                          word-breaks,
  //                   false - searches for the string occurring anywhere
  var elems;

  // no haystack we quit here, to avoid having to search
  // the entire document:
  if (!haystack) {
    return false;
  }
  // if haystack is a string, we pass it to document.querySelectorAll(),
  // and turn the results into an Array:
  else if ('string' == typeof haystack) {
    elems = [].slice.call(document.querySelectorAll(haystack), 0);
  }
  // if haystack has a length property, we convert it to an Array
  // (if it's already an array, this is pointless, but not harmful):
  else if (haystack.length) {
    elems = [].slice.call(haystack, 0);
  }

  // work out whether we're looking at innerText (IE), or textContent 
  // (in most other browsers)
  var textProp = 'textContent' in document ? 'textContent' : 'innerText',
    // creating a regex depending on whether we want a precise match, or not:
    reg = precise === true ? new RegExp('\\b' + needle + '\\b') : new RegExp(needle),
    // iterating over the elems array:
    found = elems.filter(function(el) {
      // returning the elements in which the text is, or includes,
      // the needle to be found:
      return reg.test(el[textProp]);
    });
  return found.length ? found : false;;
}


findByTextContent('link', document.querySelectorAll('li'), false).forEach(function(elem) {
  elem.style.fontSize = '2em';
});

findByTextContent('link3', 'a').forEach(function(elem) {
  elem.style.color = '#f90';
});

<ul>
  <li><a href="#">link1</a>
  </li>
  <li><a href="#">link2</a>
  </li>
  <li><a href="#">link3</a>
  </li>
  <li><a href="#">link4</a>
  </li>
  <li><a href="#">link5</a>
  </li>
</ul>

var textProp = 'textContent' in document ? 'textContent' : 'innerText';

// directly converting the found 'a' elements into an Array,
// then iterating over that array with Array.prototype.forEach():
[].slice.call(document.querySelectorAll('a'), 0).forEach(function(aEl) {
  // if the text of the aEl Node contains the text 'link1':
  if (aEl[textProp].indexOf('link1') > -1) {
    // we update its style:
    aEl.style.fontSize = '2em';
    aEl.style.color = '#f90';
  }
});

<ul>
  <li><a href="#">link1</a>
  </li>
  <li><a href="#">link2</a>
  </li>
  <li><a href="#">link3</a>
  </li>
  <li><a href="#">link4</a>
  </li>
  <li><a href="#">link5</a>
  </li>
</ul>

const findNodeByContent = (text, root = document.body) => {
  const treeWalker = document.createTreeWalker(root, NodeFilter.SHOW_TEXT);

  const nodeList = [];

  while (treeWalker.nextNode()) {
    const node = treeWalker.currentNode;

    if (node.nodeType === Node.TEXT_NODE && node.textContent.includes(text)) {
      nodeList.push(node.parentNode);
    }
  };

  return nodeList;
}

const result = findNodeByContent('SearchingText');

console.log(result);

<a ...>SearchingText</a>

HTMLElement.prototype.getElementsByInnerText = function (text, escape) {
    var nodes  = this.querySelectorAll("*");
    var matches = [];
    for (var i = 0; i < nodes.length; i++) {
        if (nodes[i].innerText == text) {
            matches.push(nodes[i]);
        }
    }
    if (escape) {
        return matches;
    }
    var result = [];
    for (var i = 0; i < matches.length; i++) {
        var filter = matches[i].getElementsByInnerText(text, true);
        if (filter.length == 0) {
            result.push(matches[i]);
        }
    }
    return result;
};
document.getElementsByInnerText = HTMLElement.prototype.getElementsByInnerText;

HTMLElement.prototype.getElementByInnerText = function (text) {
    var result = this.getElementsByInnerText(text);
    if (result.length == 0) return null;
    return result[0];
}
document.getElementByInnerText = HTMLElement.prototype.getElementByInnerText;

console.log(document.getElementsByInnerText("Text1"));
console.log(document.getElementsByInnerText("Text2"));
console.log(document.getElementsByInnerText("Text4"));
console.log(document.getElementsByInnerText("Text6"));

console.log(document.getElementByInnerText("Text1"));
console.log(document.getElementByInnerText("Text2"));
console.log(document.getElementByInnerText("Text4"));
console.log(document.getElementByInnerText("Text6"));

<table>
    <tr>
        <td>Text1</td>
    </tr>
    <tr>
        <td>Text2</td>
    </tr>
    <tr>
        <td>
            <a href="#">Text2</a>
        </td>
    </tr>
    <tr>
        <td>
            <a href="#"><span>Text3</span></a>
        </td>
    </tr>
    <tr>
        <td>
            <a href="#">Special <span>Text4</span></a>
        </td>
    </tr>
    <tr>
        <td>
            Text5
            <a href="#">Text6</a>
            Text7
        </td>
    </tr>
</table>