# all files / src/js/base/core/ dom.js

89.65% Statements 329/367
84.39% Branches 200/237
91.67% Functions 66/72
89.64% Lines 320/357

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     import $ from 'jquery';
    import func from './func';
    import lists from './lists';
    import env from './env';

    const NBSP_CHAR = String.fromCharCode(160);
    const ZERO_WIDTH_NBSP_CHAR = '\ufeff';

    /**
     * @method isEditable
     *
     * returns whether node is `note-editable` or not.
     *
     * @param {Node} node
     * @return {Boolean}
     */
    function isEditable(node) {
      return node && $(node).hasClass('note-editable');
    }

    /**
     * @method isControlSizing
     *
     * returns whether node is `note-control-sizing` or not.
     *
     * @param {Node} node
     * @return {Boolean}
     */
    function isControlSizing(node) {
      return node && $(node).hasClass('note-control-sizing');
    }

    /**
     * @method makePredByNodeName
     *
     * returns predicate which judge whether nodeName is same
     *
     * @param {String} nodeName
     * @return {Function}
     */
    function makePredByNodeName(nodeName) {
      nodeName = nodeName.toUpperCase();
      return function(node) {
        return node && node.nodeName.toUpperCase() === nodeName;
      };
    }

    /**
     * @method isText
     *
     *
     *
     * @param {Node} node
     * @return {Boolean} true if node's type is text(3)
     */
    function isText(node) {
      return node && node.nodeType === 3;
    }

    /**
     * @method isElement
     *
     *
     *
     * @param {Node} node
     * @return {Boolean} true if node's type is element(1)
     */
    function isElement(node) {
      return node && node.nodeType === 1;
    }

    /**
     * ex) br, col, embed, hr, img, input, ...
     * @see http://www.w3.org/html/wg/drafts/html/master/syntax.html#void-elements
     */
    function isVoid(node) {
      return node && /^BR|^IMG|^HR|^IFRAME|^BUTTON|^INPUT/.test(node.nodeName.toUpperCase());
    }

    function isPara(node) {
      if (isEditable(node)) {
        return false;
      }

      // Chrome(v31.0), FF(v25.0.1) use DIV for paragraph
      return node && /^DIV|^P|^LI|^H[1-7]/.test(node.nodeName.toUpperCase());
    }

    function isHeading(node) {
      return node && /^H[1-7]/.test(node.nodeName.toUpperCase());
    }

    const isPre = makePredByNodeName('PRE');

    const isLi = makePredByNodeName('LI');

    function isPurePara(node) {
      return isPara(node) && !isLi(node);
    }

    const isTable = makePredByNodeName('TABLE');

    const isData = makePredByNodeName('DATA');

    function isInline(node) {
      return !isBodyContainer(node) &&
             !isList(node) &&
             !isHr(node) &&
             !isPara(node) &&
             !isTable(node) &&
             !isBlockquote(node) &&
             !isData(node);
    }

    function isList(node) {
      return node && /^UL|^OL/.test(node.nodeName.toUpperCase());
    }

    const isHr = makePredByNodeName('HR');

    function isCell(node) {
      return node && /^TD|^TH/.test(node.nodeName.toUpperCase());
    }

    const isBlockquote = makePredByNodeName('BLOCKQUOTE');

    function isBodyContainer(node) {
      return isCell(node) || isBlockquote(node) || isEditable(node);
    }

    const isAnchor = makePredByNodeName('A');

    function isParaInline(node) {
      return isInline(node) && !!ancestor(node, isPara);
    }

    function isBodyInline(node) {
      return isInline(node) && !ancestor(node, isPara);
    }

    const isBody = makePredByNodeName('BODY');

    /**
     * returns whether nodeB is closest sibling of nodeA
     *
     * @param {Node} nodeA
     * @param {Node} nodeB
     * @return {Boolean}
     */
    function isClosestSibling(nodeA, nodeB) {
      return nodeA.nextSibling === nodeB ||
             nodeA.previousSibling === nodeB;
    }

    /**
     * returns array of closest siblings with node
     *
     * @param {Node} node
     * @param {function} [pred] - predicate function
     * @return {Node[]}
     */
    function withClosestSiblings(node, pred) {
      pred = pred || func.ok;

      const siblings = [];
      Iif (node.previousSibling && pred(node.previousSibling)) {
        siblings.push(node.previousSibling);
      }
      siblings.push(node);
      if (node.nextSibling && pred(node.nextSibling)) {
        siblings.push(node.nextSibling);
      }
      return siblings;
    }

    /**
     * blank HTML for cursor position
     * - [workaround] old IE only works with &nbsp;
     * - [workaround] IE11 and other browser works with bogus br
     */
    const blankHTML = env.isMSIE && env.browserVersion < 11 ? '&nbsp;' : '<br>';

    /**
     * @method nodeLength
     *
     * returns #text's text size or element's childNodes size
     *
     * @param {Node} node
     */
    function nodeLength(node) {
      if (isText(node)) {
        return node.nodeValue.length;
      }

      Eif (node) {
        return node.childNodes.length;
      }

      return 0;
    }

    /**
     * returns whether node is empty or not.
     *
     * @param {Node} node
     * @return {Boolean}
     */
    function isEmpty(node) {
      const len = nodeLength(node);

      if (len === 0) {
        return true;
      } else if (!isText(node) && len === 1 && node.innerHTML === blankHTML) {
        // ex) <p><br></p>, <span><br></span>
        return true;
      } else Iif (lists.all(node.childNodes, isText) && node.innerHTML === '') {
        // ex) <p></p>, <span></span>
        return true;
      }

      return false;
    }

    /**
     * padding blankHTML if node is empty (for cursor position)
     */
    function paddingBlankHTML(node) {
      if (!isVoid(node) && !nodeLength(node)) {
        node.innerHTML = blankHTML;
      }
    }

    /**
     * find nearest ancestor predicate hit
     *
     * @param {Node} node
     * @param {Function} pred - predicate function
     */
    function ancestor(node, pred) {
      while (node) {
        if (pred(node)) { return node; }
        if (isEditable(node)) { break; }

        node = node.parentNode;
      }
      return null;
    }

    /**
     * find nearest ancestor only single child blood line and predicate hit
     *
     * @param {Node} node
     * @param {Function} pred - predicate function
     */
    function singleChildAncestor(node, pred) {
      node = node.parentNode;

      while (node) {
        if (nodeLength(node) !== 1) { break; }
        if (pred(node)) { return node; }
        if (isEditable(node)) { break; }

        node = node.parentNode;
      }
      return null;
    }

    /**
     * returns new array of ancestor nodes (until predicate hit).
     *
     * @param {Node} node
     * @param {Function} [optional] pred - predicate function
     */
    function listAncestor(node, pred) {
      pred = pred || func.fail;

      const ancestors = [];
      ancestor(node, function(el) {
        if (!isEditable(el)) {
          ancestors.push(el);
        }

        return pred(el);
      });
      return ancestors;
    }

    /**
     * find farthest ancestor predicate hit
     */
    function lastAncestor(node, pred) {
      const ancestors = listAncestor(node);
      return lists.last(ancestors.filter(pred));
    }

    /**
     * returns common ancestor node between two nodes.
     *
     * @param {Node} nodeA
     * @param {Node} nodeB
     */
    function commonAncestor(nodeA, nodeB) {
      const ancestors = listAncestor(nodeA);
      for (let n = nodeB; n; n = n.parentNode) {
        if ($.inArray(n, ancestors) > -1) { return n; }
      }
      return null; // difference document area
    }

    /**
     * listing all previous siblings (until predicate hit).
     *
     * @param {Node} node
     * @param {Function} [optional] pred - predicate function
     */
    function listPrev(node, pred) {
      pred = pred || func.fail;

      const nodes = [];
      while (node) {
        if (pred(node)) { break; }
        nodes.push(node);
        node = node.previousSibling;
      }
      return nodes;
    }

    /**
     * listing next siblings (until predicate hit).
     *
     * @param {Node} node
     * @param {Function} [pred] - predicate function
     */
    function listNext(node, pred) {
      pred = pred || func.fail;

      const nodes = [];
      while (node) {
        if (pred(node)) { break; }
        nodes.push(node);
        node = node.nextSibling;
      }
      return nodes;
    }

    /**
     * listing descendant nodes
     *
     * @param {Node} node
     * @param {Function} [pred] - predicate function
     */
    function listDescendant(node, pred) {
      const descendants = [];
      pred = pred || func.ok;

      // start DFS(depth first search) with node
      (function fnWalk(current) {
        if (node !== current && pred(current)) {
          descendants.push(current);
        }
        for (let idx = 0, len = current.childNodes.length; idx < len; idx++) {
          fnWalk(current.childNodes[idx]);
        }
      })(node);

      return descendants;
    }

    /**
     * wrap node with new tag.
     *
     * @param {Node} node
     * @param {Node} tagName of wrapper
     * @return {Node} - wrapper
     */
    function wrap(node, wrapperName) {
      const parent = node.parentNode;
      const wrapper = $('<' + wrapperName + '>')[0];

      parent.insertBefore(wrapper, node);
      wrapper.appendChild(node);

      return wrapper;
    }

    /**
     * insert node after preceding
     *
     * @param {Node} node
     * @param {Node} preceding - predicate function
     */
    function insertAfter(node, preceding) {
      const next = preceding.nextSibling;
      let parent = preceding.parentNode;
      if (next) {
        parent.insertBefore(node, next);
      } else {
        parent.appendChild(node);
      }
      return node;
    }

    /**
     * append elements.
     *
     * @param {Node} node
     * @param {Collection} aChild
     */
    function appendChildNodes(node, aChild) {
      $.each(aChild, function(idx, child) {
        node.appendChild(child);
      });
      return node;
    }

    /**
     * returns whether boundaryPoint is left edge or not.
     *
     * @param {BoundaryPoint} point
     * @return {Boolean}
     */
    function isLeftEdgePoint(point) {
      return point.offset === 0;
    }

    /**
     * returns whether boundaryPoint is right edge or not.
     *
     * @param {BoundaryPoint} point
     * @return {Boolean}
     */
    function isRightEdgePoint(point) {
      return point.offset === nodeLength(point.node);
    }

    /**
     * returns whether boundaryPoint is edge or not.
     *
     * @param {BoundaryPoint} point
     * @return {Boolean}
     */
    function isEdgePoint(point) {
      return isLeftEdgePoint(point) || isRightEdgePoint(point);
    }

    /**
     * returns whether node is left edge of ancestor or not.
     *
     * @param {Node} node
     * @param {Node} ancestor
     * @return {Boolean}
     */
    function isLeftEdgeOf(node, ancestor) {
      while (node && node !== ancestor) {
        if (position(node) !== 0) {
          return false;
        }
        node = node.parentNode;
      }

      return true;
    }

    /**
     * returns whether node is right edge of ancestor or not.
     *
     * @param {Node} node
     * @param {Node} ancestor
     * @return {Boolean}
     */
    function isRightEdgeOf(node, ancestor) {
      Iif (!ancestor) {
        return false;
      }
      while (node && node !== ancestor) {
        if (position(node) !== nodeLength(node.parentNode) - 1) {
          return false;
        }
        node = node.parentNode;
      }

      return true;
    }

    /**
     * returns whether point is left edge of ancestor or not.
     * @param {BoundaryPoint} point
     * @param {Node} ancestor
     * @return {Boolean}
     */
    function isLeftEdgePointOf(point, ancestor) {
      return isLeftEdgePoint(point) && isLeftEdgeOf(point.node, ancestor);
    }

    /**
     * returns whether point is right edge of ancestor or not.
     * @param {BoundaryPoint} point
     * @param {Node} ancestor
     * @return {Boolean}
     */
    function isRightEdgePointOf(point, ancestor) {
      return isRightEdgePoint(point) && isRightEdgeOf(point.node, ancestor);
    }

    /**
     * returns offset from parent.
     *
     * @param {Node} node
     */
    function position(node) {
      let offset = 0;
      while ((node = node.previousSibling)) {
        offset += 1;
      }
      return offset;
    }

    function hasChildren(node) {
      return !!(node && node.childNodes && node.childNodes.length);
    }

    /**
     * returns previous boundaryPoint
     *
     * @param {BoundaryPoint} point
     * @param {Boolean} isSkipInnerOffset
     * @return {BoundaryPoint}
     */
    function prevPoint(point, isSkipInnerOffset) {
      let node;
      let offset;

      if (point.offset === 0) {
        Iif (isEditable(point.node)) {
          return null;
        }

        node = point.node.parentNode;
        offset = position(point.node);
      } else if (hasChildren(point.node)) {
        node = point.node.childNodes[point.offset - 1];
        offset = nodeLength(node);
      } else {
        node = point.node;
        offset = isSkipInnerOffset ? 0 : point.offset - 1;
      }

      return {
        node: node,
        offset: offset
      };
    }

    /**
     * returns next boundaryPoint
     *
     * @param {BoundaryPoint} point
     * @param {Boolean} isSkipInnerOffset
     * @return {BoundaryPoint}
     */
    function nextPoint(point, isSkipInnerOffset) {
      let node, offset;

      if (nodeLength(point.node) === point.offset) {
        Iif (isEditable(point.node)) {
          return null;
        }

        node = point.node.parentNode;
        offset = position(point.node) + 1;
      } else if (hasChildren(point.node)) {
        node = point.node.childNodes[point.offset];
        offset = 0;
      } else {
        node = point.node;
        offset = isSkipInnerOffset ? nodeLength(point.node) : point.offset + 1;
      }

      return {
        node: node,
        offset: offset
      };
    }

    /**
     * returns whether pointA and pointB is same or not.
     *
     * @param {BoundaryPoint} pointA
     * @param {BoundaryPoint} pointB
     * @return {Boolean}
     */
    function isSamePoint(pointA, pointB) {
      return pointA.node === pointB.node && pointA.offset === pointB.offset;
    }

    /**
     * returns whether point is visible (can set cursor) or not.
     *
     * @param {BoundaryPoint} point
     * @return {Boolean}
     */
    function isVisiblePoint(point) {
      if (isText(point.node) || !hasChildren(point.node) || isEmpty(point.node)) {
        return true;
      }

      const leftNode = point.node.childNodes[point.offset - 1];
      const rightNode = point.node.childNodes[point.offset];
      if ((!leftNode || isVoid(leftNode)) && (!rightNode || isVoid(rightNode))) {
        return true;
      }

      return false;
    }

    /**
     * @method prevPointUtil
     *
     * @param {BoundaryPoint} point
     * @param {Function} pred
     * @return {BoundaryPoint}
     */
    function prevPointUntil(point, pred) {
      while (point) {
        if (pred(point)) {
          return point;
        }

        point = prevPoint(point);
      }

      return null;
    }

    /**
     * @method nextPointUntil
     *
     * @param {BoundaryPoint} point
     * @param {Function} pred
     * @return {BoundaryPoint}
     */
    function nextPointUntil(point, pred) {
      while (point) {
        if (pred(point)) {
          return point;
        }

        point = nextPoint(point);
      }

      return null;
    }

    /**
     * returns whether point has character or not.
     *
     * @param {Point} point
     * @return {Boolean}
     */
    function isCharPoint(point) {
      Iif (!isText(point.node)) {
        return false;
      }

      const ch = point.node.nodeValue.charAt(point.offset - 1);
      return ch && (ch !== ' ' && ch !== NBSP_CHAR);
    }

    /**
     * @method walkPoint
     *
     * @param {BoundaryPoint} startPoint
     * @param {BoundaryPoint} endPoint
     * @param {Function} handler
     * @param {Boolean} isSkipInnerOffset
     */
    function walkPoint(startPoint, endPoint, handler, isSkipInnerOffset) {
      let point = startPoint;

      while (point) {
        handler(point);

        if (isSamePoint(point, endPoint)) {
          break;
        }

        const isSkipOffset = isSkipInnerOffset &&
                           startPoint.node !== point.node &&
                           endPoint.node !== point.node;
        point = nextPoint(point, isSkipOffset);
      }
    }

    /**
     * @method makeOffsetPath
     *
     * return offsetPath(array of offset) from ancestor
     *
     * @param {Node} ancestor - ancestor node
     * @param {Node} node
     */
    function makeOffsetPath(ancestor, node) {
      const ancestors = listAncestor(node, func.eq(ancestor));
      return ancestors.map(position).reverse();
    }

    /**
     * @method fromOffsetPath
     *
     * return element from offsetPath(array of offset)
     *
     * @param {Node} ancestor - ancestor node
     * @param {array} offsets - offsetPath
     */
    function fromOffsetPath(ancestor, offsets) {
      let current = ancestor;
      for (let i = 0, len = offsets.length; i < len; i++) {
        Iif (current.childNodes.length <= offsets[i]) {
          current = current.childNodes[current.childNodes.length - 1];
        } else {
          current = current.childNodes[offsets[i]];
        }
      }
      return current;
    }

    /**
     * @method splitNode
     *
     * split element or #text
     *
     * @param {BoundaryPoint} point
     * @param {Object} [options]
     * @param {Boolean} [options.isSkipPaddingBlankHTML] - default: false
     * @param {Boolean} [options.isNotSplitEdgePoint] - default: false
     * @return {Node} right node of boundaryPoint
     */
    function splitNode(point, options) {
      const isSkipPaddingBlankHTML = options && options.isSkipPaddingBlankHTML;
      const isNotSplitEdgePoint = options && options.isNotSplitEdgePoint;

      // edge case
      if (isEdgePoint(point) && (isText(point.node) || isNotSplitEdgePoint)) {
        if (isLeftEdgePoint(point)) {
          return point.node;
        } else Eif (isRightEdgePoint(point)) {
          return point.node.nextSibling;
        }
      }

      // split #text
      if (isText(point.node)) {
        return point.node.splitText(point.offset);
      } else {
        const childNode = point.node.childNodes[point.offset];
        const clone = insertAfter(point.node.cloneNode(false), point.node);
        appendChildNodes(clone, listNext(childNode));

        if (!isSkipPaddingBlankHTML) {
          paddingBlankHTML(point.node);
          paddingBlankHTML(clone);
        }

        return clone;
      }
    }

    /**
     * @method splitTree
     *
     * split tree by point
     *
     * @param {Node} root - split root
     * @param {BoundaryPoint} point
     * @param {Object} [options]
     * @param {Boolean} [options.isSkipPaddingBlankHTML] - default: false
     * @param {Boolean} [options.isNotSplitEdgePoint] - default: false
     * @return {Node} right node of boundaryPoint
     */
    function splitTree(root, point, options) {
      // ex) [#text, <span>, <p>]
      const ancestors = listAncestor(point.node, func.eq(root));

      Iif (!ancestors.length) {
        return null;
      } else if (ancestors.length === 1) {
        return splitNode(point, options);
      }

      return ancestors.reduce(function(node, parent) {
        if (node === point.node) {
          node = splitNode(point, options);
        }

        return splitNode({
          node: parent,
          offset: node ? position(node) : nodeLength(parent)
        }, options);
      });
    }

    /**
     * split point
     *
     * @param {Point} point
     * @param {Boolean} isInline
     * @return {Object}
     */
    function splitPoint(point, isInline) {
      // find splitRoot, container
      //  - inline: splitRoot is a child of paragraph
      //  - block: splitRoot is a child of bodyContainer
      const pred = isInline ? isPara : isBodyContainer;
      const ancestors = listAncestor(point.node, pred);
      const topAncestor = lists.last(ancestors) || point.node;

      let splitRoot, container;
      if (pred(topAncestor)) {
        splitRoot = ancestors[ancestors.length - 2];
        container = topAncestor;
      } else {
        splitRoot = topAncestor;
        container = splitRoot.parentNode;
      }

      // if splitRoot is exists, split with splitTree
      let pivot = splitRoot && splitTree(splitRoot, point, {
        isSkipPaddingBlankHTML: isInline,
        isNotSplitEdgePoint: isInline
      });

      // if container is point.node, find pivot with point.offset
      if (!pivot && container === point.node) {
        pivot = point.node.childNodes[point.offset];
      }

      return {
        rightNode: pivot,
        container: container
      };
    }

    function create(nodeName) {
      return document.createElement(nodeName);
    }

    function createText(text) {
      return document.createTextNode(text);
    }

    /**
     * @method remove
     *
     * remove node, (isRemoveChild: remove child or not)
     *
     * @param {Node} node
     * @param {Boolean} isRemoveChild
     */
    function remove(node, isRemoveChild) {
      if (!node || !node.parentNode) { return; }
      Iif (node.removeNode) { return node.removeNode(isRemoveChild); }

      const parent = node.parentNode;
      if (!isRemoveChild) {
        const nodes = [];
        for (let i = 0, len = node.childNodes.length; i < len; i++) {
          nodes.push(node.childNodes[i]);
        }

        for (let i = 0, len = nodes.length; i < len; i++) {
          parent.insertBefore(nodes[i], node);
        }
      }

      parent.removeChild(node);
    }

    /**
     * @method removeWhile
     *
     * @param {Node} node
     * @param {Function} pred
     */
    function removeWhile(node, pred) {
      while (node) {
        if (isEditable(node) || !pred(node)) {
          break;
        }

        const parent = node.parentNode;
        remove(node);
        node = parent;
      }
    }

    /**
     * @method replace
     *
     * replace node with provided nodeName
     *
     * @param {Node} node
     * @param {String} nodeName
     * @return {Node} - new node
     */
    function replace(node, nodeName) {
      Iif (node.nodeName.toUpperCase() === nodeName.toUpperCase()) {
        return node;
      }

      const newNode = create(nodeName);

      Iif (node.style.cssText) {
        newNode.style.cssText = node.style.cssText;
      }

      appendChildNodes(newNode, lists.from(node.childNodes));
      insertAfter(newNode, node);
      remove(node);

      return newNode;
    }

    const isTextarea = makePredByNodeName('TEXTAREA');

    /**
     * @param {jQuery} $node
     * @param {Boolean} [stripLinebreaks] - default: false
     */
    function value($node, stripLinebreaks) {
      const val = isTextarea($node[0]) ? $node.val() : $node.html();
      Iif (stripLinebreaks) {
        return val.replace(/[\n\r]/g, '');
      }
      return val;
    }

    /**
     * @method html
     *
     * get the HTML contents of node
     *
     * @param {jQuery} $node
     * @param {Boolean} [isNewlineOnBlock]
     */
    function html($node, isNewlineOnBlock) {
      let markup = value($node);

      Iif (isNewlineOnBlock) {
        const regexTag = /<(\/?)(\b(?!!)[^>\s]*)(.*?)(\s*\/?>)/g;
        markup = markup.replace(regexTag, function(match, endSlash, name) {
          name = name.toUpperCase();
          const isEndOfInlineContainer = /^DIV|^TD|^TH|^P|^LI|^H[1-7]/.test(name) &&
                                       !!endSlash;
          const isBlockNode = /^BLOCKQUOTE|^TABLE|^TBODY|^TR|^HR|^UL|^OL/.test(name);

          return match + ((isEndOfInlineContainer || isBlockNode) ? '\n' : '');
        });
        markup = $.trim(markup);
      }

      return markup;
    }

    function posFromPlaceholder(placeholder) {
      const $placeholder = $(placeholder);
      const pos = $placeholder.offset();
      const height = $placeholder.outerHeight(true); // include margin

      return {
        left: pos.left,
        top: pos.top + height
      };
    }

    function attachEvents($node, events) {
      Object.keys(events).forEach(function(key) {
        $node.on(key, events[key]);
      });
    }

    function detachEvents($node, events) {
      Object.keys(events).forEach(function(key) {
        $node.off(key, events[key]);
      });
    }

    /**
     * @method isCustomStyleTag
     *
     * assert if a node contains a "note-styletag" class,
     * which implies that's a custom-made style tag node
     *
     * @param {Node} an HTML DOM node
     */
    function isCustomStyleTag(node) {
      return node && !isText(node) && lists.contains(node.classList, 'note-styletag');
    }

    export default {
      /** @property {String} NBSP_CHAR */
      NBSP_CHAR,
      /** @property {String} ZERO_WIDTH_NBSP_CHAR */
      ZERO_WIDTH_NBSP_CHAR,
      /** @property {String} blank */
      blank: blankHTML,
      /** @property {String} emptyPara */
      emptyPara: `<p>${blankHTML}</p>`,
      makePredByNodeName,
      isEditable,
      isControlSizing,
      isText,
      isElement,
      isVoid,
      isPara,
      isPurePara,
      isHeading,
      isInline,
      isBlock: func.not(isInline),
      isBodyInline,
      isBody,
      isParaInline,
      isPre,
      isList,
      isTable,
      isData,
      isCell,
      isBlockquote,
      isBodyContainer,
      isAnchor,
      isDiv: makePredByNodeName('DIV'),
      isLi,
      isBR: makePredByNodeName('BR'),
      isSpan: makePredByNodeName('SPAN'),
      isB: makePredByNodeName('B'),
      isU: makePredByNodeName('U'),
      isS: makePredByNodeName('S'),
      isI: makePredByNodeName('I'),
      isImg: makePredByNodeName('IMG'),
      isTextarea,
      isEmpty,
      isEmptyAnchor: func.and(isAnchor, isEmpty),
      isClosestSibling,
      withClosestSiblings,
      nodeLength,
      isLeftEdgePoint,
      isRightEdgePoint,
      isEdgePoint,
      isLeftEdgeOf,
      isRightEdgeOf,
      isLeftEdgePointOf,
      isRightEdgePointOf,
      prevPoint,
      nextPoint,
      isSamePoint,
      isVisiblePoint,
      prevPointUntil,
      nextPointUntil,
      isCharPoint,
      walkPoint,
      ancestor,
      singleChildAncestor,
      listAncestor,
      lastAncestor,
      listNext,
      listPrev,
      listDescendant,
      commonAncestor,
      wrap,
      insertAfter,
      appendChildNodes,
      position,
      hasChildren,
      makeOffsetPath,
      fromOffsetPath,
      splitTree,
      splitPoint,
      create,
      createText,
      remove,
      removeWhile,
      replace,
      html,
      value,
      posFromPlaceholder,
      attachEvents,
      detachEvents,
      isCustomStyleTag
    };