src/model/documentfragment.js
/**
* @license Copyright (c) 2003-2020, CKSource - Frederico Knabben. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-oss-license
*/
/**
* @module module:engine/model/documentfragment
*/
import NodeList from './nodelist';
import Element from './element';
import Text from './text';
import TextProxy from './textproxy';
import isIterable from '@ckeditor/ckeditor5-utils/src/isiterable';
// @if CK_DEBUG_ENGINE // const { stringifyMap } = require( '../dev-utils/utils' );
/**
* DocumentFragment represents a part of model which does not have a common root but it's top-level nodes
* can be seen as siblings. In other words, it is a detached part of model tree, without a root.
*
* DocumentFragment has own {@link module:engine/model/markercollection~MarkerCollection}. Markers from this collection
* will be set to the {@link module:engine/model/model~Model#markers model markers} by a
* {@link module:engine/model/writer~Writer#insert} function.
*/
export default class DocumentFragment {
/**
* Creates an empty `DocumentFragment`.
*
* **Note:** Constructor of this class shouldn't be used directly in the code.
* Use the {@link module:engine/model/writer~Writer#createDocumentFragment} method instead.
*
* @protected
* @param {module:engine/model/node~Node|Iterable.<module:engine/model/node~Node>} [children]
* Nodes to be contained inside the `DocumentFragment`.
*/
constructor( children ) {
/**
* DocumentFragment static markers map. This is a list of names and {@link module:engine/model/range~Range ranges}
* which will be set as Markers to {@link module:engine/model/model~Model#markers model markers collection}
* when DocumentFragment will be inserted to the document.
*
* @readonly
* @member {Map<String,module:engine/model/range~Range>} module:engine/model/documentfragment~DocumentFragment#markers
*/
this.markers = new Map();
/**
* List of nodes contained inside the document fragment.
*
* @private
* @member {module:engine/model/nodelist~NodeList} module:engine/model/documentfragment~DocumentFragment#_children
*/
this._children = new NodeList();
if ( children ) {
this._insertChild( 0, children );
}
}
/**
* Returns an iterator that iterates over all nodes contained inside this document fragment.
*
* @returns {Iterable.<module:engine/model/node~Node>}
*/
[ Symbol.iterator ]() {
return this.getChildren();
}
/**
* Number of this document fragment's children.
*
* @readonly
* @type {Number}
*/
get childCount() {
return this._children.length;
}
/**
* Sum of {@link module:engine/model/node~Node#offsetSize offset sizes} of all of this document fragment's children.
*
* @readonly
* @type {Number}
*/
get maxOffset() {
return this._children.maxOffset;
}
/**
* Is `true` if there are no nodes inside this document fragment, `false` otherwise.
*
* @readonly
* @type {Boolean}
*/
get isEmpty() {
return this.childCount === 0;
}
/**
* Artificial root of `DocumentFragment`. Returns itself. Added for compatibility reasons.
*
* @readonly
* @type {module:engine/model/documentfragment~DocumentFragment}
*/
get root() {
return this;
}
/**
* Artificial parent of `DocumentFragment`. Returns `null`. Added for compatibility reasons.
*
* @readonly
* @type {null}
*/
get parent() {
return null;
}
/**
* Checks whether this object is of the given type.
*
* docFrag.is( 'documentFragment' ); // -> true
* docFrag.is( 'model:documentFragment' ); // -> true
*
* docFrag.is( 'view:documentFragment' ); // -> false
* docFrag.is( 'element' ); // -> false
* docFrag.is( 'node' ); // -> false
*
* {@link module:engine/model/node~Node#is Check the entire list of model objects} which implement the `is()` method.
*
* @param {String} type
* @returns {Boolean}
*/
is( type ) {
return type === 'documentFragment' || type === 'model:documentFragment';
}
/**
* Gets the child at the given index. Returns `null` if incorrect index was passed.
*
* @param {Number} index Index of child.
* @returns {module:engine/model/node~Node|null} Child node.
*/
getChild( index ) {
return this._children.getNode( index );
}
/**
* Returns an iterator that iterates over all of this document fragment's children.
*
* @returns {Iterable.<module:engine/model/node~Node>}
*/
getChildren() {
return this._children[ Symbol.iterator ]();
}
/**
* Returns an index of the given child node. Returns `null` if given node is not a child of this document fragment.
*
* @param {module:engine/model/node~Node} node Child node to look for.
* @returns {Number|null} Child node's index.
*/
getChildIndex( node ) {
return this._children.getNodeIndex( node );
}
/**
* Returns the starting offset of given child. Starting offset is equal to the sum of
* {@link module:engine/model/node~Node#offsetSize offset sizes} of all node's siblings that are before it. Returns `null` if
* given node is not a child of this document fragment.
*
* @param {module:engine/model/node~Node} node Child node to look for.
* @returns {Number|null} Child node's starting offset.
*/
getChildStartOffset( node ) {
return this._children.getNodeStartOffset( node );
}
/**
* Returns path to a `DocumentFragment`, which is an empty array. Added for compatibility reasons.
*
* @returns {Array}
*/
getPath() {
return [];
}
/**
* Returns a descendant node by its path relative to this element.
*
* // <this>a<b>c</b></this>
* this.getNodeByPath( [ 0 ] ); // -> "a"
* this.getNodeByPath( [ 1 ] ); // -> <b>
* this.getNodeByPath( [ 1, 0 ] ); // -> "c"
*
* @param {Array.<Number>} relativePath Path of the node to find, relative to this element.
* @returns {module:engine/model/node~Node|module:engine/model/documentfragment~DocumentFragment}
*/
getNodeByPath( relativePath ) {
let node = this; // eslint-disable-line consistent-this
for ( const index of relativePath ) {
node = node.getChild( node.offsetToIndex( index ) );
}
return node;
}
/**
* Converts offset "position" to index "position".
*
* Returns index of a node that occupies given offset. If given offset is too low, returns `0`. If given offset is
* too high, returns index after last child}.
*
* const textNode = new Text( 'foo' );
* const pElement = new Element( 'p' );
* const docFrag = new DocumentFragment( [ textNode, pElement ] );
* docFrag.offsetToIndex( -1 ); // Returns 0, because offset is too low.
* docFrag.offsetToIndex( 0 ); // Returns 0, because offset 0 is taken by `textNode` which is at index 0.
* docFrag.offsetToIndex( 1 ); // Returns 0, because `textNode` has `offsetSize` equal to 3, so it occupies offset 1 too.
* docFrag.offsetToIndex( 2 ); // Returns 0.
* docFrag.offsetToIndex( 3 ); // Returns 1.
* docFrag.offsetToIndex( 4 ); // Returns 2. There are no nodes at offset 4, so last available index is returned.
*
* @param {Number} offset Offset to look for.
* @returns {Number} Index of a node that occupies given offset.
*/
offsetToIndex( offset ) {
return this._children.offsetToIndex( offset );
}
/**
* Converts `DocumentFragment` instance to plain object and returns it.
* Takes care of converting all of this document fragment's children.
*
* @returns {Object} `DocumentFragment` instance converted to plain object.
*/
toJSON() {
const json = [];
for ( const node of this._children ) {
json.push( node.toJSON() );
}
return json;
}
/**
* Creates a `DocumentFragment` instance from given plain object (i.e. parsed JSON string).
* Converts `DocumentFragment` children to proper nodes.
*
* @param {Object} json Plain object to be converted to `DocumentFragment`.
* @returns {module:engine/model/documentfragment~DocumentFragment} `DocumentFragment` instance created using given plain object.
*/
static fromJSON( json ) {
const children = [];
for ( const child of json ) {
if ( child.name ) {
// If child has name property, it is an Element.
children.push( Element.fromJSON( child ) );
} else {
// Otherwise, it is a Text node.
children.push( Text.fromJSON( child ) );
}
}
return new DocumentFragment( children );
}
/**
* {@link #_insertChild Inserts} one or more nodes at the end of this document fragment.
*
* @protected
* @param {module:engine/model/item~Item|Iterable.<module:engine/model/item~Item>} items Items to be inserted.
*/
_appendChild( items ) {
this._insertChild( this.childCount, items );
}
/**
* Inserts one or more nodes at the given index and sets {@link module:engine/model/node~Node#parent parent} of these nodes
* to this document fragment.
*
* @protected
* @param {Number} index Index at which nodes should be inserted.
* @param {module:engine/model/item~Item|Iterable.<module:engine/model/item~Item>} items Items to be inserted.
*/
_insertChild( index, items ) {
const nodes = normalize( items );
for ( const node of nodes ) {
// If node that is being added to this element is already inside another element, first remove it from the old parent.
if ( node.parent !== null ) {
node._remove();
}
node.parent = this;
}
this._children._insertNodes( index, nodes );
}
/**
* Removes one or more nodes starting at the given index
* and sets {@link module:engine/model/node~Node#parent parent} of these nodes to `null`.
*
* @protected
* @param {Number} index Index of the first node to remove.
* @param {Number} [howMany=1] Number of nodes to remove.
* @returns {Array.<module:engine/model/node~Node>} Array containing removed nodes.
*/
_removeChildren( index, howMany = 1 ) {
const nodes = this._children._removeNodes( index, howMany );
for ( const node of nodes ) {
node.parent = null;
}
return nodes;
}
// @if CK_DEBUG_ENGINE // toString() {
// @if CK_DEBUG_ENGINE // return 'documentFragment';
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // log() {
// @if CK_DEBUG_ENGINE // console.log( 'ModelDocumentFragment: ' + this );
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // printTree() {
// @if CK_DEBUG_ENGINE // let string = 'ModelDocumentFragment: [';
// @if CK_DEBUG_ENGINE // for ( const child of this.getChildren() ) {
// @if CK_DEBUG_ENGINE // string += '\n';
// @if CK_DEBUG_ENGINE // if ( child.is( 'text' ) ) {
// @if CK_DEBUG_ENGINE // const textAttrs = stringifyMap( child._attrs );
// @if CK_DEBUG_ENGINE // string += '\t'.repeat( 1 );
// @if CK_DEBUG_ENGINE // if ( textAttrs !== '' ) {
// @if CK_DEBUG_ENGINE // string += `<$text${ textAttrs }>` + child.data + '</$text>';
// @if CK_DEBUG_ENGINE // } else {
// @if CK_DEBUG_ENGINE // string += child.data;
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // } else {
// @if CK_DEBUG_ENGINE // string += child.printTree( 1 );
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // string += '\n]';
// @if CK_DEBUG_ENGINE // return string;
// @if CK_DEBUG_ENGINE // }
// @if CK_DEBUG_ENGINE // logTree() {
// @if CK_DEBUG_ENGINE // console.log( this.printTree() );
// @if CK_DEBUG_ENGINE // }
}
// Converts strings to Text and non-iterables to arrays.
//
// @param {String|module:engine/model/item~Item|Iterable.<module:engine/model/item~Item>}
// @returns {Iterable.<module:engine/model/node~Node>}
function normalize( nodes ) {
// Separate condition because string is iterable.
if ( typeof nodes == 'string' ) {
return [ new Text( nodes ) ];
}
if ( !isIterable( nodes ) ) {
nodes = [ nodes ];
}
// Array.from to enable .map() on non-arrays.
return Array.from( nodes )
.map( node => {
if ( typeof node == 'string' ) {
return new Text( node );
}
if ( node instanceof TextProxy ) {
return new Text( node.data, node.getAttributes() );
}
return node;
} );
}