@ckeditor/ckeditor5-list
Version:
Ordered and unordered lists feature to CKEditor 5.
906 lines (905 loc) • 42.1 kB
JavaScript
/**
* @license Copyright (c) 2003-2025, CKSource Holding sp. z o.o. All rights reserved.
* For licensing, see LICENSE.md or https://ckeditor.com/legal/ckeditor-licensing-options
*/
/**
* @module list/legacylist/legacyconverters
*/
import { TreeWalker } from 'ckeditor5/src/engine.js';
import { generateLiInUl, injectViewList, mergeViewLists, getSiblingListItem, positionAfterUiElements } from './legacyutils.js';
/**
* A model-to-view converter for the `listItem` model element insertion.
*
* It creates a `<ul><li></li><ul>` (or `<ol>`) view structure out of a `listItem` model element, inserts it at the correct
* position, and merges the list with surrounding lists (if available).
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:insert
* @param model Model instance.
*/
export function modelViewInsertion(model) {
return (evt, data, conversionApi) => {
const consumable = conversionApi.consumable;
if (!consumable.test(data.item, 'insert') ||
!consumable.test(data.item, 'attribute:listType') ||
!consumable.test(data.item, 'attribute:listIndent')) {
return;
}
consumable.consume(data.item, 'insert');
consumable.consume(data.item, 'attribute:listType');
consumable.consume(data.item, 'attribute:listIndent');
const modelItem = data.item;
const viewItem = generateLiInUl(modelItem, conversionApi);
injectViewList(modelItem, viewItem, conversionApi, model);
};
}
/**
* A model-to-view converter for the `listItem` model element removal.
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:remove
* @param model Model instance.
* @returns Returns a conversion callback.
*/
export function modelViewRemove(model) {
return (evt, data, conversionApi) => {
const viewPosition = conversionApi.mapper.toViewPosition(data.position);
const viewStart = viewPosition.getLastMatchingPosition(value => !value.item.is('element', 'li'));
const viewItem = viewStart.nodeAfter;
const viewWriter = conversionApi.writer;
// 1. Break the container after and before the list item.
// This will create a view list with one view list item - the one to remove.
viewWriter.breakContainer(viewWriter.createPositionBefore(viewItem));
viewWriter.breakContainer(viewWriter.createPositionAfter(viewItem));
// 2. Remove the list with the item to remove.
const viewList = viewItem.parent;
const viewListPrev = viewList.previousSibling;
const removeRange = viewWriter.createRangeOn(viewList);
const removed = viewWriter.remove(removeRange);
// 3. Merge the whole created by breaking and removing the list.
if (viewListPrev && viewListPrev.nextSibling) {
mergeViewLists(viewWriter, viewListPrev, viewListPrev.nextSibling);
}
// 4. Bring back nested list that was in the removed <li>.
const modelItem = conversionApi.mapper.toModelElement(viewItem);
hoistNestedLists(modelItem.getAttribute('listIndent') + 1, data.position, removeRange.start, viewItem, conversionApi, model);
// 5. Unbind removed view item and all children.
for (const child of viewWriter.createRangeIn(removed).getItems()) {
conversionApi.mapper.unbindViewElement(child);
}
evt.stop();
};
}
/**
* A model-to-view converter for the `type` attribute change on the `listItem` model element.
*
* This change means that the `<li>` element parent changes from `<ul>` to `<ol>` (or vice versa). This is accomplished
* by breaking view elements and changing their name. The next {@link module:list/legacylist/legacyconverters~modelViewMergeAfterChangeType}
* converter will attempt to merge split nodes.
*
* Splitting this conversion into 2 steps makes it possible to add an additional conversion in the middle.
* Check {@link module:list/legacytodolist/legacytodolistconverters~modelViewChangeType} to see an example of it.
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:attribute
*/
export const modelViewChangeType = (evt, data, conversionApi) => {
if (!conversionApi.consumable.test(data.item, evt.name)) {
return;
}
const viewItem = conversionApi.mapper.toViewElement(data.item);
const viewWriter = conversionApi.writer;
// Break the container after and before the list item.
// This will create a view list with one view list item -- the one that changed type.
viewWriter.breakContainer(viewWriter.createPositionBefore(viewItem));
viewWriter.breakContainer(viewWriter.createPositionAfter(viewItem));
// Change name of the view list that holds the changed view item.
// We cannot just change name property, because that would not render properly.
const viewList = viewItem.parent;
const listName = data.attributeNewValue == 'numbered' ? 'ol' : 'ul';
viewWriter.rename(listName, viewList);
};
/**
* A model-to-view converter that attempts to merge nodes split by {@link module:list/legacylist/legacyconverters~modelViewChangeType}.
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:attribute
*/
export const modelViewMergeAfterChangeType = (evt, data, conversionApi) => {
conversionApi.consumable.consume(data.item, evt.name);
const viewItem = conversionApi.mapper.toViewElement(data.item);
const viewList = viewItem.parent;
const viewWriter = conversionApi.writer;
// Merge the changed view list with other lists, if possible.
mergeViewLists(viewWriter, viewList, viewList.nextSibling);
mergeViewLists(viewWriter, viewList.previousSibling, viewList);
};
/**
* A model-to-view converter for the `listIndent` attribute change on the `listItem` model element.
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:attribute
* @param model Model instance.
* @returns Returns a conversion callback.
*/
export function modelViewChangeIndent(model) {
return (evt, data, conversionApi) => {
if (!conversionApi.consumable.consume(data.item, 'attribute:listIndent')) {
return;
}
const viewItem = conversionApi.mapper.toViewElement(data.item);
const viewWriter = conversionApi.writer;
// 1. Break the container after and before the list item.
// This will create a view list with one view list item -- the one that changed type.
viewWriter.breakContainer(viewWriter.createPositionBefore(viewItem));
viewWriter.breakContainer(viewWriter.createPositionAfter(viewItem));
// 2. Extract view list with changed view list item and merge "hole" possibly created by breaking and removing elements.
const viewList = viewItem.parent;
const viewListPrev = viewList.previousSibling;
const removeRange = viewWriter.createRangeOn(viewList);
viewWriter.remove(removeRange);
if (viewListPrev && viewListPrev.nextSibling) {
mergeViewLists(viewWriter, viewListPrev, viewListPrev.nextSibling);
}
// 3. Bring back nested list that was in the removed <li>.
hoistNestedLists(data.attributeOldValue + 1, data.range.start, removeRange.start, viewItem, conversionApi, model);
// 4. Inject view list like it is newly inserted.
injectViewList(data.item, viewItem, conversionApi, model);
// 5. Consume insertion of children inside the item. They are already handled by re-building the item in view.
for (const child of data.item.getChildren()) {
conversionApi.consumable.consume(child, 'insert');
}
};
}
/**
* A special model-to-view converter introduced by the {@link module:list/legacylist~LegacyList list feature}. This converter is fired for
* insert change of every model item, and should be fired before the actual converter. The converter checks whether the inserted
* model item is a non-`listItem` element. If it is, and it is inserted inside a view list, the converter breaks the
* list so the model element is inserted to the view parent element corresponding to its model parent element.
*
* The converter prevents such situations:
*
* ```xml
* // Model: // View:
* <listItem>foo</listItem> <ul>
* <listItem>bar</listItem> <li>foo</li>
* <li>bar</li>
* </ul>
*
* // After change: // Correct view guaranteed by this converter:
* <listItem>foo</listItem> <ul><li>foo</li></ul><p>xxx</p><ul><li>bar</li></ul>
* <paragraph>xxx</paragraph> // Instead of this wrong view state:
* <listItem>bar</listItem> <ul><li>foo</li><p>xxx</p><li>bar</li></ul>
* ```
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:insert
*/
export const modelViewSplitOnInsert = (evt, data, conversionApi) => {
if (!conversionApi.consumable.test(data.item, evt.name)) {
return;
}
if (data.item.name != 'listItem') {
let viewPosition = conversionApi.mapper.toViewPosition(data.range.start);
const viewWriter = conversionApi.writer;
const lists = [];
// Break multiple ULs/OLs if there are.
//
// Imagine following list:
//
// 1 --------
// 1.1 --------
// 1.1.1 --------
// 1.1.2 --------
// 1.1.3 --------
// 1.1.3.1 --------
// 1.2 --------
// 1.2.1 --------
// 2 --------
//
// Insert paragraph after item 1.1.1:
//
// 1 --------
// 1.1 --------
// 1.1.1 --------
//
// Lorem ipsum.
//
// 1.1.2 --------
// 1.1.3 --------
// 1.1.3.1 --------
// 1.2 --------
// 1.2.1 --------
// 2 --------
//
// In this case 1.1.2 has to become beginning of a new list.
// We need to break list before 1.1.2 (obvious), then we need to break list also before 1.2.
// Then we need to move those broken pieces one after another and merge:
//
// 1 --------
// 1.1 --------
// 1.1.1 --------
//
// Lorem ipsum.
//
// 1.1.2 --------
// 1.1.3 --------
// 1.1.3.1 --------
// 1.2 --------
// 1.2.1 --------
// 2 --------
//
while (viewPosition.parent.name == 'ul' || viewPosition.parent.name == 'ol') {
viewPosition = viewWriter.breakContainer(viewPosition);
if (viewPosition.parent.name != 'li') {
break;
}
// Remove lists that are after inserted element.
// They will be brought back later, below the inserted element.
const removeStart = viewPosition;
const removeEnd = viewWriter.createPositionAt(viewPosition.parent, 'end');
// Don't remove if there is nothing to remove.
if (!removeStart.isEqual(removeEnd)) {
const removed = viewWriter.remove(viewWriter.createRange(removeStart, removeEnd));
lists.push(removed);
}
viewPosition = viewWriter.createPositionAfter(viewPosition.parent);
}
// Bring back removed lists.
if (lists.length > 0) {
for (let i = 0; i < lists.length; i++) {
const previousList = viewPosition.nodeBefore;
const insertedRange = viewWriter.insert(viewPosition, lists[i]);
viewPosition = insertedRange.end;
// Don't merge first list! We want a split in that place (this is why this converter is introduced).
if (i > 0) {
const mergePos = mergeViewLists(viewWriter, previousList, previousList.nextSibling);
// If `mergePos` is in `previousList` it means that the lists got merged.
// In this case, we need to fix insert position.
if (mergePos && mergePos.parent == previousList) {
viewPosition.offset--;
}
}
}
// Merge last inserted list with element after it.
mergeViewLists(viewWriter, viewPosition.nodeBefore, viewPosition.nodeAfter);
}
}
};
/**
* A special model-to-view converter introduced by the {@link module:list/legacylist~LegacyList list feature}. This converter takes care of
* merging view lists after something is removed or moved from near them.
*
* Example:
*
* ```xml
* // Model: // View:
* <listItem>foo</listItem> <ul><li>foo</li></ul>
* <paragraph>xxx</paragraph> <p>xxx</p>
* <listItem>bar</listItem> <ul><li>bar</li></ul>
*
* // After change: // Correct view guaranteed by this converter:
* <listItem>foo</listItem> <ul>
* <listItem>bar</listItem> <li>foo</li>
* <li>bar</li>
* </ul>
* ```
*
* @see module:engine/conversion/downcastdispatcher~DowncastDispatcher#event:remove
*/
export const modelViewMergeAfter = (evt, data, conversionApi) => {
const viewPosition = conversionApi.mapper.toViewPosition(data.position);
const viewItemPrev = viewPosition.nodeBefore;
const viewItemNext = viewPosition.nodeAfter;
// Merge lists if something (remove, move) was done from inside of list.
// Merging will be done only if both items are view lists of the same type.
// The check is done inside the helper function.
mergeViewLists(conversionApi.writer, viewItemPrev, viewItemNext);
};
/**
* A view-to-model converter that converts the `<li>` view elements into the `listItem` model elements.
*
* To set correct values of the `listType` and `listIndent` attributes the converter:
* * checks `<li>`'s parent,
* * stores and increases the `conversionApi.store.indent` value when `<li>`'s sub-items are converted.
*
* @see module:engine/conversion/upcastdispatcher~UpcastDispatcher#event:element
*/
export const viewModelConverter = (evt, data, conversionApi) => {
if (conversionApi.consumable.consume(data.viewItem, { name: true })) {
const writer = conversionApi.writer;
// 1. Create `listItem` model element.
const listItem = writer.createElement('listItem');
// 2. Handle `listItem` model element attributes.
const indent = getIndent(data.viewItem);
writer.setAttribute('listIndent', indent, listItem);
// Set 'bulleted' as default. If this item is pasted into a context,
const type = data.viewItem.parent && data.viewItem.parent.name == 'ol' ? 'numbered' : 'bulleted';
writer.setAttribute('listType', type, listItem);
if (!conversionApi.safeInsert(listItem, data.modelCursor)) {
return;
}
const nextPosition = viewToModelListItemChildrenConverter(listItem, data.viewItem.getChildren(), conversionApi);
// Result range starts before the first item and ends after the last.
data.modelRange = writer.createRange(data.modelCursor, nextPosition);
conversionApi.updateConversionResult(listItem, data);
}
};
/**
* A view-to-model converter for the `<ul>` and `<ol>` view elements that cleans the input view of garbage.
* This is mostly to clean whitespaces from between the `<li>` view elements inside the view list element, however, also
* incorrect data can be cleared if the view was incorrect.
*
* @see module:engine/conversion/upcastdispatcher~UpcastDispatcher#event:element
*/
export const cleanList = (evt, data, conversionApi) => {
if (conversionApi.consumable.test(data.viewItem, { name: true })) {
// Caching children because when we start removing them iterating fails.
const children = Array.from(data.viewItem.getChildren());
for (const child of children) {
const isWrongElement = !(child.is('element', 'li') || isList(child));
if (isWrongElement) {
child._remove();
}
}
}
};
/**
* A view-to-model converter for the `<li>` elements that cleans whitespace formatting from the input view.
*
* @see module:engine/conversion/upcastdispatcher~UpcastDispatcher#event:element
*/
export const cleanListItem = (evt, data, conversionApi) => {
if (conversionApi.consumable.test(data.viewItem, { name: true })) {
if (data.viewItem.childCount === 0) {
return;
}
const children = [...data.viewItem.getChildren()];
let foundList = false;
for (const child of children) {
if (foundList && !isList(child)) {
child._remove();
}
if (isList(child)) {
// If this is a <ul> or <ol>, do not process it, just mark that we already visited list element.
foundList = true;
}
}
}
};
/**
* Returns a callback for model position to view position mapping for {@link module:engine/conversion/mapper~Mapper}. The callback fixes
* positions between the `listItem` elements that would be incorrectly mapped because of how list items are represented in the model
* and in the view.
*/
export function modelToViewPosition(view) {
return (evt, data) => {
if (data.isPhantom) {
return;
}
const modelItem = data.modelPosition.nodeBefore;
if (modelItem && modelItem.is('element', 'listItem')) {
const viewItem = data.mapper.toViewElement(modelItem);
const topmostViewList = viewItem.getAncestors().find(isList);
const walker = view.createPositionAt(viewItem, 0).getWalker();
for (const value of walker) {
if (value.type == 'elementStart' && value.item.is('element', 'li')) {
data.viewPosition = value.previousPosition;
break;
}
else if (value.type == 'elementEnd' && value.item == topmostViewList) {
data.viewPosition = value.nextPosition;
break;
}
}
}
};
}
/**
* The callback for view position to model position mapping for {@link module:engine/conversion/mapper~Mapper}. The callback fixes
* positions between the `<li>` elements that would be incorrectly mapped because of how list items are represented in the model
* and in the view.
*
* @see module:engine/conversion/mapper~Mapper#event:viewToModelPosition
* @param model Model instance.
* @returns Returns a conversion callback.
*/
export function viewToModelPosition(model) {
return (evt, data) => {
const viewPos = data.viewPosition;
const viewParent = viewPos.parent;
const mapper = data.mapper;
if (viewParent.name == 'ul' || viewParent.name == 'ol') {
// Position is directly in <ul> or <ol>.
if (!viewPos.isAtEnd) {
// If position is not at the end, it must be before <li>.
// Get that <li>, map it to `listItem` and set model position before that `listItem`.
const modelNode = mapper.toModelElement(viewPos.nodeAfter);
data.modelPosition = model.createPositionBefore(modelNode);
}
else {
// Position is at the end of <ul> or <ol>, so there is no <li> after it to be mapped.
// There is <li> before the position, but we cannot just map it to `listItem` and set model position after it,
// because that <li> may contain nested items.
// We will check "model length" of that <li>, in other words - how many `listItem`s are in that <li>.
const modelNode = mapper.toModelElement(viewPos.nodeBefore);
const modelLength = mapper.getModelLength(viewPos.nodeBefore);
// Then we get model position before mapped `listItem` and shift it accordingly.
data.modelPosition = model.createPositionBefore(modelNode).getShiftedBy(modelLength);
}
evt.stop();
}
else if (viewParent.name == 'li' &&
viewPos.nodeBefore &&
(viewPos.nodeBefore.name == 'ul' || viewPos.nodeBefore.name == 'ol')) {
// In most cases when view position is in <li> it is in text and this is a correct position.
// However, if position is after <ul> or <ol> we have to fix it -- because in model <ul>/<ol> are not in the `listItem`.
const modelNode = mapper.toModelElement(viewParent);
// Check all <ul>s and <ol>s that are in the <li> but before mapped position.
// Get model length of those elements and then add it to the offset of `listItem` mapped to the original <li>.
let modelLength = 1; // Starts from 1 because the original <li> has to be counted in too.
let viewList = viewPos.nodeBefore;
while (viewList && isList(viewList)) {
modelLength += mapper.getModelLength(viewList);
viewList = viewList.previousSibling;
}
data.modelPosition = model.createPositionBefore(modelNode).getShiftedBy(modelLength);
evt.stop();
}
};
}
/**
* Post-fixer that reacts to changes on document and fixes incorrect model states.
*
* In the example below, there is a correct list structure.
* Then the middle element is removed so the list structure will become incorrect:
*
* ```xml
* <listItem listType="bulleted" listIndent=0>Item 1</listItem>
* <listItem listType="bulleted" listIndent=1>Item 2</listItem> <--- this is removed.
* <listItem listType="bulleted" listIndent=2>Item 3</listItem>
* ```
*
* The list structure after the middle element is removed:
*
* ```xml
* <listItem listType="bulleted" listIndent=0>Item 1</listItem>
* <listItem listType="bulleted" listIndent=2>Item 3</listItem>
* ```
*
* Should become:
*
* ```xml
* <listItem listType="bulleted" listIndent=0>Item 1</listItem>
* <listItem listType="bulleted" listIndent=1>Item 3</listItem> <--- note that indent got post-fixed.
* ```
*
* @param model The data model.
* @param writer The writer to do changes with.
* @returns `true` if any change has been applied, `false` otherwise.
*/
export function modelChangePostFixer(model, writer) {
const changes = model.document.differ.getChanges();
const itemToListHead = new Map();
let applied = false;
for (const entry of changes) {
if (entry.type == 'insert' && entry.name == 'listItem') {
_addListToFix(entry.position);
}
else if (entry.type == 'insert' && entry.name != 'listItem') {
if (entry.name != '$text') {
// In case of renamed element.
const item = entry.position.nodeAfter;
if (item.hasAttribute('listIndent')) {
writer.removeAttribute('listIndent', item);
applied = true;
}
if (item.hasAttribute('listType')) {
writer.removeAttribute('listType', item);
applied = true;
}
if (item.hasAttribute('listStyle')) {
writer.removeAttribute('listStyle', item);
applied = true;
}
if (item.hasAttribute('listReversed')) {
writer.removeAttribute('listReversed', item);
applied = true;
}
if (item.hasAttribute('listStart')) {
writer.removeAttribute('listStart', item);
applied = true;
}
for (const innerItem of Array.from(model.createRangeIn(item)).filter(e => e.item.is('element', 'listItem'))) {
_addListToFix(innerItem.previousPosition);
}
}
const posAfter = entry.position.getShiftedBy(entry.length);
_addListToFix(posAfter);
}
else if (entry.type == 'remove' && entry.name == 'listItem') {
_addListToFix(entry.position);
}
else if (entry.type == 'attribute' && entry.attributeKey == 'listIndent') {
_addListToFix(entry.range.start);
}
else if (entry.type == 'attribute' && entry.attributeKey == 'listType') {
_addListToFix(entry.range.start);
}
}
for (const listHead of itemToListHead.values()) {
_fixListIndents(listHead);
_fixListTypes(listHead);
}
return applied;
function _addListToFix(position) {
const previousNode = position.nodeBefore;
if (!previousNode || !previousNode.is('element', 'listItem')) {
const item = position.nodeAfter;
if (item && item.is('element', 'listItem')) {
itemToListHead.set(item, item);
}
}
else {
let listHead = previousNode;
if (itemToListHead.has(listHead)) {
return;
}
for (
// Cache previousSibling and reuse for performance reasons. See #6581.
let previousSibling = listHead.previousSibling; previousSibling && previousSibling.is('element', 'listItem'); previousSibling = listHead.previousSibling) {
listHead = previousSibling;
if (itemToListHead.has(listHead)) {
return;
}
}
itemToListHead.set(previousNode, listHead);
}
}
function _fixListIndents(item) {
let maxIndent = 0;
let fixBy = null;
while (item && item.is('element', 'listItem')) {
const itemIndent = item.getAttribute('listIndent');
if (itemIndent > maxIndent) {
let newIndent;
if (fixBy === null) {
fixBy = itemIndent - maxIndent;
newIndent = maxIndent;
}
else {
if (fixBy > itemIndent) {
fixBy = itemIndent;
}
newIndent = itemIndent - fixBy;
}
writer.setAttribute('listIndent', newIndent, item);
applied = true;
}
else {
fixBy = null;
maxIndent = item.getAttribute('listIndent') + 1;
}
item = item.nextSibling;
}
}
function _fixListTypes(item) {
let typesStack = [];
let prev = null;
while (item && item.is('element', 'listItem')) {
const itemIndent = item.getAttribute('listIndent');
if (prev && prev.getAttribute('listIndent') > itemIndent) {
typesStack = typesStack.slice(0, itemIndent + 1);
}
if (itemIndent != 0) {
if (typesStack[itemIndent]) {
const type = typesStack[itemIndent];
if (item.getAttribute('listType') != type) {
writer.setAttribute('listType', type, item);
applied = true;
}
}
else {
typesStack[itemIndent] = item.getAttribute('listType');
}
}
prev = item;
item = item.nextSibling;
}
}
}
/**
* A fixer for pasted content that includes list items.
*
* It fixes indentation of pasted list items so the pasted items match correctly to the context they are pasted into.
*
* Example:
*
* ```xml
* <listItem listType="bulleted" listIndent=0>A</listItem>
* <listItem listType="bulleted" listIndent=1>B^</listItem>
* // At ^ paste: <listItem listType="bulleted" listIndent=4>X</listItem>
* // <listItem listType="bulleted" listIndent=5>Y</listItem>
* <listItem listType="bulleted" listIndent=2>C</listItem>
* ```
*
* Should become:
*
* ```xml
* <listItem listType="bulleted" listIndent=0>A</listItem>
* <listItem listType="bulleted" listIndent=1>BX</listItem>
* <listItem listType="bulleted" listIndent=2>Y/listItem>
* <listItem listType="bulleted" listIndent=2>C</listItem>
* ```
*/
export const modelIndentPasteFixer = function (evt, [content, selectable]) {
const model = this;
// Check whether inserted content starts from a `listItem`. If it does not, it means that there are some other
// elements before it and there is no need to fix indents, because even if we insert that content into a list,
// that list will be broken.
// Note: we also need to handle singular elements because inserting item with indent 0 into 0,1,[],2
// would create incorrect model.
let item = content.is('documentFragment') ? content.getChild(0) : content;
let selection;
if (!selectable) {
selection = model.document.selection;
}
else {
selection = model.createSelection(selectable);
}
if (item && item.is('element', 'listItem')) {
// Get a reference list item. Inserted list items will be fixed according to that item.
const pos = selection.getFirstPosition();
let refItem = null;
if (pos.parent.is('element', 'listItem')) {
refItem = pos.parent;
}
else if (pos.nodeBefore && pos.nodeBefore.is('element', 'listItem')) {
refItem = pos.nodeBefore;
}
// If there is `refItem` it means that we do insert list items into an existing list.
if (refItem) {
// First list item in `data` has indent equal to 0 (it is a first list item). It should have indent equal
// to the indent of reference item. We have to fix the first item and all of it's children and following siblings.
// Indent of all those items has to be adjusted to reference item.
const indentChange = refItem.getAttribute('listIndent');
// Fix only if there is anything to fix.
if (indentChange > 0) {
// Adjust indent of all "first" list items in inserted data.
while (item && item.is('element', 'listItem')) {
item._setAttribute('listIndent', item.getAttribute('listIndent') + indentChange);
item = item.nextSibling;
}
}
}
}
};
/**
* Helper function that converts children of a given `<li>` view element into corresponding model elements.
* The function maintains proper order of elements if model `listItem` is split during the conversion
* due to block children conversion.
*
* @param listItemModel List item model element to which converted children will be inserted.
* @param viewChildren View elements which will be converted.
* @param conversionApi Conversion interface to be used by the callback.
* @returns Position on which next elements should be inserted after children conversion.
*/
function viewToModelListItemChildrenConverter(listItemModel, viewChildren, conversionApi) {
const { writer, schema } = conversionApi;
// A position after the last inserted `listItem`.
let nextPosition = writer.createPositionAfter(listItemModel);
// Check all children of the converted `<li>`. At this point we assume there are no "whitespace" view text nodes
// in view list, between view list items. This should be handled by `<ul>` and `<ol>` converters.
for (const child of viewChildren) {
if (child.name == 'ul' || child.name == 'ol') {
// If the children is a list, we will insert its conversion result after currently handled `listItem`.
// Then, next insertion position will be set after all the new list items (and maybe other elements if
// something split list item).
//
// If this is a list, we expect that some `listItem`s and possibly other blocks will be inserted, however `.modelCursor`
// should be set after last `listItem` (or block). This is why it feels safe to use it as `nextPosition`
nextPosition = conversionApi.convertItem(child, nextPosition).modelCursor;
}
else {
// If this is not a list, try inserting content at the end of the currently handled `listItem`.
const result = conversionApi.convertItem(child, writer.createPositionAt(listItemModel, 'end'));
// It may end up that the current `listItem` becomes split (if that content cannot be inside `listItem`). For example:
//
// <li><p>Foo</p></li>
//
// will be converted to:
//
// <listItem></listItem><paragraph>Foo</paragraph><listItem></listItem>
//
const convertedChild = result.modelRange.start.nodeAfter;
const wasSplit = convertedChild && convertedChild.is('element') && !schema.checkChild(listItemModel, convertedChild.name);
if (wasSplit) {
// As `lastListItem` got split, we need to update it to the second part of the split `listItem` element.
//
// `modelCursor` should be set to a position where the conversion should continue. There are multiple possible scenarios
// that may happen. Usually, `modelCursor` (marked as `#` below) would point to the second list item after conversion:
//
// `<li><p>Foo</p></li>` -> `<listItem></listItem><paragraph>Foo</paragraph><listItem>#</listItem>`
//
// However, in some cases, like auto-paragraphing, the position is placed at the end of the block element:
//
// `<li><div>Foo</div></li>` -> `<listItem></listItem><paragraph>Foo#</paragraph><listItem></listItem>`
//
// or after an element if another element broken auto-paragraphed element:
//
// `<li><div><h2>Foo</h2></div></li>` -> `<listItem></listItem><heading1>Foo</heading1>#<listItem></listItem>`
//
// We need to check for such cases and use proper list item and position based on it.
//
if (result.modelCursor.parent.is('element', 'listItem')) {
// (1).
listItemModel = result.modelCursor.parent;
}
else {
// (2), (3).
listItemModel = findNextListItem(result.modelCursor);
}
nextPosition = writer.createPositionAfter(listItemModel);
}
}
}
return nextPosition;
}
/**
* Helper function that seeks for a next list item starting from given `startPosition`.
*/
function findNextListItem(startPosition) {
const treeWalker = new TreeWalker({ startPosition });
let value;
do {
value = treeWalker.next();
} while (!value.value.item.is('element', 'listItem'));
return value.value.item;
}
/**
* Helper function that takes all children of given `viewRemovedItem` and moves them in a correct place, according
* to other given parameters.
*/
function hoistNestedLists(nextIndent, modelRemoveStartPosition, viewRemoveStartPosition, viewRemovedItem, conversionApi, model) {
// Find correct previous model list item element.
// The element has to have either same or smaller indent than given reference indent.
// This will be the model element which will get nested items (if it has smaller indent) or sibling items (if it has same indent).
// Keep in mind that such element might not be found, if removed item was the first item.
const prevModelItem = getSiblingListItem(modelRemoveStartPosition.nodeBefore, {
sameIndent: true,
smallerIndent: true,
listIndent: nextIndent
});
const mapper = conversionApi.mapper;
const viewWriter = conversionApi.writer;
// Indent of found element or `null` if the element has not been found.
const prevIndent = prevModelItem ? prevModelItem.getAttribute('listIndent') : null;
let insertPosition;
if (!prevModelItem) {
// If element has not been found, simply insert lists at the position where the removed item was:
//
// Lorem ipsum.
// 1 -------- <--- this is removed, no previous list item, put nested items in place of removed item.
// 1.1 -------- <--- this is reference indent.
// 1.1.1 --------
// 1.1.2 --------
// 1.2 --------
//
// Becomes:
//
// Lorem ipsum.
// 1.1 --------
// 1.1.1 --------
// 1.1.2 --------
// 1.2 --------
insertPosition = viewRemoveStartPosition;
}
else if (prevIndent == nextIndent) {
// If element has been found and has same indent as reference indent it means that nested items should
// become siblings of found element:
//
// 1 --------
// 1.1 --------
// 1.2 -------- <--- this is `prevModelItem`.
// 2 -------- <--- this is removed, previous list item has indent same as reference indent.
// 2.1 -------- <--- this is reference indent, this and 2.2 should become siblings of 1.2.
// 2.2 --------
//
// Becomes:
//
// 1 --------
// 1.1 --------
// 1.2 --------
// 2.1 --------
// 2.2 --------
const prevViewList = mapper.toViewElement(prevModelItem).parent;
insertPosition = viewWriter.createPositionAfter(prevViewList);
}
else {
// If element has been found and has smaller indent as reference indent it means that nested items
// should become nested items of found item:
//
// 1 -------- <--- this is `prevModelItem`.
// 1.1 -------- <--- this is removed, previous list item has indent smaller than reference indent.
// 1.1.1 -------- <--- this is reference indent, this and 1.1.1 should become nested items of 1.
// 1.1.2 --------
// 1.2 --------
//
// Becomes:
//
// 1 --------
// 1.1.1 --------
// 1.1.2 --------
// 1.2 --------
//
// Note: in this case 1.1.1 have indent 2 while 1 have indent 0. In model that should not be possible,
// because following item may have indent bigger only by one. But this is fixed by postfixer.
const modelPosition = model.createPositionAt(prevModelItem, 'end');
insertPosition = mapper.toViewPosition(modelPosition);
}
insertPosition = positionAfterUiElements(insertPosition);
// Handle multiple lists. This happens if list item has nested numbered and bulleted lists. Following lists
// are inserted after the first list (no need to recalculate insertion position for them).
for (const child of [...viewRemovedItem.getChildren()]) {
if (isList(child)) {
insertPosition = viewWriter.move(viewWriter.createRangeOn(child), insertPosition).end;
mergeViewLists(viewWriter, child, child.nextSibling);
mergeViewLists(viewWriter, child.previousSibling, child);
}
}
}
/**
* Checks if view element is a list type (ul or ol).
*/
function isList(viewElement) {
return viewElement.is('element', 'ol') || viewElement.is('element', 'ul');
}
/**
* Calculates the indent value for a list item. Handles HTML compliant and non-compliant lists.
*
* Also, fixes non HTML compliant lists indents:
*
* ```
* before: fixed list:
* OL OL
* |-> LI (parent LIs: 0) |-> LI (indent: 0)
* |-> OL |-> OL
* |-> OL |
* | |-> OL |
* | |-> OL |
* | |-> LI (parent LIs: 1) |-> LI (indent: 1)
* |-> LI (parent LIs: 1) |-> LI (indent: 1)
*
* before: fixed list:
* OL OL
* |-> OL |
* |-> OL |
* |-> OL |
* |-> LI (parent LIs: 0) |-> LI (indent: 0)
*
* before: fixed list:
* OL OL
* |-> LI (parent LIs: 0) |-> LI (indent: 0)
* |-> OL |-> OL
* |-> LI (parent LIs: 0) |-> LI (indent: 1)
* ```
*/
function getIndent(listItem) {
let indent = 0;
let parent = listItem.parent;
while (parent) {
// Each LI in the tree will result in an increased indent for HTML compliant lists.
if (parent.is('element', 'li')) {
indent++;
}
else {
// If however the list is nested in other list we should check previous sibling of any of the list elements...
const previousSibling = parent.previousSibling;
// ...because the we might need increase its indent:
// before: fixed list:
// OL OL
// |-> LI (parent LIs: 0) |-> LI (indent: 0)
// |-> OL |-> OL
// |-> LI (parent LIs: 0) |-> LI (indent: 1)
if (previousSibling && previousSibling.is('element', 'li')) {
indent++;
}
}
parent = parent.parent;
}
return indent;
}