mirror of
https://github.com/overleaf/overleaf.git
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a6f05109a3
[misc] fix eslint violations for `no-var` GitOrigin-RevId: c52e82f3a8a993b8662cc5aa56e7b95ca3c55832
839 lines
28 KiB
JavaScript
839 lines
28 KiB
JavaScript
/* eslint-disable
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camelcase,
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max-len,
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no-return-assign,
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no-unused-vars,
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*/
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// TODO: This file was created by bulk-decaffeinate.
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// Fix any style issues and re-enable lint.
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/*
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* decaffeinate suggestions:
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* DS101: Remove unnecessary use of Array.from
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* DS102: Remove unnecessary code created because of implicit returns
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* DS205: Consider reworking code to avoid use of IIFEs
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* DS207: Consider shorter variations of null checks
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* Full docs: https://github.com/decaffeinate/decaffeinate/blob/master/docs/suggestions.md
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*/
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// This file is shared between document-updater and web, so that the server and client share
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// an identical track changes implementation. Do not edit it directly in web or document-updater,
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// instead edit it at https://github.com/sharelatex/ranges-tracker, where it has a suite of tests
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let RangesTracker
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export default RangesTracker = class RangesTracker {
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// The purpose of this class is to track a set of inserts and deletes to a document, like
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// track changes in Word. We store these as a set of ShareJs style ranges:
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// {i: "foo", p: 42} # Insert 'foo' at offset 42
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// {d: "bar", p: 37} # Delete 'bar' at offset 37
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// We only track the inserts and deletes, not the whole document, but by being given all
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// updates that are applied to a document, we can update these appropriately.
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//
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// Note that the set of inserts and deletes we store applies to the document as-is at the moment.
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// So inserts correspond to text which is in the document, while deletes correspond to text which
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// is no longer there, so their lengths do not affect the position of later offsets.
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// E.g.
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// this is the current text of the document
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// |-----| |
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// {i: "current ", p:12} -^ ^- {d: "old ", p: 31}
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//
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// Track changes rules (should be consistent with Word):
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// * When text is inserted at a delete, the text goes to the left of the delete
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// I.e. "foo|bar" -> "foobaz|bar", where | is the delete, and 'baz' is inserted
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// * Deleting content flagged as 'inserted' does not create a new delete marker, it only
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// removes the insert marker. E.g.
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// * "abdefghijkl" -> "abfghijkl" when 'de' is deleted. No delete marker added
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// |---| <- inserted |-| <- inserted
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// * Deletes overlapping regular text and inserted text will insert a delete marker for the
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// regular text:
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// "abcdefghijkl" -> "abcdejkl" when 'fghi' is deleted
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// |----| |--||
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// ^- inserted 'bcdefg' \ ^- deleted 'hi'
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// \--inserted 'bcde'
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// * Deletes overlapping other deletes are merged. E.g.
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// "abcghijkl" -> "ahijkl" when 'bcg is deleted'
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// | <- delete 'def' | <- delete 'bcdefg'
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// * Deletes by another user will consume deletes by the first user
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// * Inserts by another user will not combine with inserts by the first user. If they are in the
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// middle of a previous insert by the first user, the original insert will be split into two.
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constructor(changes, comments) {
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if (changes == null) {
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changes = []
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}
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this.changes = changes
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if (comments == null) {
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comments = []
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}
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this.comments = comments
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this.setIdSeed(RangesTracker.generateIdSeed())
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this.resetDirtyState()
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}
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getIdSeed() {
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return this.id_seed
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}
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setIdSeed(seed) {
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this.id_seed = seed
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return (this.id_increment = 0)
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}
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static generateIdSeed() {
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// Generate a the first 18 characters of Mongo ObjectId, leaving 6 for the increment part
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// Reference: https://github.com/dreampulse/ObjectId.js/blob/master/src/main/javascript/Objectid.js
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const pid = Math.floor(Math.random() * 32767).toString(16)
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const machine = Math.floor(Math.random() * 16777216).toString(16)
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const timestamp = Math.floor(new Date().valueOf() / 1000).toString(16)
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return (
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'00000000'.substr(0, 8 - timestamp.length) +
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timestamp +
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'000000'.substr(0, 6 - machine.length) +
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machine +
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'0000'.substr(0, 4 - pid.length) +
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pid
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)
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}
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static generateId() {
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return this.generateIdSeed() + '000001'
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}
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newId() {
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this.id_increment++
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const increment = this.id_increment.toString(16)
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const id =
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this.id_seed + '000000'.substr(0, 6 - increment.length) + increment
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return id
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}
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getComment(comment_id) {
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let comment = null
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for (const c of Array.from(this.comments)) {
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if (c.id === comment_id) {
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comment = c
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break
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}
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}
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return comment
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}
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removeCommentId(comment_id) {
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const comment = this.getComment(comment_id)
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if (comment == null) {
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return
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}
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this.comments = this.comments.filter(c => c.id !== comment_id)
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return this._markAsDirty(comment, 'comment', 'removed')
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}
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moveCommentId(comment_id, position, text) {
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return (() => {
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const result = []
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for (const comment of Array.from(this.comments)) {
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if (comment.id === comment_id) {
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comment.op.p = position
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comment.op.c = text
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result.push(this._markAsDirty(comment, 'comment', 'moved'))
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} else {
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result.push(undefined)
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}
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}
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return result
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})()
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}
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getChange(change_id) {
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let change = null
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for (const c of Array.from(this.changes)) {
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if (c.id === change_id) {
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change = c
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break
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}
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}
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return change
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}
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getChanges(change_ids) {
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const changes_response = []
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const ids_map = {}
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for (const change_id of Array.from(change_ids)) {
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ids_map[change_id] = true
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}
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for (const change of Array.from(this.changes)) {
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if (ids_map[change.id]) {
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delete ids_map[change.id]
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changes_response.push(change)
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}
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}
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return changes_response
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}
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removeChangeId(change_id) {
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const change = this.getChange(change_id)
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if (change == null) {
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return
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}
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return this._removeChange(change)
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}
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removeChangeIds(change_to_remove_ids) {
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if (
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!(change_to_remove_ids != null
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? change_to_remove_ids.length
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: undefined) > 0
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) {
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return
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}
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const i = this.changes.length
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const remove_change_id = {}
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for (const change_id of Array.from(change_to_remove_ids)) {
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remove_change_id[change_id] = true
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}
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const remaining_changes = []
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for (const change of Array.from(this.changes)) {
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if (remove_change_id[change.id]) {
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delete remove_change_id[change.id]
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this._markAsDirty(change, 'change', 'removed')
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} else {
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remaining_changes.push(change)
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}
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}
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return (this.changes = remaining_changes)
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}
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validate(text) {
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let content
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for (const change of Array.from(this.changes)) {
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if (change.op.i != null) {
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content = text.slice(change.op.p, change.op.p + change.op.i.length)
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if (content !== change.op.i) {
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throw new Error(
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`Change (${JSON.stringify(
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change
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)}) doesn't match text (${JSON.stringify(content)})`
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)
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}
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}
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}
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for (const comment of Array.from(this.comments)) {
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content = text.slice(comment.op.p, comment.op.p + comment.op.c.length)
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if (content !== comment.op.c) {
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throw new Error(
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`Comment (${JSON.stringify(
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comment
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)}) doesn't match text (${JSON.stringify(content)})`
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)
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}
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}
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return true
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}
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applyOp(op, metadata) {
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if (metadata == null) {
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metadata = {}
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}
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if (metadata.ts == null) {
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metadata.ts = new Date()
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}
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// Apply an op that has been applied to the document to our changes to keep them up to date
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if (op.i != null) {
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this.applyInsertToChanges(op, metadata)
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return this.applyInsertToComments(op)
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} else if (op.d != null) {
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this.applyDeleteToChanges(op, metadata)
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return this.applyDeleteToComments(op)
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} else if (op.c != null) {
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return this.addComment(op, metadata)
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} else {
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throw new Error('unknown op type')
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}
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}
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applyOps(ops, metadata) {
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if (metadata == null) {
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metadata = {}
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}
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return Array.from(ops).map(op => this.applyOp(op, metadata))
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}
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addComment(op, metadata) {
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const existing = this.getComment(op.t)
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if (existing != null) {
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this.moveCommentId(op.t, op.p, op.c)
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return existing
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} else {
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let comment
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this.comments.push(
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(comment = {
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id: op.t || this.newId(),
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op: {
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// Copy because we'll modify in place
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c: op.c,
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p: op.p,
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t: op.t,
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},
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metadata,
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})
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)
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this._markAsDirty(comment, 'comment', 'added')
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return comment
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}
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}
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applyInsertToComments(op) {
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return (() => {
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const result = []
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for (const comment of Array.from(this.comments)) {
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if (op.p <= comment.op.p) {
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comment.op.p += op.i.length
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result.push(this._markAsDirty(comment, 'comment', 'moved'))
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} else if (op.p < comment.op.p + comment.op.c.length) {
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const offset = op.p - comment.op.p
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comment.op.c =
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comment.op.c.slice(0, +(offset - 1) + 1 || undefined) +
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op.i +
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comment.op.c.slice(offset)
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result.push(this._markAsDirty(comment, 'comment', 'moved'))
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} else {
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result.push(undefined)
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}
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}
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return result
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})()
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}
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applyDeleteToComments(op) {
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const op_start = op.p
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const op_length = op.d.length
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const op_end = op.p + op_length
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return (() => {
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const result = []
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for (const comment of Array.from(this.comments)) {
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const comment_start = comment.op.p
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const comment_end = comment.op.p + comment.op.c.length
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const comment_length = comment_end - comment_start
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if (op_end <= comment_start) {
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// delete is fully before comment
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comment.op.p -= op_length
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result.push(this._markAsDirty(comment, 'comment', 'moved'))
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} else if (op_start >= comment_end) {
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// delete is fully after comment, nothing to do
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} else {
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// delete and comment overlap
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let remaining_after, remaining_before
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if (op_start <= comment_start) {
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remaining_before = ''
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} else {
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remaining_before = comment.op.c.slice(0, op_start - comment_start)
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}
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if (op_end >= comment_end) {
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remaining_after = ''
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} else {
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remaining_after = comment.op.c.slice(op_end - comment_start)
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}
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// Check deleted content matches delete op
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const deleted_comment = comment.op.c.slice(
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remaining_before.length,
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comment_length - remaining_after.length
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)
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const offset = Math.max(0, comment_start - op_start)
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const deleted_op_content = op.d
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.slice(offset)
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.slice(0, deleted_comment.length)
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if (deleted_comment !== deleted_op_content) {
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throw new Error('deleted content does not match comment content')
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}
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comment.op.p = Math.min(comment_start, op_start)
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comment.op.c = remaining_before + remaining_after
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result.push(this._markAsDirty(comment, 'comment', 'moved'))
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}
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}
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return result
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})()
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}
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applyInsertToChanges(op, metadata) {
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let change
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const op_start = op.p
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const op_length = op.i.length
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const op_end = op.p + op_length
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const undoing = !!op.u
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let already_merged = false
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let previous_change = null
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const moved_changes = []
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const remove_changes = []
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const new_changes = []
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for (let i = 0; i < this.changes.length; i++) {
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change = this.changes[i]
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const change_start = change.op.p
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if (change.op.d != null) {
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// Shift any deletes after this along by the length of this insert
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if (op_start < change_start) {
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change.op.p += op_length
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moved_changes.push(change)
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} else if (op_start === change_start) {
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// If we are undoing, then we want to cancel any existing delete ranges if we can.
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// Check if the insert matches the start of the delete, and just remove it from the delete instead if so.
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if (
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undoing &&
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change.op.d.length >= op.i.length &&
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change.op.d.slice(0, op.i.length) === op.i
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) {
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change.op.d = change.op.d.slice(op.i.length)
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change.op.p += op.i.length
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if (change.op.d === '') {
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remove_changes.push(change)
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} else {
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moved_changes.push(change)
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}
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already_merged = true
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} else {
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change.op.p += op_length
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moved_changes.push(change)
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}
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}
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} else if (change.op.i != null) {
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let offset
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const change_end = change_start + change.op.i.length
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const is_change_overlapping =
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op_start >= change_start && op_start <= change_end
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// Only merge inserts if they are from the same user
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const is_same_user = metadata.user_id === change.metadata.user_id
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// If we are undoing, then our changes will be removed from any delete ops just after. In that case, if there is also
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// an insert op just before, then we shouldn't append it to this insert, but instead only cancel the following delete.
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// E.g.
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// foo|<--- about to insert 'b' here
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// inserted 'foo' --^ ^-- deleted 'bar'
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// should become just 'foo' not 'foob' (with the delete marker becoming just 'ar'), .
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const next_change = this.changes[i + 1]
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const is_op_adjacent_to_next_delete =
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next_change != null &&
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next_change.op.d != null &&
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op.p === change_end &&
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next_change.op.p === op.p
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|
const will_op_cancel_next_delete =
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undoing &&
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is_op_adjacent_to_next_delete &&
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next_change.op.d.slice(0, op.i.length) === op.i
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|
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// If there is a delete at the start of the insert, and we're inserting
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// at the start, we SHOULDN'T merge since the delete acts as a partition.
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// The previous op will be the delete, but it's already been shifted by this insert
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//
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// I.e.
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// Originally: |-- existing insert --|
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// | <- existing delete at same offset
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//
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// Now: |-- existing insert --| <- not shifted yet
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// |-- this insert --|| <- existing delete shifted along to end of this op
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//
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// After: |-- existing insert --|
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// |-- this insert --|| <- existing delete
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//
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// Without the delete, the inserts would be merged.
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const is_insert_blocked_by_delete =
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previous_change != null &&
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previous_change.op.d != null &&
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previous_change.op.p === op_end
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|
|
|
// If the insert is overlapping another insert, either at the beginning in the middle or touching the end,
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// then we merge them into one.
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|
if (
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this.track_changes &&
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|
is_change_overlapping &&
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!is_insert_blocked_by_delete &&
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!already_merged &&
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!will_op_cancel_next_delete &&
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is_same_user
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) {
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offset = op_start - change_start
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change.op.i =
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change.op.i.slice(0, offset) + op.i + change.op.i.slice(offset)
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change.metadata.ts = metadata.ts
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already_merged = true
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moved_changes.push(change)
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|
} else if (op_start <= change_start) {
|
|
// If we're fully before the other insert we can just shift the other insert by our length.
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|
// If they are touching, and should have been merged, they will have been above.
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|
// If not merged above, then it must be blocked by a delete, and will be after this insert, so we shift it along as well
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change.op.p += op_length
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moved_changes.push(change)
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|
} else if (
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|
(!is_same_user || !this.track_changes) &&
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|
change_start < op_start &&
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op_start < change_end
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) {
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|
// This user is inserting inside a change by another user, so we need to split the
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|
// other user's change into one before and after this one.
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|
offset = op_start - change_start
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const before_content = change.op.i.slice(0, offset)
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|
const after_content = change.op.i.slice(offset)
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|
|
|
// The existing change can become the 'before' change
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|
change.op.i = before_content
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moved_changes.push(change)
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|
|
// Create a new op afterwards
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|
const after_change = {
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|
op: {
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i: after_content,
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p: change_start + offset + op_length,
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},
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metadata: {},
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|
}
|
|
for (const key in change.metadata) {
|
|
const value = change.metadata[key]
|
|
after_change.metadata[key] = value
|
|
}
|
|
new_changes.push(after_change)
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|
}
|
|
}
|
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previous_change = change
|
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}
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|
|
if (this.track_changes && !already_merged) {
|
|
this._addOp(op, metadata)
|
|
}
|
|
for ({ op, metadata } of Array.from(new_changes)) {
|
|
this._addOp(op, metadata)
|
|
}
|
|
|
|
for (change of Array.from(remove_changes)) {
|
|
this._removeChange(change)
|
|
}
|
|
|
|
return (() => {
|
|
const result = []
|
|
for (change of Array.from(moved_changes)) {
|
|
result.push(this._markAsDirty(change, 'change', 'moved'))
|
|
}
|
|
return result
|
|
})()
|
|
}
|
|
|
|
applyDeleteToChanges(op, metadata) {
|
|
const op_start = op.p
|
|
const op_length = op.d.length
|
|
const op_end = op.p + op_length
|
|
const remove_changes = []
|
|
let moved_changes = []
|
|
|
|
// We might end up modifying our delete op if it merges with existing deletes, or cancels out
|
|
// with an existing insert. Since we might do multiple modifications, we record them and do
|
|
// all the modifications after looping through the existing changes, so as not to mess up the
|
|
// offset indexes as we go.
|
|
const op_modifications = []
|
|
for (const change of Array.from(this.changes)) {
|
|
let change_start
|
|
if (change.op.i != null) {
|
|
change_start = change.op.p
|
|
const change_end = change_start + change.op.i.length
|
|
if (op_end <= change_start) {
|
|
// Shift ops after us back by our length
|
|
change.op.p -= op_length
|
|
moved_changes.push(change)
|
|
} else if (op_start >= change_end) {
|
|
// Delete is after insert, nothing to do
|
|
} else {
|
|
// When the new delete overlaps an insert, we should remove the part of the insert that
|
|
// is now deleted, and also remove the part of the new delete that overlapped. I.e.
|
|
// the two cancel out where they overlap.
|
|
let delete_remaining_after,
|
|
delete_remaining_before,
|
|
insert_remaining_after,
|
|
insert_remaining_before
|
|
if (op_start >= change_start) {
|
|
// |-- existing insert --|
|
|
// insert_remaining_before -> |.....||-- new delete --|
|
|
delete_remaining_before = ''
|
|
insert_remaining_before = change.op.i.slice(
|
|
0,
|
|
op_start - change_start
|
|
)
|
|
} else {
|
|
// delete_remaining_before -> |.....||-- existing insert --|
|
|
// |-- new delete --|
|
|
delete_remaining_before = op.d.slice(0, change_start - op_start)
|
|
insert_remaining_before = ''
|
|
}
|
|
|
|
if (op_end <= change_end) {
|
|
// |-- existing insert --|
|
|
// |-- new delete --||.....| <- insert_remaining_after
|
|
delete_remaining_after = ''
|
|
insert_remaining_after = change.op.i.slice(op_end - change_start)
|
|
} else {
|
|
// |-- existing insert --||.....| <- delete_remaining_after
|
|
// |-- new delete --|
|
|
delete_remaining_after = op.d.slice(change_end - op_start)
|
|
insert_remaining_after = ''
|
|
}
|
|
|
|
const insert_remaining =
|
|
insert_remaining_before + insert_remaining_after
|
|
if (insert_remaining.length > 0) {
|
|
change.op.i = insert_remaining
|
|
change.op.p = Math.min(change_start, op_start)
|
|
change.metadata.ts = metadata.ts
|
|
moved_changes.push(change)
|
|
} else {
|
|
remove_changes.push(change)
|
|
}
|
|
|
|
// We know what we want to preserve of our delete op before (delete_remaining_before) and what we want to preserve
|
|
// afterwards (delete_remaining_before). Now we need to turn that into a modification which deletes the
|
|
// chunk in the middle not covered by these.
|
|
const delete_removed_length =
|
|
op.d.length -
|
|
delete_remaining_before.length -
|
|
delete_remaining_after.length
|
|
const delete_removed_start = delete_remaining_before.length
|
|
const modification = {
|
|
d: op.d.slice(
|
|
delete_removed_start,
|
|
delete_removed_start + delete_removed_length
|
|
),
|
|
p: delete_removed_start,
|
|
}
|
|
if (modification.d.length > 0) {
|
|
op_modifications.push(modification)
|
|
}
|
|
}
|
|
} else if (change.op.d != null) {
|
|
change_start = change.op.p
|
|
if (
|
|
op_end < change_start ||
|
|
(!this.track_changes && op_end === change_start)
|
|
) {
|
|
// Shift ops after us back by our length.
|
|
// If we're tracking changes, it must be strictly before, since we'll merge
|
|
// below if they are touching. Otherwise, touching is fine.
|
|
change.op.p -= op_length
|
|
moved_changes.push(change)
|
|
} else if (op_start <= change_start && change_start <= op_end) {
|
|
if (this.track_changes) {
|
|
// If we overlap a delete, add it in our content, and delete the existing change.
|
|
// It's easier to do it this way, rather than modifying the existing delete in case
|
|
// we overlap many deletes and we'd need to track that. We have a workaround to
|
|
// update the delete in place if possible below.
|
|
const offset = change_start - op_start
|
|
op_modifications.push({ i: change.op.d, p: offset })
|
|
remove_changes.push(change)
|
|
} else {
|
|
change.op.p = op_start
|
|
moved_changes.push(change)
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// Copy rather than modify because we still need to apply it to comments
|
|
op = {
|
|
p: op.p,
|
|
d: this._applyOpModifications(op.d, op_modifications),
|
|
}
|
|
|
|
for (const change of Array.from(remove_changes)) {
|
|
// This is a bit of hack to avoid removing one delete and replacing it with another.
|
|
// If we don't do this, it causes the UI to flicker
|
|
if (
|
|
op.d.length > 0 &&
|
|
change.op.d != null &&
|
|
op.p <= change.op.p &&
|
|
change.op.p <= op.p + op.d.length
|
|
) {
|
|
change.op.p = op.p
|
|
change.op.d = op.d
|
|
change.metadata = metadata
|
|
moved_changes.push(change)
|
|
op.d = '' // stop it being added
|
|
} else {
|
|
this._removeChange(change)
|
|
}
|
|
}
|
|
|
|
if (this.track_changes && op.d.length > 0) {
|
|
this._addOp(op, metadata)
|
|
} else {
|
|
// It's possible that we deleted an insert between two other inserts. I.e.
|
|
// If we delete 'user_2 insert' in:
|
|
// |-- user_1 insert --||-- user_2 insert --||-- user_1 insert --|
|
|
// it becomes:
|
|
// |-- user_1 insert --||-- user_1 insert --|
|
|
// We need to merge these together again
|
|
const results = this._scanAndMergeAdjacentUpdates()
|
|
moved_changes = moved_changes.concat(results.moved_changes)
|
|
for (const change of Array.from(results.remove_changes)) {
|
|
this._removeChange(change)
|
|
moved_changes = moved_changes.filter(c => c !== change)
|
|
}
|
|
}
|
|
|
|
return (() => {
|
|
const result = []
|
|
for (const change of Array.from(moved_changes)) {
|
|
result.push(this._markAsDirty(change, 'change', 'moved'))
|
|
}
|
|
return result
|
|
})()
|
|
}
|
|
|
|
_addOp(op, metadata) {
|
|
const change = {
|
|
id: this.newId(),
|
|
op: this._clone(op), // Don't take a reference to the existing op since we'll modify this in place with future changes
|
|
metadata: this._clone(metadata),
|
|
}
|
|
this.changes.push(change)
|
|
|
|
// Keep ops in order of offset, with deletes before inserts
|
|
this.changes.sort(function (c1, c2) {
|
|
const result = c1.op.p - c2.op.p
|
|
if (result !== 0) {
|
|
return result
|
|
} else if (c1.op.i != null && c2.op.d != null) {
|
|
return 1
|
|
} else if (c1.op.d != null && c2.op.i != null) {
|
|
return -1
|
|
} else {
|
|
return 0
|
|
}
|
|
})
|
|
|
|
return this._markAsDirty(change, 'change', 'added')
|
|
}
|
|
|
|
_removeChange(change) {
|
|
this.changes = this.changes.filter(c => c.id !== change.id)
|
|
return this._markAsDirty(change, 'change', 'removed')
|
|
}
|
|
|
|
_applyOpModifications(content, op_modifications) {
|
|
// Put in descending position order, with deleting first if at the same offset
|
|
// (Inserting first would modify the content that the delete will delete)
|
|
op_modifications.sort(function (a, b) {
|
|
const result = b.p - a.p
|
|
if (result !== 0) {
|
|
return result
|
|
} else if (a.i != null && b.d != null) {
|
|
return 1
|
|
} else if (a.d != null && b.i != null) {
|
|
return -1
|
|
} else {
|
|
return 0
|
|
}
|
|
})
|
|
|
|
for (const modification of Array.from(op_modifications)) {
|
|
if (modification.i != null) {
|
|
content =
|
|
content.slice(0, modification.p) +
|
|
modification.i +
|
|
content.slice(modification.p)
|
|
} else if (modification.d != null) {
|
|
if (
|
|
content.slice(
|
|
modification.p,
|
|
modification.p + modification.d.length
|
|
) !== modification.d
|
|
) {
|
|
throw new Error(
|
|
`deleted content does not match. content: ${JSON.stringify(
|
|
content
|
|
)}; modification: ${JSON.stringify(modification)}`
|
|
)
|
|
}
|
|
content =
|
|
content.slice(0, modification.p) +
|
|
content.slice(modification.p + modification.d.length)
|
|
}
|
|
}
|
|
return content
|
|
}
|
|
|
|
_scanAndMergeAdjacentUpdates() {
|
|
// This should only need calling when deleting an update between two
|
|
// other updates. There's no other way to get two adjacent updates from the
|
|
// same user, since they would be merged on insert.
|
|
let previous_change = null
|
|
const remove_changes = []
|
|
const moved_changes = []
|
|
for (const change of Array.from(this.changes)) {
|
|
if (
|
|
(previous_change != null ? previous_change.op.i : undefined) != null &&
|
|
change.op.i != null
|
|
) {
|
|
const previous_change_end =
|
|
previous_change.op.p + previous_change.op.i.length
|
|
const previous_change_user_id = previous_change.metadata.user_id
|
|
const change_start = change.op.p
|
|
const change_user_id = change.metadata.user_id
|
|
if (
|
|
previous_change_end === change_start &&
|
|
previous_change_user_id === change_user_id
|
|
) {
|
|
remove_changes.push(change)
|
|
previous_change.op.i += change.op.i
|
|
moved_changes.push(previous_change)
|
|
}
|
|
} else if (
|
|
(previous_change != null ? previous_change.op.d : undefined) != null &&
|
|
change.op.d != null &&
|
|
previous_change.op.p === change.op.p
|
|
) {
|
|
// Merge adjacent deletes
|
|
previous_change.op.d += change.op.d
|
|
remove_changes.push(change)
|
|
moved_changes.push(previous_change)
|
|
} else {
|
|
// Only update to the current change if we haven't removed it.
|
|
previous_change = change
|
|
}
|
|
}
|
|
return { moved_changes, remove_changes }
|
|
}
|
|
|
|
resetDirtyState() {
|
|
return (this._dirtyState = {
|
|
comment: {
|
|
moved: {},
|
|
removed: {},
|
|
added: {},
|
|
},
|
|
change: {
|
|
moved: {},
|
|
removed: {},
|
|
added: {},
|
|
},
|
|
})
|
|
}
|
|
|
|
getDirtyState() {
|
|
return this._dirtyState
|
|
}
|
|
|
|
_markAsDirty(object, type, action) {
|
|
return (this._dirtyState[type][action][object.id] = object)
|
|
}
|
|
|
|
_clone(object) {
|
|
const clone = {}
|
|
for (const k in object) {
|
|
const v = object[k]
|
|
clone[k] = v
|
|
}
|
|
return clone
|
|
}
|
|
}
|