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- 'use strict';
- Object.defineProperty(exports, '__esModule', {
- value: true
- });
- exports.cleanupSemantic =
- exports.Diff =
- exports.DIFF_INSERT =
- exports.DIFF_EQUAL =
- exports.DIFF_DELETE =
- void 0;
- function _defineProperty(obj, key, value) {
- if (key in obj) {
- Object.defineProperty(obj, key, {
- value: value,
- enumerable: true,
- configurable: true,
- writable: true
- });
- } else {
- obj[key] = value;
- }
- return obj;
- }
- /**
- * Diff Match and Patch
- * Copyright 2018 The diff-match-patch Authors.
- * https://github.com/google/diff-match-patch
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
- /**
- * @fileoverview Computes the difference between two texts to create a patch.
- * Applies the patch onto another text, allowing for errors.
- * @author fraser@google.com (Neil Fraser)
- */
- /**
- * CHANGES by pedrottimark to diff_match_patch_uncompressed.ts file:
- *
- * 1. Delete anything not needed to use diff_cleanupSemantic method
- * 2. Convert from prototype properties to var declarations
- * 3. Convert Diff to class from constructor and prototype
- * 4. Add type annotations for arguments and return values
- * 5. Add exports
- */
- /**
- * The data structure representing a diff is an array of tuples:
- * [[DIFF_DELETE, 'Hello'], [DIFF_INSERT, 'Goodbye'], [DIFF_EQUAL, ' world.']]
- * which means: delete 'Hello', add 'Goodbye' and keep ' world.'
- */
- var DIFF_DELETE = -1;
- exports.DIFF_DELETE = DIFF_DELETE;
- var DIFF_INSERT = 1;
- exports.DIFF_INSERT = DIFF_INSERT;
- var DIFF_EQUAL = 0;
- /**
- * Class representing one diff tuple.
- * Attempts to look like a two-element array (which is what this used to be).
- * @param {number} op Operation, one of: DIFF_DELETE, DIFF_INSERT, DIFF_EQUAL.
- * @param {string} text Text to be deleted, inserted, or retained.
- * @constructor
- */
- exports.DIFF_EQUAL = DIFF_EQUAL;
- class Diff {
- constructor(op, text) {
- _defineProperty(this, 0, void 0);
- _defineProperty(this, 1, void 0);
- this[0] = op;
- this[1] = text;
- }
- }
- /**
- * Determine the common prefix of two strings.
- * @param {string} text1 First string.
- * @param {string} text2 Second string.
- * @return {number} The number of characters common to the start of each
- * string.
- */
- exports.Diff = Diff;
- var diff_commonPrefix = function (text1, text2) {
- // Quick check for common null cases.
- if (!text1 || !text2 || text1.charAt(0) != text2.charAt(0)) {
- return 0;
- } // Binary search.
- // Performance analysis: https://neil.fraser.name/news/2007/10/09/
- var pointermin = 0;
- var pointermax = Math.min(text1.length, text2.length);
- var pointermid = pointermax;
- var pointerstart = 0;
- while (pointermin < pointermid) {
- if (
- text1.substring(pointerstart, pointermid) ==
- text2.substring(pointerstart, pointermid)
- ) {
- pointermin = pointermid;
- pointerstart = pointermin;
- } else {
- pointermax = pointermid;
- }
- pointermid = Math.floor((pointermax - pointermin) / 2 + pointermin);
- }
- return pointermid;
- };
- /**
- * Determine the common suffix of two strings.
- * @param {string} text1 First string.
- * @param {string} text2 Second string.
- * @return {number} The number of characters common to the end of each string.
- */
- var diff_commonSuffix = function (text1, text2) {
- // Quick check for common null cases.
- if (
- !text1 ||
- !text2 ||
- text1.charAt(text1.length - 1) != text2.charAt(text2.length - 1)
- ) {
- return 0;
- } // Binary search.
- // Performance analysis: https://neil.fraser.name/news/2007/10/09/
- var pointermin = 0;
- var pointermax = Math.min(text1.length, text2.length);
- var pointermid = pointermax;
- var pointerend = 0;
- while (pointermin < pointermid) {
- if (
- text1.substring(text1.length - pointermid, text1.length - pointerend) ==
- text2.substring(text2.length - pointermid, text2.length - pointerend)
- ) {
- pointermin = pointermid;
- pointerend = pointermin;
- } else {
- pointermax = pointermid;
- }
- pointermid = Math.floor((pointermax - pointermin) / 2 + pointermin);
- }
- return pointermid;
- };
- /**
- * Determine if the suffix of one string is the prefix of another.
- * @param {string} text1 First string.
- * @param {string} text2 Second string.
- * @return {number} The number of characters common to the end of the first
- * string and the start of the second string.
- * @private
- */
- var diff_commonOverlap_ = function (text1, text2) {
- // Cache the text lengths to prevent multiple calls.
- var text1_length = text1.length;
- var text2_length = text2.length; // Eliminate the null case.
- if (text1_length == 0 || text2_length == 0) {
- return 0;
- } // Truncate the longer string.
- if (text1_length > text2_length) {
- text1 = text1.substring(text1_length - text2_length);
- } else if (text1_length < text2_length) {
- text2 = text2.substring(0, text1_length);
- }
- var text_length = Math.min(text1_length, text2_length); // Quick check for the worst case.
- if (text1 == text2) {
- return text_length;
- } // Start by looking for a single character match
- // and increase length until no match is found.
- // Performance analysis: https://neil.fraser.name/news/2010/11/04/
- var best = 0;
- var length = 1;
- while (true) {
- var pattern = text1.substring(text_length - length);
- var found = text2.indexOf(pattern);
- if (found == -1) {
- return best;
- }
- length += found;
- if (
- found == 0 ||
- text1.substring(text_length - length) == text2.substring(0, length)
- ) {
- best = length;
- length++;
- }
- }
- };
- /**
- * Reduce the number of edits by eliminating semantically trivial equalities.
- * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
- */
- var diff_cleanupSemantic = function (diffs) {
- var changes = false;
- var equalities = []; // Stack of indices where equalities are found.
- var equalitiesLength = 0; // Keeping our own length var is faster in JS.
- /** @type {?string} */
- var lastEquality = null; // Always equal to diffs[equalities[equalitiesLength - 1]][1]
- var pointer = 0; // Index of current position.
- // Number of characters that changed prior to the equality.
- var length_insertions1 = 0;
- var length_deletions1 = 0; // Number of characters that changed after the equality.
- var length_insertions2 = 0;
- var length_deletions2 = 0;
- while (pointer < diffs.length) {
- if (diffs[pointer][0] == DIFF_EQUAL) {
- // Equality found.
- equalities[equalitiesLength++] = pointer;
- length_insertions1 = length_insertions2;
- length_deletions1 = length_deletions2;
- length_insertions2 = 0;
- length_deletions2 = 0;
- lastEquality = diffs[pointer][1];
- } else {
- // An insertion or deletion.
- if (diffs[pointer][0] == DIFF_INSERT) {
- length_insertions2 += diffs[pointer][1].length;
- } else {
- length_deletions2 += diffs[pointer][1].length;
- } // Eliminate an equality that is smaller or equal to the edits on both
- // sides of it.
- if (
- lastEquality &&
- lastEquality.length <=
- Math.max(length_insertions1, length_deletions1) &&
- lastEquality.length <= Math.max(length_insertions2, length_deletions2)
- ) {
- // Duplicate record.
- diffs.splice(
- equalities[equalitiesLength - 1],
- 0,
- new Diff(DIFF_DELETE, lastEquality)
- ); // Change second copy to insert.
- diffs[equalities[equalitiesLength - 1] + 1][0] = DIFF_INSERT; // Throw away the equality we just deleted.
- equalitiesLength--; // Throw away the previous equality (it needs to be reevaluated).
- equalitiesLength--;
- pointer = equalitiesLength > 0 ? equalities[equalitiesLength - 1] : -1;
- length_insertions1 = 0; // Reset the counters.
- length_deletions1 = 0;
- length_insertions2 = 0;
- length_deletions2 = 0;
- lastEquality = null;
- changes = true;
- }
- }
- pointer++;
- } // Normalize the diff.
- if (changes) {
- diff_cleanupMerge(diffs);
- }
- diff_cleanupSemanticLossless(diffs); // Find any overlaps between deletions and insertions.
- // e.g: <del>abcxxx</del><ins>xxxdef</ins>
- // -> <del>abc</del>xxx<ins>def</ins>
- // e.g: <del>xxxabc</del><ins>defxxx</ins>
- // -> <ins>def</ins>xxx<del>abc</del>
- // Only extract an overlap if it is as big as the edit ahead or behind it.
- pointer = 1;
- while (pointer < diffs.length) {
- if (
- diffs[pointer - 1][0] == DIFF_DELETE &&
- diffs[pointer][0] == DIFF_INSERT
- ) {
- var deletion = diffs[pointer - 1][1];
- var insertion = diffs[pointer][1];
- var overlap_length1 = diff_commonOverlap_(deletion, insertion);
- var overlap_length2 = diff_commonOverlap_(insertion, deletion);
- if (overlap_length1 >= overlap_length2) {
- if (
- overlap_length1 >= deletion.length / 2 ||
- overlap_length1 >= insertion.length / 2
- ) {
- // Overlap found. Insert an equality and trim the surrounding edits.
- diffs.splice(
- pointer,
- 0,
- new Diff(DIFF_EQUAL, insertion.substring(0, overlap_length1))
- );
- diffs[pointer - 1][1] = deletion.substring(
- 0,
- deletion.length - overlap_length1
- );
- diffs[pointer + 1][1] = insertion.substring(overlap_length1);
- pointer++;
- }
- } else {
- if (
- overlap_length2 >= deletion.length / 2 ||
- overlap_length2 >= insertion.length / 2
- ) {
- // Reverse overlap found.
- // Insert an equality and swap and trim the surrounding edits.
- diffs.splice(
- pointer,
- 0,
- new Diff(DIFF_EQUAL, deletion.substring(0, overlap_length2))
- );
- diffs[pointer - 1][0] = DIFF_INSERT;
- diffs[pointer - 1][1] = insertion.substring(
- 0,
- insertion.length - overlap_length2
- );
- diffs[pointer + 1][0] = DIFF_DELETE;
- diffs[pointer + 1][1] = deletion.substring(overlap_length2);
- pointer++;
- }
- }
- pointer++;
- }
- pointer++;
- }
- };
- /**
- * Look for single edits surrounded on both sides by equalities
- * which can be shifted sideways to align the edit to a word boundary.
- * e.g: The c<ins>at c</ins>ame. -> The <ins>cat </ins>came.
- * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
- */
- exports.cleanupSemantic = diff_cleanupSemantic;
- var diff_cleanupSemanticLossless = function (diffs) {
- /**
- * Given two strings, compute a score representing whether the internal
- * boundary falls on logical boundaries.
- * Scores range from 6 (best) to 0 (worst).
- * Closure, but does not reference any external variables.
- * @param {string} one First string.
- * @param {string} two Second string.
- * @return {number} The score.
- * @private
- */
- function diff_cleanupSemanticScore_(one, two) {
- if (!one || !two) {
- // Edges are the best.
- return 6;
- } // Each port of this function behaves slightly differently due to
- // subtle differences in each language's definition of things like
- // 'whitespace'. Since this function's purpose is largely cosmetic,
- // the choice has been made to use each language's native features
- // rather than force total conformity.
- var char1 = one.charAt(one.length - 1);
- var char2 = two.charAt(0);
- var nonAlphaNumeric1 = char1.match(nonAlphaNumericRegex_);
- var nonAlphaNumeric2 = char2.match(nonAlphaNumericRegex_);
- var whitespace1 = nonAlphaNumeric1 && char1.match(whitespaceRegex_);
- var whitespace2 = nonAlphaNumeric2 && char2.match(whitespaceRegex_);
- var lineBreak1 = whitespace1 && char1.match(linebreakRegex_);
- var lineBreak2 = whitespace2 && char2.match(linebreakRegex_);
- var blankLine1 = lineBreak1 && one.match(blanklineEndRegex_);
- var blankLine2 = lineBreak2 && two.match(blanklineStartRegex_);
- if (blankLine1 || blankLine2) {
- // Five points for blank lines.
- return 5;
- } else if (lineBreak1 || lineBreak2) {
- // Four points for line breaks.
- return 4;
- } else if (nonAlphaNumeric1 && !whitespace1 && whitespace2) {
- // Three points for end of sentences.
- return 3;
- } else if (whitespace1 || whitespace2) {
- // Two points for whitespace.
- return 2;
- } else if (nonAlphaNumeric1 || nonAlphaNumeric2) {
- // One point for non-alphanumeric.
- return 1;
- }
- return 0;
- }
- var pointer = 1; // Intentionally ignore the first and last element (don't need checking).
- while (pointer < diffs.length - 1) {
- if (
- diffs[pointer - 1][0] == DIFF_EQUAL &&
- diffs[pointer + 1][0] == DIFF_EQUAL
- ) {
- // This is a single edit surrounded by equalities.
- var equality1 = diffs[pointer - 1][1];
- var edit = diffs[pointer][1];
- var equality2 = diffs[pointer + 1][1]; // First, shift the edit as far left as possible.
- var commonOffset = diff_commonSuffix(equality1, edit);
- if (commonOffset) {
- var commonString = edit.substring(edit.length - commonOffset);
- equality1 = equality1.substring(0, equality1.length - commonOffset);
- edit = commonString + edit.substring(0, edit.length - commonOffset);
- equality2 = commonString + equality2;
- } // Second, step character by character right, looking for the best fit.
- var bestEquality1 = equality1;
- var bestEdit = edit;
- var bestEquality2 = equality2;
- var bestScore =
- diff_cleanupSemanticScore_(equality1, edit) +
- diff_cleanupSemanticScore_(edit, equality2);
- while (edit.charAt(0) === equality2.charAt(0)) {
- equality1 += edit.charAt(0);
- edit = edit.substring(1) + equality2.charAt(0);
- equality2 = equality2.substring(1);
- var score =
- diff_cleanupSemanticScore_(equality1, edit) +
- diff_cleanupSemanticScore_(edit, equality2); // The >= encourages trailing rather than leading whitespace on edits.
- if (score >= bestScore) {
- bestScore = score;
- bestEquality1 = equality1;
- bestEdit = edit;
- bestEquality2 = equality2;
- }
- }
- if (diffs[pointer - 1][1] != bestEquality1) {
- // We have an improvement, save it back to the diff.
- if (bestEquality1) {
- diffs[pointer - 1][1] = bestEquality1;
- } else {
- diffs.splice(pointer - 1, 1);
- pointer--;
- }
- diffs[pointer][1] = bestEdit;
- if (bestEquality2) {
- diffs[pointer + 1][1] = bestEquality2;
- } else {
- diffs.splice(pointer + 1, 1);
- pointer--;
- }
- }
- }
- pointer++;
- }
- }; // Define some regex patterns for matching boundaries.
- var nonAlphaNumericRegex_ = /[^a-zA-Z0-9]/;
- var whitespaceRegex_ = /\s/;
- var linebreakRegex_ = /[\r\n]/;
- var blanklineEndRegex_ = /\n\r?\n$/;
- var blanklineStartRegex_ = /^\r?\n\r?\n/;
- /**
- * Reorder and merge like edit sections. Merge equalities.
- * Any edit section can move as long as it doesn't cross an equality.
- * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
- */
- var diff_cleanupMerge = function (diffs) {
- // Add a dummy entry at the end.
- diffs.push(new Diff(DIFF_EQUAL, ''));
- var pointer = 0;
- var count_delete = 0;
- var count_insert = 0;
- var text_delete = '';
- var text_insert = '';
- var commonlength;
- while (pointer < diffs.length) {
- switch (diffs[pointer][0]) {
- case DIFF_INSERT:
- count_insert++;
- text_insert += diffs[pointer][1];
- pointer++;
- break;
- case DIFF_DELETE:
- count_delete++;
- text_delete += diffs[pointer][1];
- pointer++;
- break;
- case DIFF_EQUAL:
- // Upon reaching an equality, check for prior redundancies.
- if (count_delete + count_insert > 1) {
- if (count_delete !== 0 && count_insert !== 0) {
- // Factor out any common prefixies.
- commonlength = diff_commonPrefix(text_insert, text_delete);
- if (commonlength !== 0) {
- if (
- pointer - count_delete - count_insert > 0 &&
- diffs[pointer - count_delete - count_insert - 1][0] ==
- DIFF_EQUAL
- ) {
- diffs[pointer - count_delete - count_insert - 1][1] +=
- text_insert.substring(0, commonlength);
- } else {
- diffs.splice(
- 0,
- 0,
- new Diff(DIFF_EQUAL, text_insert.substring(0, commonlength))
- );
- pointer++;
- }
- text_insert = text_insert.substring(commonlength);
- text_delete = text_delete.substring(commonlength);
- } // Factor out any common suffixies.
- commonlength = diff_commonSuffix(text_insert, text_delete);
- if (commonlength !== 0) {
- diffs[pointer][1] =
- text_insert.substring(text_insert.length - commonlength) +
- diffs[pointer][1];
- text_insert = text_insert.substring(
- 0,
- text_insert.length - commonlength
- );
- text_delete = text_delete.substring(
- 0,
- text_delete.length - commonlength
- );
- }
- } // Delete the offending records and add the merged ones.
- pointer -= count_delete + count_insert;
- diffs.splice(pointer, count_delete + count_insert);
- if (text_delete.length) {
- diffs.splice(pointer, 0, new Diff(DIFF_DELETE, text_delete));
- pointer++;
- }
- if (text_insert.length) {
- diffs.splice(pointer, 0, new Diff(DIFF_INSERT, text_insert));
- pointer++;
- }
- pointer++;
- } else if (pointer !== 0 && diffs[pointer - 1][0] == DIFF_EQUAL) {
- // Merge this equality with the previous one.
- diffs[pointer - 1][1] += diffs[pointer][1];
- diffs.splice(pointer, 1);
- } else {
- pointer++;
- }
- count_insert = 0;
- count_delete = 0;
- text_delete = '';
- text_insert = '';
- break;
- }
- }
- if (diffs[diffs.length - 1][1] === '') {
- diffs.pop(); // Remove the dummy entry at the end.
- } // Second pass: look for single edits surrounded on both sides by equalities
- // which can be shifted sideways to eliminate an equality.
- // e.g: A<ins>BA</ins>C -> <ins>AB</ins>AC
- var changes = false;
- pointer = 1; // Intentionally ignore the first and last element (don't need checking).
- while (pointer < diffs.length - 1) {
- if (
- diffs[pointer - 1][0] == DIFF_EQUAL &&
- diffs[pointer + 1][0] == DIFF_EQUAL
- ) {
- // This is a single edit surrounded by equalities.
- if (
- diffs[pointer][1].substring(
- diffs[pointer][1].length - diffs[pointer - 1][1].length
- ) == diffs[pointer - 1][1]
- ) {
- // Shift the edit over the previous equality.
- diffs[pointer][1] =
- diffs[pointer - 1][1] +
- diffs[pointer][1].substring(
- 0,
- diffs[pointer][1].length - diffs[pointer - 1][1].length
- );
- diffs[pointer + 1][1] = diffs[pointer - 1][1] + diffs[pointer + 1][1];
- diffs.splice(pointer - 1, 1);
- changes = true;
- } else if (
- diffs[pointer][1].substring(0, diffs[pointer + 1][1].length) ==
- diffs[pointer + 1][1]
- ) {
- // Shift the edit over the next equality.
- diffs[pointer - 1][1] += diffs[pointer + 1][1];
- diffs[pointer][1] =
- diffs[pointer][1].substring(diffs[pointer + 1][1].length) +
- diffs[pointer + 1][1];
- diffs.splice(pointer + 1, 1);
- changes = true;
- }
- }
- pointer++;
- } // If shifts were made, the diff needs reordering and another shift sweep.
- if (changes) {
- diff_cleanupMerge(diffs);
- }
- };
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