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commit bbbcadbec05dd3667059ad421c060f1b5d3d19bc 0 parents
Benjam�n Eidelman authored
11 .project
@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<projectDescription>
+ <name>jsondiffpatch</name>
+ <comment></comment>
+ <projects>
+ </projects>
+ <buildSpec>
+ </buildSpec>
+ <natures>
+ </natures>
+</projectDescription>
21 MIT-LICENSE.txt
@@ -0,0 +1,21 @@
+The MIT License
+
+Copyright (c) 2011 Benjam�n Eidelman twitter.com/beneidel
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
80 README.md
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+JsonDiffPatch
+=========
+
+*Diff & Patch for JavaScript objects and arrays (ie. any JSON serializable structure)*
+
+JsonDiffPatch is a small library that allows to diff to Javascript object trees, create a patch and apply it to update the original version.
+
+- Could be used for logging, audit, remote (client-server) synchronization of changes, etc.
+- Works in browsers and server (Node.js), use test/qunit.htm to test it in any browser/environment.
+- Automatically uses google diff_match_patch library for long texts when available (finds diff_match_patch global, other text diff libs can be plugged in)
+- Array can be diffed matching items by key, just provide add a "_key" property the array (in any of both versions). item position will be ignored.
+
+eg:
+
+ // sample data
+ var country = {
+ name: "Argentina",
+ capital: "Buenos Aires",
+ independence: new Date(1816, 6, 9),
+ unasur: true
+ };
+
+ // clone country, using dateReviver for Date objects
+ var country2 = JSON.parse(JSON.stringify(country),jsondiffpatch.dateReviver);
+
+ // make some changes
+ country2.name = "República Argentina";
+ country2.population = "41324992";
+ delete country2.capital;
+
+ var delta = jsondiffpatch.diff(country,country2);
+
+ /*
+ delta = {
+ "name":["Argentina","República Argentina"], // old value, new value
+ "population":["41324992"], // new value
+ "capital":["Buenos Aires",0,0] // deleted
+ }
+ */
+
+ // patch original
+ jsondiffpatch.patch(country, delta);
+
+ var delta2 = jsondiffpatch.diff(country,country2);
+ // delta2 is undefined, no difference
+
+For more complex cases (nested objects, arrays, long text diffs) check unit tests in /test/test.js
+
+---------------
+
+
+Targeted platforms
+----------------
+
+* All modern browsers, open test/qunit.htm in a browser to run unit tests.
+* Node.js
+
+[QUnit](http://docs.jquery.com/Qunit) is used for unit testing.
+Just open the [test page](http://benjamine.github.com/jsondiffpatch/test/qunit.htm) on your preferred browser.
+
+Including JsonDiffPatch in your application
+---------------
+
+Download the latest release from the web site (http://github.com/benjamine/jsondiffpatch) and copy
+`src/jsondiffpatch.js` to a suitable location. To support text diffs include Google's diff_match_patch,
+a version fixed to work in browsers as wall as in node.js is provided.
+
+Then include it in your HTML
+like so:
+
+ <script type="text/javascript" src="/path/to/jsondiffpatch.js"></script>
+ <script type="text/javascript" src="/path/to/diff_match_patch_uncompressed.js"></script>
+
+Note: you can use JsonDiffPatch on browserless JavaScript environments too (as [Node.js](http://nodejs.org/), or [Mozilla Rhino](http://www.mozilla.org/rhino/)).
+
+
+Running Unit Tests
+----------------
+
+Just open test/qunit.htm file on any browser, tests will be run on load.
2,162 src/diff_match_patch_uncompressed.js
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+/**
+ * Diff Match and Patch
+ *
+ * Copyright 2006 Google Inc.
+ * http://code.google.com/p/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)
+ */
+(function(){
+/**
+ * Class containing the diff, match and patch methods.
+ * @constructor
+ */
+function diff_match_patch() {
+
+ // Defaults.
+ // Redefine these in your program to override the defaults.
+
+ // Number of seconds to map a diff before giving up (0 for infinity).
+ this.Diff_Timeout = 1.0;
+ // Cost of an empty edit operation in terms of edit characters.
+ this.Diff_EditCost = 4;
+ // At what point is no match declared (0.0 = perfection, 1.0 = very loose).
+ this.Match_Threshold = 0.5;
+ // How far to search for a match (0 = exact location, 1000+ = broad match).
+ // A match this many characters away from the expected location will add
+ // 1.0 to the score (0.0 is a perfect match).
+ this.Match_Distance = 1000;
+ // When deleting a large block of text (over ~64 characters), how close does
+ // the contents have to match the expected contents. (0.0 = perfection,
+ // 1.0 = very loose). Note that Match_Threshold controls how closely the
+ // end points of a delete need to match.
+ this.Patch_DeleteThreshold = 0.5;
+ // Chunk size for context length.
+ this.Patch_Margin = 4;
+
+ // The number of bits in an int.
+ this.Match_MaxBits = 32;
+}
+
+
+// DIFF FUNCTIONS
+
+
+/**
+ * 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;
+var DIFF_INSERT = 1;
+var DIFF_EQUAL = 0;
+
+/** @typedef {!Array.<number|string>} */
+diff_match_patch.Diff;
+
+
+/**
+ * Find the differences between two texts. Simplifies the problem by stripping
+ * any common prefix or suffix off the texts before diffing.
+ * @param {string} text1 Old string to be diffed.
+ * @param {string} text2 New string to be diffed.
+ * @param {boolean=} opt_checklines Optional speedup flag. If present and false,
+ * then don't run a line-level diff first to identify the changed areas.
+ * Defaults to true, which does a faster, slightly less optimal diff.
+ * @param {number} opt_deadline Optional time when the diff should be complete
+ * by. Used internally for recursive calls. Users should set DiffTimeout
+ * instead.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ */
+diff_match_patch.prototype.diff_main = function(text1, text2, opt_checklines,
+ opt_deadline) {
+ // Set a deadline by which time the diff must be complete.
+ if (typeof opt_deadline == 'undefined') {
+ if (this.Diff_Timeout <= 0) {
+ opt_deadline = Number.MAX_VALUE;
+ } else {
+ opt_deadline = (new Date).getTime() + this.Diff_Timeout * 1000;
+ }
+ }
+ var deadline = opt_deadline;
+
+ // Check for null inputs.
+ if (text1 == null || text2 == null) {
+ throw new Error('Null input. (diff_main)');
+ }
+
+ // Check for equality (speedup).
+ if (text1 == text2) {
+ if (text1) {
+ return [[DIFF_EQUAL, text1]];
+ }
+ return [];
+ }
+
+ if (typeof opt_checklines == 'undefined') {
+ opt_checklines = true;
+ }
+ var checklines = opt_checklines;
+
+ // Trim off common prefix (speedup).
+ var commonlength = this.diff_commonPrefix(text1, text2);
+ var commonprefix = text1.substring(0, commonlength);
+ text1 = text1.substring(commonlength);
+ text2 = text2.substring(commonlength);
+
+ // Trim off common suffix (speedup).
+ commonlength = this.diff_commonSuffix(text1, text2);
+ var commonsuffix = text1.substring(text1.length - commonlength);
+ text1 = text1.substring(0, text1.length - commonlength);
+ text2 = text2.substring(0, text2.length - commonlength);
+
+ // Compute the diff on the middle block.
+ var diffs = this.diff_compute_(text1, text2, checklines, deadline);
+
+ // Restore the prefix and suffix.
+ if (commonprefix) {
+ diffs.unshift([DIFF_EQUAL, commonprefix]);
+ }
+ if (commonsuffix) {
+ diffs.push([DIFF_EQUAL, commonsuffix]);
+ }
+ this.diff_cleanupMerge(diffs);
+ return diffs;
+};
+
+
+/**
+ * Find the differences between two texts. Assumes that the texts do not
+ * have any common prefix or suffix.
+ * @param {string} text1 Old string to be diffed.
+ * @param {string} text2 New string to be diffed.
+ * @param {boolean} checklines Speedup flag. If false, then don't run a
+ * line-level diff first to identify the changed areas.
+ * If true, then run a faster, slightly less optimal diff.
+ * @param {number} deadline Time when the diff should be complete by.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ * @private
+ */
+diff_match_patch.prototype.diff_compute_ = function(text1, text2, checklines,
+ deadline) {
+ var diffs;
+
+ if (!text1) {
+ // Just add some text (speedup).
+ return [[DIFF_INSERT, text2]];
+ }
+
+ if (!text2) {
+ // Just delete some text (speedup).
+ return [[DIFF_DELETE, text1]];
+ }
+
+ var longtext = text1.length > text2.length ? text1 : text2;
+ var shorttext = text1.length > text2.length ? text2 : text1;
+ var i = longtext.indexOf(shorttext);
+ if (i != -1) {
+ // Shorter text is inside the longer text (speedup).
+ diffs = [[DIFF_INSERT, longtext.substring(0, i)],
+ [DIFF_EQUAL, shorttext],
+ [DIFF_INSERT, longtext.substring(i + shorttext.length)]];
+ // Swap insertions for deletions if diff is reversed.
+ if (text1.length > text2.length) {
+ diffs[0][0] = diffs[2][0] = DIFF_DELETE;
+ }
+ return diffs;
+ }
+
+ if (shorttext.length == 1) {
+ // Single character string.
+ // After the previous speedup, the character can't be an equality.
+ return [[DIFF_DELETE, text1], [DIFF_INSERT, text2]];
+ }
+ longtext = shorttext = null; // Garbage collect.
+
+ // Check to see if the problem can be split in two.
+ var hm = this.diff_halfMatch_(text1, text2);
+ if (hm) {
+ // A half-match was found, sort out the return data.
+ var text1_a = hm[0];
+ var text1_b = hm[1];
+ var text2_a = hm[2];
+ var text2_b = hm[3];
+ var mid_common = hm[4];
+ // Send both pairs off for separate processing.
+ var diffs_a = this.diff_main(text1_a, text2_a, checklines, deadline);
+ var diffs_b = this.diff_main(text1_b, text2_b, checklines, deadline);
+ // Merge the results.
+ return diffs_a.concat([[DIFF_EQUAL, mid_common]], diffs_b);
+ }
+
+ if (checklines && text1.length > 100 && text2.length > 100) {
+ return this.diff_lineMode_(text1, text2, deadline);
+ }
+
+ return this.diff_bisect_(text1, text2, deadline);
+};
+
+
+/**
+ * Do a quick line-level diff on both strings, then rediff the parts for
+ * greater accuracy.
+ * This speedup can produce non-minimal diffs.
+ * @param {string} text1 Old string to be diffed.
+ * @param {string} text2 New string to be diffed.
+ * @param {number} deadline Time when the diff should be complete by.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ * @private
+ */
+diff_match_patch.prototype.diff_lineMode_ = function(text1, text2, deadline) {
+ // Scan the text on a line-by-line basis first.
+ var a = this.diff_linesToChars_(text1, text2);
+ text1 = /** @type {string} */(a[0]);
+ text2 = /** @type {string} */(a[1]);
+ var linearray = /** @type {!Array.<string>} */(a[2]);
+
+ var diffs = this.diff_bisect_(text1, text2, deadline);
+
+ // Convert the diff back to original text.
+ this.diff_charsToLines_(diffs, linearray);
+ // Eliminate freak matches (e.g. blank lines)
+ this.diff_cleanupSemantic(diffs);
+
+ // Rediff any replacement blocks, this time character-by-character.
+ // Add a dummy entry at the end.
+ diffs.push([DIFF_EQUAL, '']);
+ var pointer = 0;
+ var count_delete = 0;
+ var count_insert = 0;
+ var text_delete = '';
+ var text_insert = '';
+ while (pointer < diffs.length) {
+ switch (diffs[pointer][0]) {
+ case DIFF_INSERT:
+ count_insert++;
+ text_insert += diffs[pointer][1];
+ break;
+ case DIFF_DELETE:
+ count_delete++;
+ text_delete += diffs[pointer][1];
+ break;
+ case DIFF_EQUAL:
+ // Upon reaching an equality, check for prior redundancies.
+ if (count_delete >= 1 && count_insert >= 1) {
+ // Delete the offending records and add the merged ones.
+ var a = this.diff_main(text_delete, text_insert, false, deadline);
+ diffs.splice(pointer - count_delete - count_insert,
+ count_delete + count_insert);
+ pointer = pointer - count_delete - count_insert;
+ for (var j = a.length - 1; j >= 0; j--) {
+ diffs.splice(pointer, 0, a[j]);
+ }
+ pointer = pointer + a.length;
+ }
+ count_insert = 0;
+ count_delete = 0;
+ text_delete = '';
+ text_insert = '';
+ break;
+ }
+ pointer++;
+ }
+ diffs.pop(); // Remove the dummy entry at the end.
+
+ return diffs;
+};
+
+
+/**
+ * Find the 'middle snake' of a diff, split the problem in two
+ * and return the recursively constructed diff.
+ * See Myers 1986 paper: An O(ND) Difference Algorithm and Its Variations.
+ * @param {string} text1 Old string to be diffed.
+ * @param {string} text2 New string to be diffed.
+ * @param {number} deadline Time at which to bail if not yet complete.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ * @private
+ */
+diff_match_patch.prototype.diff_bisect_ = function(text1, text2, deadline) {
+ // Cache the text lengths to prevent multiple calls.
+ var text1_length = text1.length;
+ var text2_length = text2.length;
+ var max_d = Math.ceil((text1_length + text2_length) / 2);
+ var v_offset = max_d;
+ var v_length = 2 * max_d;
+ var v1 = new Array(v_length);
+ var v2 = new Array(v_length);
+ // Setting all elements to -1 is faster in Chrome & Firefox than mixing
+ // integers and undefined.
+ for (var x = 0; x < v_length; x++) {
+ v1[x] = -1;
+ v2[x] = -1;
+ }
+ v1[v_offset + 1] = 0;
+ v2[v_offset + 1] = 0;
+ var delta = text1_length - text2_length;
+ // If the total number of characters is odd, then the front path will collide
+ // with the reverse path.
+ var front = (delta % 2 != 0);
+ // Offsets for start and end of k loop.
+ // Prevents mapping of space beyond the grid.
+ var k1start = 0;
+ var k1end = 0;
+ var k2start = 0;
+ var k2end = 0;
+ for (var d = 0; d < max_d; d++) {
+ // Bail out if deadline is reached.
+ if ((new Date()).getTime() > deadline) {
+ break;
+ }
+
+ // Walk the front path one step.
+ for (var k1 = -d + k1start; k1 <= d - k1end; k1 += 2) {
+ var k1_offset = v_offset + k1;
+ var x1;
+ if (k1 == -d || k1 != d && v1[k1_offset - 1] < v1[k1_offset + 1]) {
+ x1 = v1[k1_offset + 1];
+ } else {
+ x1 = v1[k1_offset - 1] + 1;
+ }
+ var y1 = x1 - k1;
+ while (x1 < text1_length && y1 < text2_length &&
+ text1.charAt(x1) == text2.charAt(y1)) {
+ x1++;
+ y1++;
+ }
+ v1[k1_offset] = x1;
+ if (x1 > text1_length) {
+ // Ran off the right of the graph.
+ k1end += 2;
+ } else if (y1 > text2_length) {
+ // Ran off the bottom of the graph.
+ k1start += 2;
+ } else if (front) {
+ var k2_offset = v_offset + delta - k1;
+ if (k2_offset >= 0 && k2_offset < v_length && v2[k2_offset] != -1) {
+ // Mirror x2 onto top-left coordinate system.
+ var x2 = text1_length - v2[k2_offset];
+ if (x1 >= x2) {
+ // Overlap detected.
+ return this.diff_bisectSplit_(text1, text2, x1, y1, deadline);
+ }
+ }
+ }
+ }
+
+ // Walk the reverse path one step.
+ for (var k2 = -d + k2start; k2 <= d - k2end; k2 += 2) {
+ var k2_offset = v_offset + k2;
+ var x2;
+ if (k2 == -d || k2 != d && v2[k2_offset - 1] < v2[k2_offset + 1]) {
+ x2 = v2[k2_offset + 1];
+ } else {
+ x2 = v2[k2_offset - 1] + 1;
+ }
+ var y2 = x2 - k2;
+ while (x2 < text1_length && y2 < text2_length &&
+ text1.charAt(text1_length - x2 - 1) ==
+ text2.charAt(text2_length - y2 - 1)) {
+ x2++;
+ y2++;
+ }
+ v2[k2_offset] = x2;
+ if (x2 > text1_length) {
+ // Ran off the left of the graph.
+ k2end += 2;
+ } else if (y2 > text2_length) {
+ // Ran off the top of the graph.
+ k2start += 2;
+ } else if (!front) {
+ var k1_offset = v_offset + delta - k2;
+ if (k1_offset >= 0 && k1_offset < v_length && v1[k1_offset] != -1) {
+ var x1 = v1[k1_offset];
+ var y1 = v_offset + x1 - k1_offset;
+ // Mirror x2 onto top-left coordinate system.
+ x2 = text1_length - x2;
+ if (x1 >= x2) {
+ // Overlap detected.
+ return this.diff_bisectSplit_(text1, text2, x1, y1, deadline);
+ }
+ }
+ }
+ }
+ }
+ // Diff took too long and hit the deadline or
+ // number of diffs equals number of characters, no commonality at all.
+ return [[DIFF_DELETE, text1], [DIFF_INSERT, text2]];
+};
+
+
+/**
+ * Given the location of the 'middle snake', split the diff in two parts
+ * and recurse.
+ * @param {string} text1 Old string to be diffed.
+ * @param {string} text2 New string to be diffed.
+ * @param {number} x Index of split point in text1.
+ * @param {number} y Index of split point in text2.
+ * @param {number} deadline Time at which to bail if not yet complete.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ * @private
+ */
+diff_match_patch.prototype.diff_bisectSplit_ = function(text1, text2, x, y,
+ deadline) {
+ var text1a = text1.substring(0, x);
+ var text2a = text2.substring(0, y);
+ var text1b = text1.substring(x);
+ var text2b = text2.substring(y);
+
+ // Compute both diffs serially.
+ var diffs = this.diff_main(text1a, text2a, false, deadline);
+ var diffsb = this.diff_main(text1b, text2b, false, deadline);
+
+ return diffs.concat(diffsb);
+};
+
+
+/**
+ * Split two texts into an array of strings. Reduce the texts to a string of
+ * hashes where each Unicode character represents one line.
+ * @param {string} text1 First string.
+ * @param {string} text2 Second string.
+ * @return {!Array.<string|!Array.<string>>} Three element Array, containing the
+ * encoded text1, the encoded text2 and the array of unique strings. The
+ * zeroth element of the array of unique strings is intentionally blank.
+ * @private
+ */
+diff_match_patch.prototype.diff_linesToChars_ = function(text1, text2) {
+ var lineArray = []; // e.g. lineArray[4] == 'Hello\n'
+ var lineHash = {}; // e.g. lineHash['Hello\n'] == 4
+
+ // '\x00' is a valid character, but various debuggers don't like it.
+ // So we'll insert a junk entry to avoid generating a null character.
+ lineArray[0] = '';
+
+ /**
+ * Split a text into an array of strings. Reduce the texts to a string of
+ * hashes where each Unicode character represents one line.
+ * Modifies linearray and linehash through being a closure.
+ * @param {string} text String to encode.
+ * @return {string} Encoded string.
+ * @private
+ */
+ function diff_linesToCharsMunge_(text) {
+ var chars = '';
+ // Walk the text, pulling out a substring for each line.
+ // text.split('\n') would would temporarily double our memory footprint.
+ // Modifying text would create many large strings to garbage collect.
+ var lineStart = 0;
+ var lineEnd = -1;
+ // Keeping our own length variable is faster than looking it up.
+ var lineArrayLength = lineArray.length;
+ while (lineEnd < text.length - 1) {
+ lineEnd = text.indexOf('\n', lineStart);
+ if (lineEnd == -1) {
+ lineEnd = text.length - 1;
+ }
+ var line = text.substring(lineStart, lineEnd + 1);
+ lineStart = lineEnd + 1;
+
+ if (lineHash.hasOwnProperty ? lineHash.hasOwnProperty(line) :
+ (lineHash[line] !== undefined)) {
+ chars += String.fromCharCode(lineHash[line]);
+ } else {
+ chars += String.fromCharCode(lineArrayLength);
+ lineHash[line] = lineArrayLength;
+ lineArray[lineArrayLength++] = line;
+ }
+ }
+ return chars;
+ }
+
+ var chars1 = diff_linesToCharsMunge_(text1);
+ var chars2 = diff_linesToCharsMunge_(text2);
+ return [chars1, chars2, lineArray];
+};
+
+
+/**
+ * Rehydrate the text in a diff from a string of line hashes to real lines of
+ * text.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @param {!Array.<string>} lineArray Array of unique strings.
+ * @private
+ */
+diff_match_patch.prototype.diff_charsToLines_ = function(diffs, lineArray) {
+ for (var x = 0; x < diffs.length; x++) {
+ var chars = diffs[x][1];
+ var text = [];
+ for (var y = 0; y < chars.length; y++) {
+ text[y] = lineArray[chars.charCodeAt(y)];
+ }
+ diffs[x][1] = text.join('');
+ }
+};
+
+
+/**
+ * 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.
+ */
+diff_match_patch.prototype.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: http://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.
+ */
+diff_match_patch.prototype.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: http://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
+ */
+diff_match_patch.prototype.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: http://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++;
+ }
+ }
+};
+
+
+/**
+ * Do the two texts share a substring which is at least half the length of the
+ * longer text?
+ * This speedup can produce non-minimal diffs.
+ * @param {string} text1 First string.
+ * @param {string} text2 Second string.
+ * @return {Array.<string>} Five element Array, containing the prefix of
+ * text1, the suffix of text1, the prefix of text2, the suffix of
+ * text2 and the common middle. Or null if there was no match.
+ * @private
+ */
+diff_match_patch.prototype.diff_halfMatch_ = function(text1, text2) {
+ if (this.Diff_Timeout <= 0) {
+ // Don't risk returning a non-optimal diff if we have unlimited time.
+ return null;
+ }
+ var longtext = text1.length > text2.length ? text1 : text2;
+ var shorttext = text1.length > text2.length ? text2 : text1;
+ if (longtext.length < 4 || shorttext.length * 2 < longtext.length) {
+ return null; // Pointless.
+ }
+ var dmp = this; // 'this' becomes 'window' in a closure.
+
+ /**
+ * Does a substring of shorttext exist within longtext such that the substring
+ * is at least half the length of longtext?
+ * Closure, but does not reference any external variables.
+ * @param {string} longtext Longer string.
+ * @param {string} shorttext Shorter string.
+ * @param {number} i Start index of quarter length substring within longtext.
+ * @return {Array.<string>} Five element Array, containing the prefix of
+ * longtext, the suffix of longtext, the prefix of shorttext, the suffix
+ * of shorttext and the common middle. Or null if there was no match.
+ * @private
+ */
+ function diff_halfMatchI_(longtext, shorttext, i) {
+ // Start with a 1/4 length substring at position i as a seed.
+ var seed = longtext.substring(i, i + Math.floor(longtext.length / 4));
+ var j = -1;
+ var best_common = '';
+ var best_longtext_a, best_longtext_b, best_shorttext_a, best_shorttext_b;
+ while ((j = shorttext.indexOf(seed, j + 1)) != -1) {
+ var prefixLength = dmp.diff_commonPrefix(longtext.substring(i),
+ shorttext.substring(j));
+ var suffixLength = dmp.diff_commonSuffix(longtext.substring(0, i),
+ shorttext.substring(0, j));
+ if (best_common.length < suffixLength + prefixLength) {
+ best_common = shorttext.substring(j - suffixLength, j) +
+ shorttext.substring(j, j + prefixLength);
+ best_longtext_a = longtext.substring(0, i - suffixLength);
+ best_longtext_b = longtext.substring(i + prefixLength);
+ best_shorttext_a = shorttext.substring(0, j - suffixLength);
+ best_shorttext_b = shorttext.substring(j + prefixLength);
+ }
+ }
+ if (best_common.length * 2 >= longtext.length) {
+ return [best_longtext_a, best_longtext_b,
+ best_shorttext_a, best_shorttext_b, best_common];
+ } else {
+ return null;
+ }
+ }
+
+ // First check if the second quarter is the seed for a half-match.
+ var hm1 = diff_halfMatchI_(longtext, shorttext,
+ Math.ceil(longtext.length / 4));
+ // Check again based on the third quarter.
+ var hm2 = diff_halfMatchI_(longtext, shorttext,
+ Math.ceil(longtext.length / 2));
+ var hm;
+ if (!hm1 && !hm2) {
+ return null;
+ } else if (!hm2) {
+ hm = hm1;
+ } else if (!hm1) {
+ hm = hm2;
+ } else {
+ // Both matched. Select the longest.
+ hm = hm1[4].length > hm2[4].length ? hm1 : hm2;
+ }
+
+ // A half-match was found, sort out the return data.
+ var text1_a, text1_b, text2_a, text2_b;
+ if (text1.length > text2.length) {
+ text1_a = hm[0];
+ text1_b = hm[1];
+ text2_a = hm[2];
+ text2_b = hm[3];
+ } else {
+ text2_a = hm[0];
+ text2_b = hm[1];
+ text1_a = hm[2];
+ text1_b = hm[3];
+ }
+ var mid_common = hm[4];
+ return [text1_a, text1_b, text2_a, text2_b, mid_common];
+};
+
+
+/**
+ * Reduce the number of edits by eliminating semantically trivial equalities.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ */
+diff_match_patch.prototype.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 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 = /** @type {string} */(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 !== null && (lastequality.length <=
+ Math.max(length_insertions1, length_deletions1)) &&
+ (lastequality.length <= Math.max(length_insertions2,
+ length_deletions2))) {
+ // Duplicate record.
+ diffs.splice(equalities[equalitiesLength - 1], 0,
+ [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) {
+ this.diff_cleanupMerge(diffs);
+ }
+ this.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>
+ // 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 = /** @type {string} */(diffs[pointer - 1][1]);
+ var insertion = /** @type {string} */(diffs[pointer][1]);
+ var overlap_length = this.diff_commonOverlap_(deletion, insertion);
+ if (overlap_length >= deletion.length / 2 ||
+ overlap_length >= insertion.length / 2) {
+ // Overlap found. Insert an equality and trim the surrounding edits.
+ diffs.splice(pointer, 0,
+ [DIFF_EQUAL, insertion.substring(0, overlap_length)]);
+ diffs[pointer - 1][1] =
+ deletion.substring(0, deletion.length - overlap_length);
+ diffs[pointer + 1][1] = insertion.substring(overlap_length);
+ 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.
+ */
+diff_match_patch.prototype.diff_cleanupSemanticLossless = function(diffs) {
+ // Define some regex patterns for matching boundaries.
+ var punctuation = /[^a-zA-Z0-9]/;
+ var whitespace = /\s/;
+ var linebreak = /[\r\n]/;
+ var blanklineEnd = /\n\r?\n$/;
+ var blanklineStart = /^\r?\n\r?\n/;
+
+ /**
+ * Given two strings, compute a score representing whether the internal
+ * boundary falls on logical boundaries.
+ * Scores range from 5 (best) to 0 (worst).
+ * Closure, makes reference to regex patterns defined above.
+ * @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 5;
+ }
+
+ // 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 score = 0;
+ // One point for non-alphanumeric.
+ if (one.charAt(one.length - 1).match(punctuation) ||
+ two.charAt(0).match(punctuation)) {
+ score++;
+ // Two points for whitespace.
+ if (one.charAt(one.length - 1).match(whitespace) ||
+ two.charAt(0).match(whitespace)) {
+ score++;
+ // Three points for line breaks.
+ if (one.charAt(one.length - 1).match(linebreak) ||
+ two.charAt(0).match(linebreak)) {
+ score++;
+ // Four points for blank lines.
+ if (one.match(blanklineEnd) || two.match(blanklineStart)) {
+ score++;
+ }
+ }
+ }
+ }
+ return score;
+ }
+
+ 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 = /** @type {string} */(diffs[pointer - 1][1]);
+ var edit = /** @type {string} */(diffs[pointer][1]);
+ var equality2 = /** @type {string} */(diffs[pointer + 1][1]);
+
+ // First, shift the edit as far left as possible.
+ var commonOffset = this.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++;
+ }
+};
+
+
+/**
+ * Reduce the number of edits by eliminating operationally trivial equalities.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ */
+diff_match_patch.prototype.diff_cleanupEfficiency = 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.
+ var lastequality = ''; // Always equal to equalities[equalitiesLength-1][1]
+ var pointer = 0; // Index of current position.
+ // Is there an insertion operation before the last equality.
+ var pre_ins = false;
+ // Is there a deletion operation before the last equality.
+ var pre_del = false;
+ // Is there an insertion operation after the last equality.
+ var post_ins = false;
+ // Is there a deletion operation after the last equality.
+ var post_del = false;
+ while (pointer < diffs.length) {
+ if (diffs[pointer][0] == DIFF_EQUAL) { // Equality found.
+ if (diffs[pointer][1].length < this.Diff_EditCost &&
+ (post_ins || post_del)) {
+ // Candidate found.
+ equalities[equalitiesLength++] = pointer;
+ pre_ins = post_ins;
+ pre_del = post_del;
+ lastequality = diffs[pointer][1];
+ } else {
+ // Not a candidate, and can never become one.
+ equalitiesLength = 0;
+ lastequality = '';
+ }
+ post_ins = post_del = false;
+ } else { // An insertion or deletion.
+ if (diffs[pointer][0] == DIFF_DELETE) {
+ post_del = true;
+ } else {
+ post_ins = true;
+ }
+ /*
+ * Five types to be split:
+ * <ins>A</ins><del>B</del>XY<ins>C</ins><del>D</del>
+ * <ins>A</ins>X<ins>C</ins><del>D</del>
+ * <ins>A</ins><del>B</del>X<ins>C</ins>
+ * <ins>A</del>X<ins>C</ins><del>D</del>
+ * <ins>A</ins><del>B</del>X<del>C</del>
+ */
+ if (lastequality && ((pre_ins && pre_del && post_ins && post_del) ||
+ ((lastequality.length < this.Diff_EditCost / 2) &&
+ (pre_ins + pre_del + post_ins + post_del) == 3))) {
+ // Duplicate record.
+ diffs.splice(equalities[equalitiesLength - 1], 0,
+ [DIFF_DELETE, lastequality]);
+ // Change second copy to insert.
+ diffs[equalities[equalitiesLength - 1] + 1][0] = DIFF_INSERT;
+ equalitiesLength--; // Throw away the equality we just deleted;
+ lastequality = '';
+ if (pre_ins && pre_del) {
+ // No changes made which could affect previous entry, keep going.
+ post_ins = post_del = true;
+ equalitiesLength = 0;
+ } else {
+ equalitiesLength--; // Throw away the previous equality.
+ pointer = equalitiesLength > 0 ?
+ equalities[equalitiesLength - 1] : -1;
+ post_ins = post_del = false;
+ }
+ changes = true;
+ }
+ }
+ pointer++;
+ }
+
+ if (changes) {
+ this.diff_cleanupMerge(diffs);
+ }
+};
+
+
+/**
+ * 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.
+ */
+diff_match_patch.prototype.diff_cleanupMerge = function(diffs) {
+ diffs.push([DIFF_EQUAL, '']); // Add a dummy entry at the end.
+ 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 = this.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, [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 = this.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.
+ if (count_delete === 0) {
+ diffs.splice(pointer - count_delete - count_insert,
+ count_delete + count_insert, [DIFF_INSERT, text_insert]);
+ } else if (count_insert === 0) {
+ diffs.splice(pointer - count_delete - count_insert,
+ count_delete + count_insert, [DIFF_DELETE, text_delete]);
+ } else {
+ diffs.splice(pointer - count_delete - count_insert,
+ count_delete + count_insert, [DIFF_DELETE, text_delete],
+ [DIFF_INSERT, text_insert]);
+ }
+ pointer = pointer - count_delete - count_insert +
+ (count_delete ? 1 : 0) + (count_insert ? 1 : 0) + 1;
+ } 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) {
+ this.diff_cleanupMerge(diffs);
+ }
+};
+
+
+/**
+ * loc is a location in text1, compute and return the equivalent location in
+ * text2.
+ * e.g. 'The cat' vs 'The big cat', 1->1, 5->8
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @param {number} loc Location within text1.
+ * @return {number} Location within text2.
+ */
+diff_match_patch.prototype.diff_xIndex = function(diffs, loc) {
+ var chars1 = 0;
+ var chars2 = 0;
+ var last_chars1 = 0;
+ var last_chars2 = 0;
+ var x;
+ for (x = 0; x < diffs.length; x++) {
+ if (diffs[x][0] !== DIFF_INSERT) { // Equality or deletion.
+ chars1 += diffs[x][1].length;
+ }
+ if (diffs[x][0] !== DIFF_DELETE) { // Equality or insertion.
+ chars2 += diffs[x][1].length;
+ }
+ if (chars1 > loc) { // Overshot the location.
+ break;
+ }
+ last_chars1 = chars1;
+ last_chars2 = chars2;
+ }
+ // Was the location was deleted?
+ if (diffs.length != x && diffs[x][0] === DIFF_DELETE) {
+ return last_chars2;
+ }
+ // Add the remaining character length.
+ return last_chars2 + (loc - last_chars1);
+};
+
+
+/**
+ * Convert a diff array into a pretty HTML report.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @return {string} HTML representation.
+ */
+diff_match_patch.prototype.diff_prettyHtml = function(diffs) {
+ var html = [];
+ var i = 0;
+ var pattern_amp = /&/g;
+ var pattern_lt = /</g;
+ var pattern_gt = />/g;
+ var pattern_para = /\n/g;
+ for (var x = 0; x < diffs.length; x++) {
+ var op = diffs[x][0]; // Operation (insert, delete, equal)
+ var data = diffs[x][1]; // Text of change.
+ var text = data.replace(pattern_amp, '&amp;').replace(pattern_lt, '&lt;')
+ .replace(pattern_gt, '&gt;').replace(pattern_para, '&para;<br>');
+ switch (op) {
+ case DIFF_INSERT:
+ html[x] = '<ins style="background:#e6ffe6;">' + text + '</ins>';
+ break;
+ case DIFF_DELETE:
+ html[x] = '<del style="background:#ffe6e6;">' + text + '</del>';
+ break;
+ case DIFF_EQUAL:
+ html[x] = '<span>' + text + '</span>';
+ break;
+ }
+ if (op !== DIFF_DELETE) {
+ i += data.length;
+ }
+ }
+ return html.join('');
+};
+
+
+/**
+ * Compute and return the source text (all equalities and deletions).
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @return {string} Source text.
+ */
+diff_match_patch.prototype.diff_text1 = function(diffs) {
+ var text = [];
+ for (var x = 0; x < diffs.length; x++) {
+ if (diffs[x][0] !== DIFF_INSERT) {
+ text[x] = diffs[x][1];
+ }
+ }
+ return text.join('');
+};
+
+
+/**
+ * Compute and return the destination text (all equalities and insertions).
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @return {string} Destination text.
+ */
+diff_match_patch.prototype.diff_text2 = function(diffs) {
+ var text = [];
+ for (var x = 0; x < diffs.length; x++) {
+ if (diffs[x][0] !== DIFF_DELETE) {
+ text[x] = diffs[x][1];
+ }
+ }
+ return text.join('');
+};
+
+
+/**
+ * Compute the Levenshtein distance; the number of inserted, deleted or
+ * substituted characters.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @return {number} Number of changes.
+ */
+diff_match_patch.prototype.diff_levenshtein = function(diffs) {
+ var levenshtein = 0;
+ var insertions = 0;
+ var deletions = 0;
+ for (var x = 0; x < diffs.length; x++) {
+ var op = diffs[x][0];
+ var data = diffs[x][1];
+ switch (op) {
+ case DIFF_INSERT:
+ insertions += data.length;
+ break;
+ case DIFF_DELETE:
+ deletions += data.length;
+ break;
+ case DIFF_EQUAL:
+ // A deletion and an insertion is one substitution.
+ levenshtein += Math.max(insertions, deletions);
+ insertions = 0;
+ deletions = 0;
+ break;
+ }
+ }
+ levenshtein += Math.max(insertions, deletions);
+ return levenshtein;
+};
+
+
+/**
+ * Crush the diff into an encoded string which describes the operations
+ * required to transform text1 into text2.
+ * E.g. =3\t-2\t+ing -> Keep 3 chars, delete 2 chars, insert 'ing'.
+ * Operations are tab-separated. Inserted text is escaped using %xx notation.
+ * @param {!Array.<!diff_match_patch.Diff>} diffs Array of diff tuples.
+ * @return {string} Delta text.
+ */
+diff_match_patch.prototype.diff_toDelta = function(diffs) {
+ var text = [];
+ for (var x = 0; x < diffs.length; x++) {
+ switch (diffs[x][0]) {
+ case DIFF_INSERT:
+ text[x] = '+' + encodeURI(diffs[x][1]);
+ break;
+ case DIFF_DELETE:
+ text[x] = '-' + diffs[x][1].length;
+ break;
+ case DIFF_EQUAL:
+ text[x] = '=' + diffs[x][1].length;
+ break;
+ }
+ }
+ return text.join('\t').replace(/%20/g, ' ');
+};
+
+
+/**
+ * Given the original text1, and an encoded string which describes the
+ * operations required to transform text1 into text2, compute the full diff.
+ * @param {string} text1 Source string for the diff.
+ * @param {string} delta Delta text.
+ * @return {!Array.<!diff_match_patch.Diff>} Array of diff tuples.
+ * @throws {!Error} If invalid input.
+ */
+diff_match_patch.prototype.diff_fromDelta = function(text1, delta) {
+ var diffs = [];
+ var diffsLength = 0; // Keeping our own length var is faster in JS.
+ var pointer = 0; // Cursor in text1
+ var tokens = delta.split(/\t/g);
+ for (var x = 0; x < tokens.length; x++) {
+ // Each token begins with a one character parameter which specifies the
+ // operation of this token (delete, insert, equality).
+ var param = tokens[x].substring(1);
+ switch (tokens[x].charAt(0)) {
+ case '+':
+ try {
+ diffs[diffsLength++] = [DIFF_INSERT, decodeURI(param)];
+ } catch (ex) {
+ // Malformed URI sequence.
+ throw new Error('Illegal escape in diff_fromDelta: ' + param);
+ }
+ break;
+ case '-':
+ // Fall through.
+ case '=':
+ var n = parseInt(param, 10);
+ if (isNaN(n) || n < 0) {
+ throw new Error('Invalid number in diff_fromDelta: ' + param);
+ }
+ var text = text1.substring(pointer, pointer += n);
+ if (tokens[x].charAt(0) == '=') {
+ diffs[diffsLength++] = [DIFF_EQUAL, text];
+ } else {
+ diffs[diffsLength++] = [DIFF_DELETE, text];
+ }
+ break;
+ default:
+ // Blank tokens are ok (from a trailing \t).
+ // Anything else is an error.
+ if (tokens[x]) {
+ throw new Error('Invalid diff operation in diff_fromDelta: ' +
+ tokens[x]);
+ }
+ }
+ }
+ if (pointer != text1.length) {
+ throw new Error('Delta length (' + pointer +
+ ') does not equal source text length (' + text1.length + ').');
+ }
+ return diffs;
+};
+
+
+// MATCH FUNCTIONS
+
+
+/**
+ * Locate the best instance of 'pattern' in 'text' near 'loc'.
+ * @param {string} text The text to search.
+ * @param {string} pattern The pattern to search for.
+ * @param {number} loc The location to search around.
+ * @return {number} Best match index or -1.
+ */
+diff_match_patch.prototype.match_main = function(text, pattern, loc) {
+ // Check for null inputs.
+ if (text == null || pattern == null || loc == null) {
+ throw new Error('Null input. (match_main)');
+ }
+
+ loc = Math.max(0, Math.min(loc, text.length));
+ if (text == pattern) {
+ // Shortcut (potentially not guaranteed by the algorithm)
+ return 0;
+ } else if (!text.length) {
+ // Nothing to match.
+ return -1;
+ } else if (text.substring(loc, loc + pattern.length) == pattern) {
+ // Perfect match at the perfect spot! (Includes case of null pattern)
+ return loc;
+ } else {
+ // Do a fuzzy compare.
+ return this.match_bitap_(text, pattern, loc);
+ }
+};
+
+
+/**
+ * Locate the best instance of 'pattern' in 'text' near 'loc' using the
+ * Bitap algorithm.
+ * @param {string} text The text to search.
+ * @param {string} pattern The pattern to search for.
+ * @param {number} loc The location to search around.
+ * @return {number} Best match index or -1.
+ * @private
+ */
+diff_match_patch.prototype.match_bitap_ = function(text, pattern, loc) {
+ if (pattern.length > this.Match_MaxBits) {
+ throw new Error('Pattern too long for this browser.');
+ }
+
+ // Initialise the alphabet.
+ var s = this.match_alphabet_(pattern);
+
+ var dmp = this; // 'this' becomes 'window' in a closure.
+
+ /**
+ * Compute and return the score for a match with e errors and x location.
+ * Accesses loc and pattern through being a closure.
+ * @param {number} e Number of errors in match.
+ * @param {number} x Location of match.
+ * @return {number} Overall score for match (0.0 = good, 1.0 = bad).
+ * @private
+ */
+ function match_bitapScore_(e, x) {
+ var accuracy = e / pattern.length;
+ var proximity = Math.abs(loc - x);
+ if (!dmp.Match_Distance) {
+ // Dodge divide by zero error.
+ return proximity ? 1.0 : accuracy;
+ }
+ return accuracy + (proximity / dmp.Match_Distance);
+ }
+
+ // Highest score beyond which we give up.
+ var score_threshold = this.Match_Threshold;
+ // Is there a nearby exact match? (speedup)
+ var best_loc = text.indexOf(pattern, loc);
+ if (best_loc != -1) {
+ score_threshold = Math.min(match_bitapScore_(0, best_loc), score_threshold);
+ // What about in the other direction? (speedup)
+ best_loc = text.lastIndexOf(pattern, loc + pattern.length);
+ if (best_loc != -1) {
+ score_threshold =
+ Math.min(match_bitapScore_(0, best_loc), score_threshold);
+ }
+ }
+
+ // Initialise the bit arrays.
+ var matchmask = 1 << (pattern.length - 1);
+ best_loc = -1;
+
+ var bin_min, bin_mid;
+ var bin_max = pattern.length + text.length;
+ var last_rd;
+ for (var d = 0; d < pattern.length; d++) {
+ // Scan for the best match; each iteration allows for one more error.
+ // Run a binary search to determine how far from 'loc' we can stray at this
+ // error level.
+ bin_min = 0;
+ bin_mid = bin_max;
+ while (bin_min < bin_mid) {
+ if (match_bitapScore_(d, loc + bin_mid) <= score_threshold) {
+ bin_min = bin_mid;
+ } else {
+ bin_max = bin_mid;
+ }
+ bin_mid = Math.floor((bin_max - bin_min) / 2 + bin_min);
+ }
+ // Use the result from this iteration as the maximum for the next.
+ bin_max = bin_mid;
+ var start = Math.max(1, loc - bin_mid + 1);
+ var finish = Math.min(loc + bin_mid, text.length) + pattern.length;
+
+ var rd = Array(finish + 2);
+ rd[finish + 1] = (1 << d) - 1;
+ for (var j = finish; j >= start; j--) {
+ // The alphabet (s) is a sparse hash, so the following line generates
+ // warnings.
+ var charMatch = s[text.charAt(j - 1)];
+ if (d === 0) { // First pass: exact match.
+ rd[j] = ((rd[j + 1] << 1) | 1) & charMatch;
+ } else { // Subsequent passes: fuzzy match.
+ rd[j] = ((rd[j + 1] << 1) | 1) & charMatch |
+ (((last_rd[j + 1] | last_rd[j]) << 1) | 1) |
+ last_rd[j + 1];
+ }
+ if (rd[j] & matchmask) {
+ var score = match_bitapScore_(d, j - 1);
+ // This match will almost certainly be better than any existing match.
+ // But check anyway.
+ if (score <= score_threshold) {
+ // Told you so.
+ score_threshold = score;
+ best_loc = j - 1;
+ if (best_loc > loc) {
+ // When passing loc, don't exceed our current distance from loc.
+ start = Math.max(1, 2 * loc - best_loc);
+ } else {
+ // Already passed loc, downhill from here on in.
+ break;
+ }
+ }
+ }
+ }
+ // No hope for a (better) match at greater error levels.
+ if (match_bitapScore_(d + 1, loc) > score_threshold) {
+ break;
+ }
+ last_rd = rd;
+ }
+ return best_loc;
+};
+
+
+/**
+ * Initialise the alphabet for the Bitap algorithm.
+ * @param {string} pattern The text to encode.
+ * @return {!Object} Hash of character locations.
+ * @private
+ */
+diff_match_patch.prototype.match_alphabet_ = function(pattern) {
+ var s = {};
+ for (var i = 0; i < pattern.length; i++) {
+ s[pattern.charAt(i)] = 0;
+ }
+ for (var i = 0; i < pattern.length; i++) {
+ s[pattern.charAt(i)] |= 1 << (pattern.length - i - 1);
+ }
+ return s;
+};
+
+
+// PATCH FUNCTIONS
+
+
+/**
+ * Increase the context until it is unique,
+ * but don't let the pattern expand beyond Match_MaxBits.
+ * @param {!diff_match_patch.patch_obj} patch The patch to grow.
+ * @param {string} text Source text.
+ * @private
+ */
+diff_match_patch.prototype.patch_addContext_ = function(patch, text) {
+ if (text.length == 0) {
+ return;
+ }
+ var pattern = text.substring(patch.start2, patch.start2 + patch.length1);
+ var padding = 0;
+
+ // Look for the first and last matches of pattern in text. If two different
+ // matches are found, increase the pattern length.
+ while (text.indexOf(pattern) != text.lastIndexOf(pattern) &&
+ pattern.length < this.Match_MaxBits - this.Patch_Margin -
+ this.Patch_Margin) {
+ padding += this.Patch_Margin;
+ pattern = text.substring(patch.start2 - padding,
+ patch.start2 + patch.length1 + padding);
+ }
+ // Add one chunk for good luck.
+ padding += this.Patch_Margin;
+
+ // Add the prefix.
+ var prefix = text.substring(patch.start2 - padding, patch.start2);
+ if (prefix) {
+ patch.diffs.unshift([DIFF_EQUAL, prefix]);
+ }
+ // Add the suffix.
+ var suffix = text.substring(patch.start2 + patch.length1,
+ patch.start2 + patch.length1 + padding);
+ if (suffix) {
+ patch.diffs.push([DIFF_EQUAL, suffix]);
+ }
+
+ // Roll back the start points.
+ patch.start1 -= prefix.length;
+ patch.start2 -= prefix.length;
+ // Extend the lengths.
+ patch.length1 += prefix.length + suffix.length;
+ patch.length2 += prefix.length + suffix.length;
+};
+
+
+/**
+ * Compute a list of patches to turn text1 into text2.
+ * Use diffs if provided, otherwise compute it ourselves.
+ * There are four ways to call this function, depending on what data is
+ * available to the caller:
+ * Method 1:
+ * a = text1, b = text2
+ * Method 2:
+ * a = diffs
+ * Method 3 (optimal):
+ * a = text1, b = diffs
+ * Method 4 (deprecated, use method 3):
+ * a = text1, b = text2, c = diffs
+ *
+ * @param {string|!Array.<!diff_match_patch.Diff>} a text1 (methods 1,3,4) or
+ * Array of diff tuples for text1 to text2 (method 2).
+ * @param {string|!Array.<!diff_match_patch.Diff>} opt_b text2 (methods 1,4) or
+ * Array of diff tuples for text1 to text2 (method 3) or undefined (method 2).
+ * @param {string|!Array.<!diff_match_patch.Diff>} opt_c Array of diff tuples
+ * for text1 to text2 (method 4) or undefined (methods 1,2,3).
+ * @return {!Array.<!diff_match_patch.patch_obj>} Array of patch objects.
+ */
+diff_match_patch.prototype.patch_make = function(a, opt_b, opt_c) {
+ var text1, diffs;
+ if (typeof a == 'string' && typeof opt_b == 'string' &&
+ typeof opt_c == 'undefined') {
+ // Method 1: text1, text2
+ // Compute diffs from text1 and text2.
+ text1 = /** @type {string} */(a);
+ diffs = this.diff_main(text1, /** @type {string} */(opt_b), true);
+ if (diffs.length > 2) {
+ this.diff_cleanupSemantic(diffs);
+ this.diff_cleanupEfficiency(diffs);
+ }
+ } else if (a && typeof a == 'object' && typeof opt_b == 'undefined' &&
+ typeof opt_c == 'undefined') {
+ // Method 2: diffs
+ // Compute text1 from diffs.
+ diffs = /** @type {!Array.<!diff_match_patch.Diff>} */(a);
+ text1 = this.diff_text1(diffs);
+ } else if (typeof a == 'string' && opt_b && typeof opt_b == 'object' &&
+ typeof opt_c == 'undefined') {
+ // Method 3: text1, diffs
+ text1 = /** @type {string} */(a);
+ diffs = /** @type {!Array.<!diff_match_patch.Diff>} */(opt_b);
+ } else if (typeof a == 'string' && typeof opt_b == 'string' &&
+ opt_c && typeof opt_c == 'object') {
+ // Method 4: text1, text2, diffs
+ // text2 is not used.
+ text1 = /** @type {string} */(a);
+ diffs = /** @type {!Array.<!diff_match_patch.Diff>} */(opt_c);
+ } else {
+ throw new Error('Unknown call format to patch_make.');
+ }
+
+ if (diffs.length === 0) {
+ return []; // Get rid of the null case.
+ }
+ var patches = [];
+ var patch = new diff_match_patch.patch_obj();
+ var patchDiffLength = 0; // Keeping our own length var is faster in JS.
+ var char_count1 = 0; // Number of characters into the text1 string.
+ var char_count2 = 0; // Number of characters into the text2 string.
+ // Start with text1 (prepatch_text) and apply the diffs until we arrive at
+ // text2 (postpatch_text). We recreate the patches one by one to determine
+ // context info.
+ var prepatch_text = text1;
+ var postpatch_text = text1;
+ for (var x = 0; x < diffs.length; x++) {
+ var diff_type = diffs[x][0];
+ var diff_text = diffs[x][1];
+
+ if (!patchDiffLength && diff_type !== DIFF_EQUAL) {
+ // A new patch starts here.
+ patch.start1 = char_count1;
+ patch.start2 = char_count2;
+ }
+
+ switch (diff_type) {
+ case DIFF_INSERT:
+ patch.diffs[patchDiffLength++] = diffs[x];
+ patch.length2 += diff_text.length;
+ postpatch_text = postpatch_text.substring(0, char_count2) + diff_text +
+ postpatch_text.substring(char_count2);
+ break;
+ case DIFF_DELETE:
+ patch.length1 += diff_text.length;
+ patch.diffs[patchDiffLength++] = diffs[x];
+ postpatch_text = postpatch_text.substring(0, char_count2) +
+ postpatch_text.substring(char_count2 +
+ diff_text.length);
+ break;
+ case DIFF_EQUAL:
+ if (diff_text.length <= 2 * this.Patch_Margin &&
+ patchDiffLength && diffs.length != x + 1) {
+ // Small equality inside a patch.
+ patch.diffs[patchDiffLength++] = diffs[x];
+ patch.length1 += diff_text.length;
+ patch.length2 += diff_text.length;
+ } else if (diff_text.length >= 2 * this.Patch_Margin) {
+ // Time for a new patch.
+ if (patchDiffLength) {
+ this.patch_addContext_(patch, prepatch_text);
+ patches.push(patch);
+ patch = new diff_match_patch.patch_obj();
+ patchDiffLength = 0;
+ // Unlike Unidiff, our patch lists have a rolling context.
+ // http://code.google.com/p/google-diff-match-patch/wiki/Unidiff
+ // Update prepatch text & pos to reflect the application of the
+ // just completed patch.
+ prepatch_text = postpatch_text;
+ char_count1 = char_count2;
+ }
+ }
+ break;
+ }
+
+ // Update the current character count.
+ if (diff_type !== DIFF_INSERT) {
+ char_count1 += diff_text.length;
+ }
+ if (diff_type !== DIFF_DELETE) {
+ char_count2 += diff_text.length;
+ }
+ }
+ // Pick up the leftover patch if not empty.
+ if (patchDiffLength) {
+ this.patch_addContext_(patch, prepatch_text);
+ patches.push(patch);
+ }
+
+ return patches;
+};
+
+
+/**
+ * Given an array of patches, return another array that is identical.
+ * @param {!Array.<!diff_match_patch.patch_obj>} patches Array of patch objects.
+ * @return {!Array.<!diff_match_patch.patch_obj>} Array of patch objects.
+ */
+diff_match_patch.prototype.patch_deepCopy = function(patches) {
+ // Making deep copies is hard in JavaScript.
+ var patchesCopy = [];
+ for (var x = 0; x < patches.length; x++) {
+ var patch = patches[x];
+ var patchCopy = new diff_match_patch.patch_obj();
+ patchCopy.diffs = [];
+ for (var y = 0; y < patch.diffs.length; y++) {
+ patchCopy.diffs[y] = patch.diffs[y].slice();
+ }
+ patchCopy.start1 = patch.start1;
+ patchCopy.start2 = patch.start2;
+ patchCopy.length1 = patch.length1;
+ patchCopy.length2 = patch.length2;
+ patchesCopy[x] = patchCopy;
+ }
+ return patchesCopy;
+};
+
+
+/**
+ * Merge a set of patches onto the text. Return a patched text, as well
+ * as a list of true/false values indicating which patches were applied.
+ * @param {!Array.<!diff_match_patch.patch_obj>} patches Array of patch objects.
+ * @param {string} text Old text.
+ * @return {!Array.<string|!Array.<boolean>>} Two element Array, containing the
+ * new text and an array of boolean values.
+ */
+diff_match_patch.prototype.patch_apply = function(patches, text) {
+ if (patches.length == 0) {
+ return [text, []];
+ }
+
+ // Deep copy the patches so that no changes are made to originals.
+ patches = this.patch_deepCopy(patches);
+
+ var nullPadding = this.patch_addPadding(patches);
+ text = nullPadding + text + nullPadding;
+
+ this.patch_splitMax(patches);
+ // delta keeps track of the offset between the expected and actual location
+ // of the previous patch. If there are patches expected at positions 10 and
+ // 20, but the first patch was found at 12, delta is 2 and the second patch
+ // has an effective expected position of 22.
+ var delta = 0;
+ var results = [];
+ for (var x = 0; x < patches.length; x++) {
+ var expected_loc = patches[x].start2 + delta;
+ var text1 = this.diff_text1(patches[x].diffs);
+ var start_loc;
+ var end_loc = -1;
+ if (text1.length > this.Match_MaxBits) {
+ // patch_splitMax will only provide an oversized pattern in the case of
+ // a monster delete.
+ start_loc = this.match_main(text, text1.substring(0, this.Match_MaxBits),
+ expected_loc);
+ if (start_loc != -1) {
+ end_loc = this.match_main(text,
+ text1.substring(text1.length - this.Match_MaxBits),
+ expected_loc + text1.length - this.Match_MaxBits);
+ if (end_loc == -1 || start_loc >= end_loc) {
+ // Can't find valid trailing context. Drop this patch.
+ start_loc = -1;
+ }
+ }
+ } else {
+ start_loc = this.match_main(text, text1, expected_loc);
+ }
+ if (start_loc == -1) {
+ // No match found. :(
+ results[x] = false;
+ // Subtract the delta for this failed patch from subsequent patches.
+ delta -= patches[x].length2 - patches[x].length1;
+ } else {
+ // Found a match. :)
+ results[x] = true;
+ delta = start_loc - expected_loc;
+ var text2;
+ if (end_loc == -1) {
+ text2 = text.substring(start_loc, start_loc + text1.length);
+ } else {
+ text2 = text.substring(start_loc, end_loc + this.Match_MaxBits);
+ }
+ if (text1 == text2) {
+ // Perfect match, just shove the replacement text in.
+ text = text.substring(0, start_loc) +
+ this.diff_text2(patches[x].diffs) +
+ text.substring(start_loc + text1.length);
+ } else {
+ // Imperfect match. Run a diff to get a framework of equivalent
+ // indices.
+ var diffs = this.diff_main(text1, text2, false);
+ if (text1.length > this.Match_MaxBits &&
+ this.diff_levenshtein(diffs) / text1.length >
+ this.Patch_DeleteThreshold) {
+ // The end points match, but the content is unacceptably bad.
+ results[x] = false;
+ } else {
+ this.diff_cleanupSemanticLossless(diffs);
+ var index1 = 0;
+ var index2;
+ for (var y = 0; y < patches[x].diffs.length; y++) {
+ var mod = patches[x].diffs[y];
+ if (mod[0] !== DIFF_EQUAL) {
+ index2 = this.diff_xIndex(diffs, index1);
+ }
+ if (mod[0] === DIFF_INSERT) { // Insertion
+ text = text.substring(0, start_loc + index2) + mod[1] +
+ text.substring(start_loc + index2);
+ } else if (mod[0] === DIFF_DELETE) { // Deletion
+ text = text.substring(0, start_loc + index2) +
+ text.substring(start_loc + this.diff_xIndex(diffs,
+ index1 + mod[1].length));
+ }
+ if (mod[0] !== DIFF_DELETE) {
+ index1 += mod[1].length;
+ }
+ }
+ }
+ }
+ }
+ }
+ // Strip the padding off.
+ text = text.substring(nullPadding.length, text.length - nullPadding.length);
+ return [text, results];
+};
+
+
+/**
+ * Add some padding on text start and end so that edges can match something.
+ * Intended to be called only from within patch_apply.
+ * @param {!Array.<!diff_match_patch.patch_obj>} patches Array of patch objects.
+ * @return {string} The padding string added to each side.
+ */
+diff_match_patch.prototype.patch_addPadding = function(patches) {
+ var paddingLength = this.Patch_Margin;
+ var nullPadding = '';
+ for (var x = 1; x <= paddingLength; x++) {
+ nullPadding += String.fromCharCode(x);
+ }
+
+ // Bump all the patches forward.
+ for (var x = 0; x < patches.length; x++) {
+ patches[x].start1 += paddingLength;
+ patches[x].start2 += paddingLength;
+ }
+
+ // Add some padding on start of first diff.
+ var patch = patches[0];
+ var diffs = patch.diffs;
+ if (diffs.length == 0 || diffs[0][0] != DIFF_EQUAL) {
+ // Add nullPadding equality.
+ diffs.unshift([DIFF_EQUAL, nullPadding]);
+ patch.start1 -= paddingLength; // Should be 0.
+ patch.start2 -= paddingLength; // Should be 0.
+ patch.length1 += paddingLength;
+ patch.length2 += paddingLength;
+ } else if (paddingLength > diffs[0][1].length) {
+ // Grow first equality.
+ var extraLength = paddingLength - diffs[0][1].length;
+ diffs[0][1] = nullPadding.substring(diffs[0][1].length) + diffs[0][1];
+ patch.start1 -= extraLength;
+ patch.start2 -= extraLength;
+ patch.length1 += extraLength;
+ patch.length2 += extraLength;
+ }
+
+ // Add some padding on end of last diff.
+ patch = patches[patches.length - 1];
+ diffs = patch.diffs;
+ if (diffs.length == 0 || diffs[diffs.length - 1][0] != DIFF_EQUAL) {
+ // Add nullPadding equality.
+ diffs.push([DIFF_EQUAL, nullPadding]);
+ patch.length1 += paddingLength;
+ patch.length2 += paddingLength;
+ } else if (paddingLength > diffs[diffs.length - 1][1].length) {
+ // Grow last equality.
+ var extraLength = paddingLength - diffs[diffs.length - 1][1].length;
+ diffs[diffs.length - 1][1] += nullPadding.substring(0, extraLength);
+ patch.length1 += extraLength;
+ patch.length2 += extraLength;
+ }
+
+ return nullPadding;
+};
+
+
+/**
+ * Look through the patches and break up any which are longer than the maximum
+ * limit of the match algorithm.
+ * Intended to be called only from within patch_apply.
+ * @param {!Array.<!diff_match_patch.patch_obj>} patches Array of patch objects.
+ */
+diff_match_patch.prototype.patch_splitMax = function(patches) {
+ var patch_size = this.Match_MaxBits;
+ for (var x = 0; x < patches.length; x++) {
+ if (patches[x].length1 > patch_size) {
+ var bigpatch = patches[x];
+ // Remove the big old patch.
+ patches.splice(x--, 1);
+ var start1 = bigpatch.start1;
+ var start2 = bigpatch.start2;
+ var precontext = '';
+ while (bigpatch.diffs.length !== 0) {
+ // Create one of several smaller patches.
+ var patch = new diff_match_patch.patch_obj();
+ var empty = true;
+ patch.start1 = start1 - precontext.length;
+ patch.start2 = start2 - precontext.length;
+ if (precontext !== '') {
+ patch.length1 = patch.length2 = precontext.length;
+ patch.diffs.push([DIFF_EQUAL, precontext]);
+ }
+ while (bigpatch.diffs.length !== 0 &&
+ patch.length1 < patch_size - this.Patch_Margin) {
+ var diff_type = bigpatch.diffs[0][0];
+ var diff_text = bigpatch.diffs[0][1];
+ if (diff_type === DIFF_INSERT) {
+ // Insertions are harmless.
+ patch.length2 += diff_text.length;
+ start2 += diff_text.length;
+ patch.diffs.push(bigpatch.diffs.shift());
+ empty = false;
+ } else if (diff_type === DIFF_DELETE && patch.diffs.length == 1 &&
+ patch.diffs[0][0] == DIFF_EQUAL &&
+ diff_text.length > 2 * patch_size) {
+ // This is a large deletion. Let it pass in one chunk.
+ patch.length1 += diff_text.length;
+ start1 += diff_text.length;
+ empty = false;
+ patch.diffs.push([diff_type, diff_text]);
+ bigpatch.diffs.shift();
+ } else {
+ // Deletion or equality. Only take as much as we can stomach.
+ diff_text = diff_text.substring(0,
+ patch_size - patch.length1 - this.Patch_Margin);
+ patch.length1 += diff_text.length;
+ start1 += diff_text.length;
+ if (diff_type === DIFF_EQUAL) {
+ patch.length2 += diff_text.length;
+ start2 += diff_text.length;
+ } else {
+ empty = false;
+ }
+ patch.diffs.push([diff_type, diff_text]);
+ if (diff_text == bigpatch.diffs[0][1]) {
+ bigpatch.diffs.shift();
+ } else {
+ bigpatch.diffs[0][1] =
+ bigpatch.diffs[0][1].substring(diff_text.length);
+ }
+ }
+ }
+ // Compute the head context for the next patch.
+ precontext = this.diff_text2(patch.diffs);
+ precontext =
+ precontext.substring(precontext.length - this.Patch_Margin);
+ // Append the end context for this patch.
+ var postcontext = this.diff_text1(bigpatch.diffs)
+ .substring(0, this.Patch_Margin);
+ if (postcontext !== '') {
+ patch.length1 += postcontext.length;
+ patch.length2 += postcontext.length;
+ if (patch.diffs.length !== 0 &&
+ patch.diffs[patch.diffs.length - 1][0] === DIFF_EQUAL) {
+ patch.diffs[patch.diffs.length - 1][1] += postcontext;
+ } else {
+ patch.diffs.push([DIFF_EQUAL, postcontext]);
+ }
+ }
+ if (!empty) {
+ patches.splice(++x, 0, patch);
+ }
+ }
+ }
+ }
+};
+
+
+/**
+ * Take a list of patches and return a textual representation.
+ * @param {!Array.<!diff_match_patch.patch_obj>} patches Array of patch objects.
+ * @return {string} Text representation of patches.
+ */
+diff_match_patch.prototype.patch_toText = function(patches) {
+ var text = [];
+ for (var x = 0; x < patches.length; x++) {
+ text[x] = patches[x];
+ }
+ return text.join('');
+};
+
+
+/**
+ * Parse a textual representation of patches and return a list of patch objects.
+ * @param {string} textline Text representation of patches.
+ * @return {!Array.<!diff_match_patch.patch_obj>} Array of patch objects.
+ * @throws {!Error} If invalid input.
+ */
+diff_match_patch.prototype.patch_fromText = function(textline) {
+ var patches = [];
+ if (!textline) {
+ return patches;
+ }
+ var text = textline.split('\n');
+ var textPointer = 0;
+ var patchHeader = /^@@ -(\d+),?(\d*) \+(\d+),?(\d*) @@$/;
+ while (textPointer < text.length) {
+ var m = text[textPointer].match(patchHeader);
+ if (!m) {
+ throw new Error('Invalid patch string: ' + text[textPointer]);
+ }
+ var patch = new diff_match_patch.patch_obj();
+ patches.push(patch);
+ patch.start1 = parseInt(m[1], 10);
+ if (m[2] === '') {
+ patch.start1--;
+ patch.length1 = 1;
+ } else if (m[2] == '0') {
+ patch.length1 = 0;
+ } else {
+ patch.start1--;
+ patch.length1 = parseInt(m[2], 10);
+ }
+
+ patch.start2 = parseInt(m[3], 10);
+ if (m[4] === '') {
+ patch.start2--;
+ patch.length2 = 1;
+ } else if (m[4] == '0') {
+ patch.length2 = 0;
+ } else {
+ patch.start2--;
+ patch.length2 = parseInt(m[4], 10);
+ }
+ textPointer++;
+
+ while (textPointer < text.length) {
+ var sign = text[textPointer].charAt(0);
+ try {
+ var line = decodeURI(text[textPointer].substring(1));
+ } catch (ex) {
+ // Malformed URI sequence.
+ throw new Error('Illegal escape in patch_fromText: ' + line);
+ }
+ if (sign == '-') {
+ // Deletion.
+ patch.diffs.push([DIFF_DELETE, line]);
+ } else if (sign == '+') {
+ // Insertion.
+ patch.diffs.push([DIFF_INSERT, line]);
+ } else if (sign == ' ') {
+ // Minor equality.
+ patch.diffs.push([DIFF_EQUAL, line]);
+ } else if (sign == '@') {
+ // Start of next patch.
+ break;
+ } else if (sign === '') {
+ // Blank line? Whatever.
+ } else {
+ // WTF?
+ throw new Error('Invalid patch mode "' + sign + '" in: ' + line);
+ }
+ textPointer++;
+ }
+ }
+ return patches;
+};
+
+
+/**
+ * Class representing one patch operation.
+ * @constructor
+ */
+diff_match_patch.patch_obj = function() {
+ /** @type {!Array.<!diff_match_patch.Diff>} */
+ this.diffs = [];
+ /** @type {?number} */
+ this.start1 = null;
+ /** @type {?number} */
+ this.start2 = null;
+ /** @type {number} */
+ this.length1 = 0;
+ /** @type {number} */
+ this.length2 = 0;
+};
+
+
+/**
+ * Emmulate GNU diff's format.
+ * Header: @@ -382,8 +481,9 @@
+ * Indicies are printed as 1-based, not 0-based.
+ * @return {string} The GNU diff string.
+ */
+diff_match_patch.patch_obj.prototype.toString = function() {
+ var coords1, coords2;
+ if (this.length1 === 0) {
+ coords1 = this.start1 + ',0';
+ } else if (this.length1 == 1) {
+ coords1 = this.start1 + 1;
+ } else {
+ coords1 = (this.start1 + 1) + ',' + this.length1;
+ }
+ if (this.length2 === 0) {
+ coords2 = this.start2 + ',0';
+ } else if (this.length2 == 1) {
+ coords2 = this.start2 + 1;
+ } else {
+ coords2 = (this.start2 + 1) + ',' + this.length2;
+ }
+ var text = ['@@ -' + coords1 + ' +' + coords2 + ' @@\n'];
+ var op;
+ // Escape the body of the patch with %xx notation.
+ for (var x = 0; x < this.diffs.length; x++) {
+ switch (this.diffs[x][0]) {
+ case DIFF_INSERT:
+ op = '+';
+ break;
+ case DIFF_DELETE:
+ op = '-';
+ break;
+ case DIFF_EQUAL:
+ op = ' ';
+ break;
+ }
+ text[x + 1] = op + encodeURI(this.diffs[x][1]) + '\n';
+ }
+ return text.join('').replace(/%20/g, ' ');
+};
+
+
+// Export these global variables so that they survive Google's JS compiler.
+// In a browser, 'this' will be 'window'.
+// In node.js 'this' will be a global object.
+this['diff_match_patch'] = diff_match_patch;
+this['DIFF_DELETE'] = DIFF_DELETE;
+this['DIFF_INSERT'] = DIFF_INSERT;
+this['DIFF_EQUAL'] = DIFF_EQUAL;
+
+}).apply(typeof exports != "undefined" ? exports : window);
381 src/jsondiffpatch.js
@@ -0,0 +1,381 @@
+
+(function(){
+
+ var jdp = {};
+
+ jdp.config = {
+ textDiffMinLength: 60,
+ };
+
+ jdp.dateReviver = function(key, value){
+ var a;
+ if (typeof value === 'string') {
+ a = /^(\d{4})-(\d{2})-(\d{2})T(\d{2}):(\d{2}):(\d{2}(?:\.\d*)?)(Z|([+\-])(\d{2}):(\d{2}))$/.exec(value);
+ if (a) {
+ return new Date(Date.UTC(+a[1], +a[2] - 1, +a[3], +a[4], +a[5], +a[6]));
+ }
+ }
+ return value;
+ }
+
+ var diff_match_patch_autoconfig = function(){
+ if (diff_match_patch) {
+ var dmp;
+ if (typeof diff_match_patch == 'function') {
+ dmp = new diff_match_patch();
+ }
+ else
+ if (typeof diff_match_patch == 'object' &&
+ typeof diff_match_patch.diff_match_patch == 'function') {
+ dmp = new diff_match_patch.diff_match_patch();
+ }
+ if (dmp) {
+ jdp.config.textDiff = function(txt1, txt2){
+ return dmp.patch_toText(dmp.patch_make(txt1, txt2));
+ }
+ jdp.config.textPatch = function(txt1, patch){
+ var results = dmp.patch_apply(dmp.patch_fromText(patch), txt1);
+ for (var i = 0; i < results[1].length; i++) {
+ if (!results[1][i]) {
+ throw new Error('text patch failed');
+ }
+ }
+ return results[0];
+ };
+ return true;
+ }
+ }
+ }
+
+ var arrayDiff = function(o, n){
+ var adiff, i, idiff, nl = n.length, ol = o.length, addItemDiff;
+
+ addItemDiff = function(index){
+ idiff = diff(o[index], n[index]);
+ if (typeof idiff != 'undefined') {
+ if (typeof adiff == 'undefined') {
+ adiff = {
+ _t: 'a'
+ };
+ }
+ adiff[index] = idiff;
+ }
+ };
+
+ for (i = 0; i < Math.max(nl, ol); i++) {
+ addItemDiff(i);
+ }
+ return adiff;
+ };
+
+ var arrayDiffByKey = function(o, n, itemKey){
+ var adiff, ol = o.length, nl = n.length, getKey, dcount = 0;
+
+ if (typeof itemKey == 'function') {
+ getKey = itemKey;
+ }
+ else {
+ getKey = function(item){
+ return item[itemKey];
+ }
+ }
+
+ for (var i = 0; i < nl; i++) {
+ if (typeof adiff == 'undefined') {
+ adiff = {
+ _t: 'a'
+ };
+ }
+ // added, changed or unchanged
+ adiff[getKey(n[i])] = [n[i]];
+ dcount++;
+ }
+ for (var i = 0; i < ol; i++) {
+ var key = getKey(o[i]);
+ if (typeof adiff == 'undefined' || typeof adiff[key] == 'undefined') {
+ if (typeof adiff == 'undefined') {
+ adiff = {
+ _t: 'a'
+ };
+ }
+ // deleted
+ adiff[key] = [o[i], 0, 0];
+ dcount++;
+ }
+ else {
+ var d = diff(o[i], adiff[key][0]);
+ if (typeof d == 'undefined') {
+ // unchanged
+ delete adiff[key];
+ dcount--;
+ }
+ else {
+ // changed
+ adiff[key] = d;
+ }
+ }
+ }
+ if (dcount > 0) {
+ return adiff;
+ }
+ else {
+ // no changes
+ return;
+ }
+ };
+
+ var objectDiff = function(o, n){
+