2 * Javascript Diff Algorithm
3 * By John Resig (http://ejohn.org/)
4 * Modified by Chu Alan "sprite"
6 * Released under the MIT license.
9 * http://ejohn.org/projects/javascript-diff-algorithm/
14 n = n.replace(/&/g, "&");
15 n = n.replace(/</g, "<");
16 n = n.replace(/>/g, ">");
17 n = n.replace(/"/g, """);
22 function diffString( o, n ) {
23 o = o.replace(/\s+$/, '');
24 n = n.replace(/\s+$/, '');
26 var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );
29 var oSpace = o.match(/\s+/g);
35 var nSpace = n.match(/\s+/g);
42 if (out.n.length == 0) {
43 for (var i = 0; i < out.o.length; i++) {
44 str += '<del>' + escape(out.o[i]) + oSpace[i] + "</del>";
47 if (out.n[0].text == null) {
48 for (n = 0; n < out.o.length && out.o[n].text == null; n++) {
49 str += '<del>' + escape(out.o[n]) + oSpace[n] + "</del>";
53 for ( var i = 0; i < out.n.length; i++ ) {
54 if (out.n[i].text == null) {
55 str += '<ins>' + escape(out.n[i]) + nSpace[i] + "</ins>";
59 for (n = out.n[i].row + 1; n < out.o.length && out.o[n].text == null; n++ ) {
60 pre += '<del>' + escape(out.o[n]) + oSpace[n] + "</del>";
62 str += " " + out.n[i].text + nSpace[i] + pre;
70 function randomColor() {
71 return "rgb(" + (Math.random() * 100) + "%, " +
72 (Math.random() * 100) + "%, " +
73 (Math.random() * 100) + "%)";
75 function diffString2( o, n ) {
76 o = o.replace(/\s+$/, '');
77 n = n.replace(/\s+$/, '');
79 var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );
81 var oSpace = o.match(/\s+/g);
87 var nSpace = n.match(/\s+/g);
95 var colors = new Array();
96 for (var i = 0; i < out.o.length; i++) {
97 colors[i] = randomColor();
99 if (out.o[i].text != null) {
100 os += '<span style="background-color: ' +colors[i]+ '">' +
101 escape(out.o[i].text) + oSpace[i] + "</span>";
103 os += "<del>" + escape(out.o[i]) + oSpace[i] + "</del>";
108 for (var i = 0; i < out.n.length; i++) {
109 if (out.n[i].text != null) {
110 ns += '<span style="background-color: ' +colors[out.n[i].row]+ '">' +
111 escape(out.n[i].text) + nSpace[i] + "</span>";
113 ns += "<ins>" + escape(out.n[i]) + nSpace[i] + "</ins>";
117 return { o : os , n : ns };
120 function diff( o, n ) {
121 var ns = new Object();
122 var os = new Object();
124 for ( var i = 0; i < n.length; i++ ) {
125 if ( ns[ n[i] ] == null )
126 ns[ n[i] ] = { rows: new Array(), o: null };
127 ns[ n[i] ].rows.push( i );
130 for ( var i = 0; i < o.length; i++ ) {
131 if ( os[ o[i] ] == null )
132 os[ o[i] ] = { rows: new Array(), n: null };
133 os[ o[i] ].rows.push( i );
136 for ( var i in ns ) {
137 if ( ns[i].rows.length == 1 && typeof(os[i]) != "undefined" && os[i].rows.length == 1 ) {
138 n[ ns[i].rows[0] ] = { text: n[ ns[i].rows[0] ], row: os[i].rows[0] };
139 o[ os[i].rows[0] ] = { text: o[ os[i].rows[0] ], row: ns[i].rows[0] };
143 for ( var i = 0; i < n.length - 1; i++ ) {
144 if ( n[i].text != null && n[i+1].text == null && n[i].row + 1 < o.length && o[ n[i].row + 1 ].text == null &&
145 n[i+1] == o[ n[i].row + 1 ] ) {
146 n[i+1] = { text: n[i+1], row: n[i].row + 1 };
147 o[n[i].row+1] = { text: o[n[i].row+1], row: i + 1 };
151 for ( var i = n.length - 1; i > 0; i-- ) {
152 if ( n[i].text != null && n[i-1].text == null && n[i].row > 0 && o[ n[i].row - 1 ].text == null &&
153 n[i-1] == o[ n[i].row - 1 ] ) {
154 n[i-1] = { text: n[i-1], row: n[i].row - 1 };
155 o[n[i].row-1] = { text: o[n[i].row-1], row: i - 1 };
159 return { o: o, n: n };