2 * Javascript Diff Algorithm
3 * By John Resig (http://ejohn.org/)
4 * Modified by Chu Alan "sprite"
7 * http://ejohn.org/projects/javascript-diff-algorithm/
12 n
= n
.replace(/&/g
, "&");
13 n
= n
.replace(/</g
, "<");
14 n
= n
.replace(/>/g
, ">");
15 n
= n
.replace(/"/g, ""
;");
20 function diffString( o, n ) {
21 o = o.replace(/\s+$/, '');
22 n = n.replace(/\s+$/, '');
24 var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );
27 var oSpace = o.match(/\s+/g);
33 var nSpace = n.match(/\s+/g);
40 if (out.n.length == 0) {
41 for (var i = 0; i < out.o.length; i++) {
42 str += '<del>' + escape(out.o[i]) + oSpace[i] + "</del
>";
45 if (out.n[0].text == null) {
46 for (n = 0; n < out.o.length && out.o[n].text == null; n++) {
47 str += '<del>' + escape(out.o[n]) + oSpace[n] + "</del
>";
51 for ( var i = 0; i < out.n.length; i++ ) {
52 if (out.n[i].text == null) {
53 str += '<ins>' + escape(out.n[i]) + nSpace[i] + "</ins
>";
57 for (n = out.n[i].row + 1; n < out.o.length && out.o[n].text == null; n++ ) {
58 pre += '<del>' + escape(out.o[n]) + oSpace[n] + "</del
>";
60 str += " " + out.n[i].text + nSpace[i] + pre;
68 function randomColor() {
69 return "rgb(" + (Math.random() * 100) + "%, " +
70 (Math.random() * 100) + "%, " +
71 (Math.random() * 100) + "%)";
73 function diffString2( o, n ) {
74 o = o.replace(/\s+$/, '');
75 n = n.replace(/\s+$/, '');
77 var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );
79 var oSpace = o.match(/\s+/g);
85 var nSpace = n.match(/\s+/g);
93 var colors = new Array();
94 for (var i = 0; i < out.o.length; i++) {
95 colors[i] = randomColor();
97 if (out.o[i].text != null) {
98 os += '<span style="background
-color
: ' +colors[i]+ '">' +
99 escape(out.o[i].text) + oSpace[i] + "</span
>";
101 os += "<del
>" + escape(out.o[i]) + oSpace[i] + "</del
>";
106 for (var i = 0; i < out.n.length; i++) {
107 if (out.n[i].text != null) {
108 ns += '<span style="background
-color
: ' +colors[out.n[i].row]+ '">' +
109 escape(out.n[i].text) + nSpace[i] + "</span
>";
111 ns += "<ins
>" + escape(out.n[i]) + nSpace[i] + "</ins
>";
115 return { o : os , n : ns };
118 function diff( o, n ) {
119 var ns = new Object();
120 var os = new Object();
122 for ( var i = 0; i < n.length; i++ ) {
123 if ( ns[ n[i] ] == null )
124 ns[ n[i] ] = { rows: new Array(), o: null };
125 ns[ n[i] ].rows.push( i );
128 for ( var i = 0; i < o.length; i++ ) {
129 if ( os[ o[i] ] == null )
130 os[ o[i] ] = { rows: new Array(), n: null };
131 os[ o[i] ].rows.push( i );
134 for ( var i in ns ) {
135 if ( ns[i].rows.length == 1 && typeof(os[i]) != "undefined" && os[i].rows.length == 1 ) {
136 n[ ns[i].rows[0] ] = { text: n[ ns[i].rows[0] ], row: os[i].rows[0] };
137 o[ os[i].rows[0] ] = { text: o[ os[i].rows[0] ], row: ns[i].rows[0] };
141 for ( var i = 0; i < n.length - 1; i++ ) {
142 if ( n[i].text != null && n[i+1].text == null && n[i].row + 1 < o.length && o[ n[i].row + 1 ].text == null &&
143 n[i+1] == o[ n[i].row + 1 ] ) {
144 n[i+1] = { text: n[i+1], row: n[i].row + 1 };
145 o[n[i].row+1] = { text: o[n[i].row+1], row: i + 1 };
149 for ( var i = n.length - 1; i > 0; i-- ) {
150 if ( n[i].text != null && n[i-1].text == null && n[i].row > 0 && o[ n[i].row - 1 ].text == null &&
151 n[i-1] == o[ n[i].row - 1 ] ) {
152 n[i-1] = { text: n[i-1], row: n[i].row - 1 };
153 o[n[i].row-1] = { text: o[n[i].row-1], row: i - 1 };
157 return { o: o, n: n };