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fuzzyfox/jsdiff.js

Forked from mbijon/jsdiff.js
Created October 15, 2013 16:13
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Revisions

  1. @mbijon mbijon created this gist Oct 9, 2012.
    160 changes: 160 additions & 0 deletions jsdiff.js
    View file
    Original file line number Diff line number Diff line change
    @@ -0,0 +1,160 @@
    /*
    * Javascript Diff Algorithm
    * By John Resig (http://ejohn.org/)
    * Modified by Chu Alan "sprite"
    *
    * Released under the MIT license.
    *
    * More Info:
    * http://ejohn.org/projects/javascript-diff-algorithm/
    */

    function escape(s) {
    var n = s;
    n = n.replace(/&/g, "&");
    n = n.replace(/</g, "&lt;");
    n = n.replace(/>/g, "&gt;");
    n = n.replace(/"/g, "&quot;");

    return n;
    }

    function diffString( o, n ) {
    o = o.replace(/\s+$/, '');
    n = n.replace(/\s+$/, '');

    var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );
    var str = "";

    var oSpace = o.match(/\s+/g);
    if (oSpace == null) {
    oSpace = ["\n"];
    } else {
    oSpace.push("\n");
    }
    var nSpace = n.match(/\s+/g);
    if (nSpace == null) {
    nSpace = ["\n"];
    } else {
    nSpace.push("\n");
    }

    if (out.n.length == 0) {
    for (var i = 0; i < out.o.length; i++) {
    str += '<del>' + escape(out.o[i]) + oSpace[i] + "</del>";
    }
    } else {
    if (out.n[0].text == null) {
    for (n = 0; n < out.o.length && out.o[n].text == null; n++) {
    str += '<del>' + escape(out.o[n]) + oSpace[n] + "</del>";
    }
    }

    for ( var i = 0; i < out.n.length; i++ ) {
    if (out.n[i].text == null) {
    str += '<ins>' + escape(out.n[i]) + nSpace[i] + "</ins>";
    } else {
    var pre = "";

    for (n = out.n[i].row + 1; n < out.o.length && out.o[n].text == null; n++ ) {
    pre += '<del>' + escape(out.o[n]) + oSpace[n] + "</del>";
    }
    str += " " + out.n[i].text + nSpace[i] + pre;
    }
    }
    }

    return str;
    }

    function randomColor() {
    return "rgb(" + (Math.random() * 100) + "%, " +
    (Math.random() * 100) + "%, " +
    (Math.random() * 100) + "%)";
    }
    function diffString2( o, n ) {
    o = o.replace(/\s+$/, '');
    n = n.replace(/\s+$/, '');

    var out = diff(o == "" ? [] : o.split(/\s+/), n == "" ? [] : n.split(/\s+/) );

    var oSpace = o.match(/\s+/g);
    if (oSpace == null) {
    oSpace = ["\n"];
    } else {
    oSpace.push("\n");
    }
    var nSpace = n.match(/\s+/g);
    if (nSpace == null) {
    nSpace = ["\n"];
    } else {
    nSpace.push("\n");
    }

    var os = "";
    var colors = new Array();
    for (var i = 0; i < out.o.length; i++) {
    colors[i] = randomColor();

    if (out.o[i].text != null) {
    os += '<span style="background-color: ' +colors[i]+ '">' +
    escape(out.o[i].text) + oSpace[i] + "</span>";
    } else {
    os += "<del>" + escape(out.o[i]) + oSpace[i] + "</del>";
    }
    }

    var ns = "";
    for (var i = 0; i < out.n.length; i++) {
    if (out.n[i].text != null) {
    ns += '<span style="background-color: ' +colors[out.n[i].row]+ '">' +
    escape(out.n[i].text) + nSpace[i] + "</span>";
    } else {
    ns += "<ins>" + escape(out.n[i]) + nSpace[i] + "</ins>";
    }
    }

    return { o : os , n : ns };
    }

    function diff( o, n ) {
    var ns = new Object();
    var os = new Object();

    for ( var i = 0; i < n.length; i++ ) {
    if ( ns[ n[i] ] == null )
    ns[ n[i] ] = { rows: new Array(), o: null };
    ns[ n[i] ].rows.push( i );
    }

    for ( var i = 0; i < o.length; i++ ) {
    if ( os[ o[i] ] == null )
    os[ o[i] ] = { rows: new Array(), n: null };
    os[ o[i] ].rows.push( i );
    }

    for ( var i in ns ) {
    if ( ns[i].rows.length == 1 && typeof(os[i]) != "undefined" && os[i].rows.length == 1 ) {
    n[ ns[i].rows[0] ] = { text: n[ ns[i].rows[0] ], row: os[i].rows[0] };
    o[ os[i].rows[0] ] = { text: o[ os[i].rows[0] ], row: ns[i].rows[0] };
    }
    }

    for ( var i = 0; i < n.length - 1; i++ ) {
    if ( n[i].text != null && n[i+1].text == null && n[i].row + 1 < o.length && o[ n[i].row + 1 ].text == null &&
    n[i+1] == o[ n[i].row + 1 ] ) {
    n[i+1] = { text: n[i+1], row: n[i].row + 1 };
    o[n[i].row+1] = { text: o[n[i].row+1], row: i + 1 };
    }
    }

    for ( var i = n.length - 1; i > 0; i-- ) {
    if ( n[i].text != null && n[i-1].text == null && n[i].row > 0 && o[ n[i].row - 1 ].text == null &&
    n[i-1] == o[ n[i].row - 1 ] ) {
    n[i-1] = { text: n[i-1], row: n[i].row - 1 };
    o[n[i].row-1] = { text: o[n[i].row-1], row: i - 1 };
    }
    }

    return { o: o, n: n };
    }