Debugging a cross browser bug in my company's product I came across this. I'm not certain what aspect of the JS sort method is involved. The situation is we have and array of objects, each of which has a "name" property that's a string. We want to sort the array, so I called sorted_ar = ar.sort(function(a,b){ return a.name > b.name; }); This worked fine in Firefox on Windows and Snow Leopard, in Chrome on Windows and Snow Leopard, but failed in IE7 (meh) and Safari on both platforms. I tried the WebKit nightly build (Version 4.0.4 (6531.21.10, r57054)) and it failed there too. Here's a complete test case: ----- var ar = new Array(); if (console == undefined) { var console = { log : function(s) { print(s) } } } ar[0] = {name: "zzz"}; ar[1] = {name: "qqq"}; ar[2] = {name: "mmm"}; ar[3] = {name: "aaa"}; function dump(a) { for(i=0; i< a.length; i++) { console.log(i + ": "+a[i].name); } } dump(ar); console.log("sorting"); sorted_ar = ar.sort(function(a,b){ console.log("services.sort: comparing "+a.name+" to "+b.name); return a.name > b.name; }); dump(ar); ----- (I added the console definition so it would run in a command line JS shell). The successful results look like this (FF/Mac): ---- 0: zzz 1: qqq 2: mmm 3: aaa sorting services.sort: comparing zzz to qqq services.sort: comparing zzz to mmm services.sort: comparing qqq to mmm services.sort: comparing zzz to aaa services.sort: comparing qqq to aaa services.sort: comparing mmm to aaa 0: aaa 1: mmm 2: qqq 3: zzz ---- and the failing ones like thi (Safari/Mac)s: ---- 0: zzz 1: qqq 2: mmm 3: aaa sorting services.sort: comparing qqq to zzz services.sort: comparing mmm to zzz services.sort: comparing mmm to qqq services.sort: comparing aaa to qqq services.sort: comparing aaa to mmm 0: zzz 1: qqq 2: mmm 3: aaa ---- This should be easy to reproduce by opening a WebInspector window and pasting the test code into the console.
Created attachment 52586 [details] Test case as an html file The problem with your test case is that your code is wrong. the comparator function you provide returns inconsistent values which per spec results in undefined sorting. Your comparator function is returning either true or false when it should be returning -1, 0, or 1, this means your comparator is inconsistent as if i pass the strings "a" and "b" in one order your comparison function returns true (eg. 1) -- meaning "greater" -- or the other order it returns false (eg. 0) -- meaning "same". You can read the documentation at https://developer.mozilla.org/en/Core_JavaScript_1.5_Reference/Objects/Array/sort