RazorFormat.MinifyHtml breaks javascript

cdmackie · April 8, 2015, 11:06pm

I am using the RazorFormat minify, e.g.

Plugins.Add(new RazorFormat() { MinifyHtml = true });

But it is changing embedded script code within a page:

<script>
  var $$$$name = 1;
</script>

becomes

<script>
  var $name = 1;
</script>

I am using angular and so referencing their existing variable “$$childHead”. Re-factoring will move the code out later, but for now it breaks.
.

mythz · April 9, 2015, 6:25am

The minifiers is using a C# port of Google’s HtmlCompressor and Crockfords JSMin where there is some JS Code it doesn’t like, the only workaround is to change the variable names to make the minifiers happy.

Rob · April 9, 2015, 4:49pm

I may be able to fix this. CDMackie, can you post a full file with the failing script?

@Mythz: the JSMin port of flawed is a number of ways, I will try to fix that.

cdmackie · April 9, 2015, 6:22pm

Hi Rob

Here is a working project showing the issue.

Cheers

Colin

cdmackie · April 13, 2015, 6:28pm

The original Java code uses Matcher.quoteReplacement, which deliberately stops / and $ from having any special meaning:

https://code.google.com/p/htmlcompressor/source/browse/trunk/src/main/java/com/googlecode/htmlcompressor/compressor/HtmlCompressor.java (line 469)

The C# version is using match.Result which is doing token replacement, such that “$$” becomes “$”. This would cause similar problems if any variables were named, or started with, “$1”.

C# doesn’t have an equivalent of quoteReplacement, so you could probably resort to using Replace, as you only need to escape / and $ (rather than using Regex.Escape).

So, in ServiceStack/Html/Minifiers.html.cs (forum won’t let me link more than 2 things!)

line 1026

sb.Append(match.Result(/*Regex.Escape*/(scriptBlocks[i])));

Should become

sb.Append(match.Result(scriptBlocks[i].Replace("\\", "\\\\").Replace("$$", "$$$$")));

mythz · April 14, 2015, 4:01am

Nice Catch! I’ve made the proposed change which is now available on MyGet: https://github.com/ServiceStack/ServiceStack/wiki/MyGet

Please let me know if this resolves the issue.

cdmackie · September 7, 2016, 6:05pm

Have to re-open this old thread because I’ve just been caught out by the fix I had suggested.

I was getting a problem with “” escaped within inline scripts, and it’s my own fix! Oops, sorry.

The original issue with $ is still valid, but it’s the backslash that’s the issue. It doesn’t actually get replaced in Regex.Replace like $ does, so is just causing “” to become “\\”.

github.com

ServiceStack/ServiceStack/blob/master/src/ServiceStack/Html/Minifiers.html.cs#L1027


    var sb = StringBuilderCache.Allocate();
    var lastValue = 0;


    foreach (Match match in matcher)
    {
        int i = int.Parse(match.Groups[1].Value);
        if (scriptBlocks.Count > i)
        {
            sb.Append(html.Substring(lastValue, match.Index - lastValue));
            //matcher.appendReplacement(sb, Regex.Escape(scriptBlocks[i]));
            sb.Append(match.Result(scriptBlocks[i].Replace("$", "$$")));


            lastValue = match.Index + match.Length;
        }
    }


    //matcher.appendTail(sb);
    sb.Append(html.Substring(lastValue));


    html = StringBuilderCache.ReturnAndFree(sb);
}

sb.Append(match.Result(scriptBlocks[i].Replace("\\", "\\\\").Replace("$$", "$$$$")));

needs to just be

sb.Append(match.Result(scriptBlocks[i].Replace("$$", "$$$$")));

See my updated project showing the issue: jsminbug-20160907

mythz · September 7, 2016, 7:18pm

ok thanks, fix is now in this commit, which is now available on MyGet.