Yuglify fails to parse jquery.js

[jdufresne]

Steps to reproduce:

$ rm -rf bower_components && bower cache clean && bower install jquery#~1.11
bower deleted       Cached package jquery: /home/jon/.cache/bower/packages/fe2fe255e91d251051d543998aa8327a/1.11.0
bower jquery#~1.11          not-cached git://github.com/jquery/jquery.git#~1.11
bower jquery#~1.11             resolve git://github.com/jquery/jquery.git#~1.11
bower jquery#~1.11            download https://github.com/jquery/jquery/archive/1.11.0.tar.gz
bower jquery#~1.11             extract archive.tar.gz
bower jquery#~1.11            resolved git://github.com/jquery/jquery.git#1.11.0
bower jquery#~1.11             install jquery#1.11.0

jquery#1.11.0 bower_components/jquery

$ yuglify bower_components/jquery/dist/jquery.js 
Compressing bower_components/jquery/dist/jquery.js...

/home/jon/node_modules/yuglify/bin/yuglify:111
                    throw(err);
                          ^
Error
    at new JS_Parse_Error (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:263:18)
    at js_error (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:271:11)
    at croak (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:733:9)
    at token_error (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:740:9)
    at unexpected (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:746:9)
    at /home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1112:13
    at maybe_unary (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1209:19)
    at expr_ops (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1236:24)
    at maybe_conditional (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1240:20)
    at maybe_assign (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1264:20)
    at /home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1278:20
    at vardefs (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1065:32)
    at var_ (/home/jon/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1077:26)

This failure to parse occurred some time between jQuery 1.10 and 1.11 as 1.10 parses fine:

$ rm -rf bower_components && bower cache clean && bower install jquery#~1.10
bower deleted       Cached package jquery: /home/jon/.cache/bower/packages/fe2fe255e91d251051d543998aa8327a/1.10.2
bower jquery#~1.10          not-cached git://github.com/jquery/jquery.git#~1.10
bower jquery#~1.10             resolve git://github.com/jquery/jquery.git#~1.10
bower jquery#~1.10            download https://github.com/jquery/jquery/archive/1.10.2.tar.gz
bower jquery#~1.10             extract archive.tar.gz
bower jquery#~1.10            resolved git://github.com/jquery/jquery.git#1.10.2
bower jquery#~1.10             install jquery#1.10.2

jquery#1.10.2 bower_components/jquery

$ yuglify bower_components/jquery/jquery.js 
Compressing bower_components/jquery/jquery.js...
Successfully generated JS file: bower_components/jquery/jquery.min.js

I submitted a bug to jQuery, but they believe this is a Yuglify bug. See: http://bugs.jquery.com/ticket/14998

[pmclanahan]

Seeing same issue with jQuery 2.1.0.

[dorey]

I'm finding it has to do with an exclamation mark at the beginning of a comment in the middle of a variable assignment. (Happens in jQuery when Sizzle is defined)

/*! this comment is okay */
X = /* and this is okay */ Y;
X = /*! <-- but the "!" here causes an error */ Y;

[dorey]

It is fixed by @leik 's fix suggested in this pull request which fixes the case when an IIFE follows the comment.

On testing it again, it looks like it's not fixed by that pull request.

[wreiske]

Still having an issue with this with Jquery-1.11.1.js

Compressing ./js/jquery-1.11.1.js...

/usr/local/lib/node_modules/yuglify/bin/yuglify:111
                    throw(err);
                          ^
Error
    at new JS_Parse_Error (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:263:18)
    at js_error (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:271:11)
    at croak (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:733:9)
    at token_error (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:740:9)
    at unexpected (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:746:9)
    at /usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1112:13
    at maybe_unary (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1209:19)
    at expr_ops (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1236:24)
    at maybe_conditional (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1240:20)
    at maybe_assign (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1264:20)
    at /usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1278:20
    at vardefs (/usr/local/lib/node_modules/yuglify/node_modules/uglify-js/lib/parse-js.js:1065:32)

You can easily get this to work by removing the comment blocks including the /*! comments.

Beginning of the file, and where it shows "sizzle". Once they are removed yuglify works as normal.

[ewjoachim]

I'm willing to downgrade my jquery and/or yuglify versions if that can make it work (its far easier for me than modifying the code of jquery, because we don't really include the code for thirdparties in our projects. Do anyone know what versions of jquery/yuglify should I use, while waiting for the fix ? Thank you !

[Matt-Deacalion]

@ewjoachim works ok with jquery version 2.0.3.

[jensenbox]

I can confirm that removing the two comment blocks starting with /*! resolves the compile issue.

[mrcoles]

Considering that jQuery 2.x doesn't support IE8, lots of people will still be using jQuery 1.11+ for the near future, which still has this problem. I'm going to just use "uglify-js" in the meantime.

[Luis-Palacios]

any updates on this one? with v2.1.3 the issue still remains, btw i can also confirm that by removing the two comment blocks starting with /*! resolves the compile issue.

[sassanh]

any workaround except changing jquery's code?

[apendua]

Same story, here. BTW, I am wondering why yuglify fails to show a comprehensive error message.

[apendua]

Lemme explain why this is happening. When you look at the jquery source code at the beginning of Sizzle section, line 548 in my case, you will see this:

var Sizzle =
/*!
 * Sizzle CSS Selector Engine v2.2.0-pre
 * http://sizzlejs.com/
 *
 * Copyright 2008, 2014 jQuery Foundation, Inc. and other contributors
 * Released under the MIT license
 * http://jquery.org/license
 *
 * Date: 2014-12-16
 */
(function( window ) {
  // ...
});

which looks totally fine at first sight. However, during the compilation process yuglify decides to replace the block comment with the following code:

var Sizzle =
;"yUglify: preserved comment block";
(function( window ) {
  // ...
});

This fails to be a valid JavaScript.

So the question here is why do we want to replace a block comment with something which has a semantic meaning. I think everyone understand the reason something has to be done, because otherwise the minify process might break things. However, we could replace that block comment with something more like:

/* */

which should not break anything and it's shorter then the current solution.

[apendua]

Ah! I can see what you did there

https://github.com/yui/yuglify/blob/master/lib/jsminify.js#L44-L50

I understand that this is a hack there to prevent uglify-js from removing those comments. Hmm ... I think that this issue shows that the hack is not good enough.

[apendua]

Turns out, not having an ability to preserve "license" comments is a long existing issue in uglify-js.