gzip - Is there a benefit to minifying JavaScript before gzipping it?

Question

Is there some valid purpose to minifying before compressing? It seems highly unlikely that the gzipped file is smaller if it's minified first.

I ask because diagnosing production problems in minified code is substantially more difficult, and I'm wondering if people are subjecting themselves to that for no purpose.

Answer 1

As for raw file size, here is a sample (jQuery 1.4.2):

$ curl http://code.jquery.com/jquery-1.4.2.js | gzip > jquery.gz
$ curl http://code.jquery.com/jquery-1.4.2.min.js | gzip > jquery-min.gz

$ ls -la jquery*
-rw-r--r--  1 me  staff  24545 Apr  7 12:02 jquery-min.gz
-rw-r--r--  1 me  staff  45978 Apr  7 12:02 jquery.gz

So the minified version is about half the size.