--benchmark, fixes #217

[gurgeous]

This is not done yet, but I thought you might want to take a look. Maybe something like this? See sample output below. A few questions:

• should I add tests? not sure if that's useful here, let me know
• I could try to load/use TableTennis if available, without adding a dependency.. any interest?
• want me to modify the changelog? anything else?

Thanks!!

$ image_optim --benchmark -r /tmp/corpus/

benchmarking: 100.0% (elapsed: 3.9m)

BENCHMARK RESULTS

name      files  elapsed  kb saved     kb/s
--------  -----  -------  --------  -------
oxipng       50    8.906  1867.253  209.664
pngquant     50    1.980   214.597  108.386
pngcrush     50   22.529  1753.704   77.841
optipng      50  142.940  1641.101   11.481
advpng       50  137.753   962.549    6.987
pngout       50  426.706   444.679    1.042

[gurgeous]

One rubocop issue remaining:

lib/image_optim.rb:28:1: C: Metrics/ClassLength: Class has too many lines. [170/150]
class ImageOptim ...
^^^^^^^^^^^^^^^^

There are many ways to fix this, but I always try to avoid refactors in other people's projects :) Happy to address this if you give me some direction.

[toy]

Sorry for the wait. Works well, most important comments are for lib/image_optim.rb, everything else is code style and nitpicks.

About tests - better to know if it will break, so at least on the level of that it works.

About TableTennis - I understand the desire to make it beautiful, but the output is so simple, that it feels excessive. From one side it shouldn't add more than few lines of code, from the other there are lots of different gems to print a table in terminal and everyone may have their preferred one.

About changelog entry - definitely and some mention in readme

[toy]

I'm not sure if applying worker always to the original is more informative then doing it in chain (on result of previous worker) as will be done during normal operation

[gurgeous]

Maybe we can add a --chain later if people like this. I think those results would be interesting as well, especially now that I've seen the worker_analysis script

[gurgeous]

Thanks for the feedback! I added a simple test and applied the feedback. I think this is ready for another look now, no rush