Only show secondary icon for know filenames and extensions

[Hirse]

The best way to explain is probably by example:

Here I have three files with a secondary icon.
The first one - correctly - because of the combination of filename and file extension is somewhat reserved.
The second one - also correctly - because it has a secondary file extension.
The third one - in my opinion incorrectly - because the svg is not a secondary file extension but just the name of the file.

[cgfrost]

To put it another way, you think the first element (the bit before the first dot) of a file name should be ignored unless it's a known file name such as package.json?

[Hirse]

Yes, pretty much.
To be more precise, in a filename with many dots only the part after the second last dot should be considered.

[cgfrost]

That change would mean a little more. e.g. foo.js.bar.boo would currently get the extension for a JS file. If we ignore everything before the second from last dot it will only get the default icon. @ivogabe What do you think? (I'm happy to do the work for this change, I have some spare time tomorrow, I don't want to barge in before you though)

[ivogabe]

I think the behavior proposed by @Hirse is the best. svg.html is probably not a svg file, only a html file and foo.js.bar.boo is probably not a javascript file, so we should give it the default icon. A file like foo.js.bar is comparable to foo.js.php, it can be for instance a .bar / .php file that generates a .js file, so we should give foo.js.bar the default icon as primary icon and .js as secondary.

[cgfrost]

@ivogabe OK, do you mind if I make this change and fix the bug in the other issue at the same time. Will be much quicker because I already started playing with this before the bug was raised?

[ivogabe]

@cgfrost That would be great

[cgfrost]

This pull request will fix things. (I'll stop tweeking the pull request as well)

[yvza]

How about this? http://prnt.sc/eta6rj
@cgfrost