Update composer.json

[Arzaroth]

A straightforward change.
The goal of this PR is to have a php version requirement (I chose the lowest one from the CI setup) and also to install phpunit locally as a dev dependency.

[mikehaertl]

I agree to the PHP constraint but I'm not sure about phpunit. I'd rather leave this up to every developer. Some might prefer to install phpunit system wide. Actually I'm a bit confused about the require-dev section anyway. I think I remember that composer always installed everything. I may be wrong on this, though.

[mikehaertl]

How about a single >=5.4.0 here?

[Arzaroth]

That's what I did initially, CI failed for php7. You can see why in the output of job 99.

[mikehaertl]

Hmm, i see a ^5.4.0, not a >=5.4.0 in your initial commit.

[mikehaertl]

Regarding require-dev, now I remember. You explicitely have to tell composer that you don't want development dependencies installed with --no-dev. I don't like that default behaviour as it means, that you get a bloated vendor directory by default. So I'd say, let's leave that phpunit dependency out.

[Arzaroth]

From my point of view, it doesn't hurt to install phpunit locally even if it's already installed system wide.
I do agree about require-dev being confusing.
You have to run composer install with --no-dev switch to disable require-dev dependencies to be installed.
Although I'm not sure but I think require-dev dependencies are not installed when requiring a package that has them.

EDIT because of cross-post : Well yes, the vendor directory will be bloated for the local development version of this package, but not for those requiring this one.

[mikehaertl]

So far the development team is very small. I can't see why we want to bloat everyone elses vendor directory with phpunit. It's not required to use this library. And the few developers here will know how to install phpunit if they need it.

So: Sorry, I'm a bit insistent on this one. :). I have a personal aversion against software that doesn't respect my valuable disk space by default.

[Arzaroth]

Duly noted, I'll leave that out of this PR :).

[mikehaertl]

Great :). Can you also give >= 5.4.0 a try? The failed test had ^5.4.0. I personally prefer this notation as it's slightly easier to read (I always have to look up the exact meaning of ^).