Integrate phan tests with Travis CI

[phan]

Integrate phan tests with Travis CI

[jazzdan]

Note that this is going to be slightly tricky because of the dependency on the php-ast extension which isn't in pecl yet. I think we'll have to build the extension manually in the travis environment.

This restriction also means that we will not be able to run tests agains the nightly builds of PHP which is a bit of a bummer.

[cweagans]

1. Do we really need to run it against PHP nightlies? I think 7.0.0 is probably adequate for now.
2. You could run it in a Docker container with the ast extension pre-installed. Happy to build this image if needed. I'm doing something similar for https://github.com/cweagans/mcrypt-polyfill, so happy to set it up for this project too if needed.

[jazzdan]

Hey @cweagans,

We definitely don't need to run it against the nightlies, but this feels like the type of code that might break with new versions of PHP so running it against nightlies will be valuable I think.

Also I know very little about Travis CI, this would be my first time setting it up! Can you provide them an arbitrary Docker container to run the tests in? If so then I think that's a great solution.

[cweagans]

@jazzdan Well, it's not really "officially" supported, I guess. I'm just running arbitrary containers in https://github.com/cweagans/mcrypt-polyfill/blob/master/tests/run-tests.sh (and the specific contents of the container vary by environment).

phpseclib takes a different approach (https://github.com/phpseclib/phpseclib/blob/master/.travis.yml#L30) which also works well.

[scaytrase]

Returning to this thread - travis is already integrated and add (or not) nightly would be easy implementation, so I suggest to decide and close this.

[cweagans]

I think we can close this now.