The Travis environment is terribly outdated, and they are not really
subtly pushing people to use Docker to set up their own containerised CI
environments instead of pulling from Ubuntu 12.04 or 14.04.
Let's try using this approach:
- create a Docker image that pulls from Debian Stretch
- set up a build and test environment
- push the image to the Docker Hub
- create a derived Docker image that copies the Epoxy repo
when running under Travis
- run the build and test script inside the derived image
This is similar to what Meson does for its CI.
We don't really use `sudo` anywhere, except for installing packages;
this means we should be able to use the faster container-based
environment on Travis, instead of the VM-based one.
This isn't quite as good as I'd like -- the XVFB setup doesn't support
a bunch of context creation extensions that we use, and I haven't
looked into the multiplatform stuff for doing OS X testing yet. I
think it's a good start, though.
Emmanuele Bassi
Eric Anholt