Travis broken for < 9.4

[nasbyj]

Travis no longer passes for master. https://travis-ci.org/theory/pgtap/builds/496774630 shows as clean, but that’s from 7 months ago. https://travis-ci.org/nasbyj/pgtap/builds/591752270 is a straight branch right off of master and it’s broken.

The bottom of https://travis-ci.org/nasbyj/pgtap/jobs/592145045 shows the contents of the extensions directory, which is definitely missing all extensions other than pgTap and plpgsql.

I see two options:

1. Simply stop testing extension test functions in < 9.4. Note that 8.4 and 9.0 are broken for other reasons, so this wouldn't fix those versions.
2. Formally drop support for < 9.4.

Given that 9.4 will be EOL this year, I'm inclined to go with option 2.

[theory]

Do we need to install another package that includes contrib extensions?

[decibel]

Looks like github didn't like my email reply...

Maybe https://packages.debian.org/jessie/postgresql-contrib-9.4 is the explanation for this? Though if that was really the case then why isn't 9.4 broken?

BTW, I'm getting ready to merge #128, which moves the Travis test script into our repository. So if we need to pull in additional packages or something we can do that.

Do you have a linux environment similar to Travis available @theory? (I don't). Can you take a look at the contrib issue?

[decibel]

Oh, I just realized that #128 has code to disable the extensions test if any extensions are not available. (I should really add a WARNING when that happens...) Maybe we can go with that? I'm still not keen on having stuff that's officially supported but doesn't have automated testing though...

[theory]

No, I don't. I guess if I was doing this again, I'd try to use the community Apt repos instead. Or find some way to spin up docker images and use those, instead.

[theory]

Okay, looks like Travis updated their build images, and the Postgres Apt repo doesn't have older versions of Postgres for some versions of Ubuntu. For Xenial, for example, there is no version prior to 9.1. The way to address this, I think, it to instead use a Docker image for each version. I might play around with that a bit next week in some of my other, simpler extensions, and maybe we can adapt it here.

[nasbyj]

It looks like going the Docker route would also make it easy to run the travis tests locally, which would be a huge win.

[theory]

Yeah, but the official Postgres image only goes back to 9.4, too. :-(

[cbandy]

There are old tags, too. https://hub.docker.com/_/postgres?tab=tags&page=12

[theory]

Travis stuff replaced with GitHub workflows in 2ccda7f.