ci: Add GitHub Actions workflow

[jtojnar]

Depends on #20.

This will run tests on all supported PHP version 5.6 through 8.0 and check the coding style.

I have decided to use Nix to install different PHP versions since it is a tool I am most familiar with and allows using the same environment locally as on CI. (Think Docker but much more flexible.)

Nix provides nix-shell command which will enter a shell with all the dependencies installed into environment. And if you use it with direnv, you will be put into the environment automatically whenever you cd into the project directory in a terminal emulator.

You can also switch the used PHP version by changing matrix.phpPackage value in the flake.nix file and re-running nix-shell (or touch shell.nix if you use direnv).

For more information, check out fossar/selfoss@e0a0ee2/docs/content/docs/development/using-nix.md

[smottt]

I like this, will check once we get the rest sorted out. I have a local set up of some docker containers for multiple PHP versions which also include Xdebug etc and I can configure PHPStorm accordingly. Is it possible to have interpreter & debugger configured correctly with this?

[jtojnar]

You can enable the xdebug extension as follows:

--- a/flake.nix
+++ b/flake.nix
@@ -26,7 +26,9 @@
         pkgs = nixpkgs.legacyPackages.${system};
 
         # Create a PHP package from the selected PHP package.
-        php = phps.packages.${system}.${matrix.phpPackage};
+        php = phps.packages.${system}.${matrix.phpPackage}.withExtensions ({ enabled, all }: with all; enabled ++ [
+          xdebug
+        ]);
       in {
         # Expose shell environment for development.
         devShell.${system} = pkgs.mkShell {

PHP in the shell then has the extension loaded:

$ php -m | grep xdebug
xdebug

Not sure what else needs to be done to set it up for PHPStorm.

[jtojnar]

@smottt I cherry-picked changes from #19 and #20 and now the tests pass everywhere:

https://github.com/jtojnar/WideImage/actions/runs/475491846

Had to do some extra changes since PHPUnit 9 does not like assertInternalType (removed) or @expectedException annotation (not sure why).

[smottt]

@expectedException has been deprecated years ago, I guess it was also removed at some point.

I think I'll modify the formula for BMP size based on your comment (so it's easier to add support for other than 24-bit if we want that at some point in the future) and merge #19, then #20 and let's see what's left here afterwards.

[jtojnar]

Not sure if adding more bit depths is worth it GD supports BMP since PHP 7.2 and BMP is quite obscure format these days.

[smottt]

I forgot about that. Seems that TGA is also supported from 7.4 on, so could introduce native support for those two without custom mappers then at some point. Thanks for the tip!

[smottt]

Is this correct?

[jtojnar]

The way Nix works, it takes build instructions for packages and builds them. It can also substitute the build result from a cache to reduce work. But since these are custom packages, they are not built by the official build servers and we need to use our own cache. I added a comment with a link to the repository that builds it.

[smottt]

Usually lock files are not committed for libraries. Not sure if this should be here or not, though?

[jtojnar]

This is lockfile for the CI, not the library. I find it more reliable to have CI state locked and it will also allow you to use the exact same version of dependencies locally in nix-shell.