Consider php lint for Github Actions

[indigoxela]

Description of the need

It doesn't happen often, but sometimes a syntax error sneaks in.
It can be a more obvious one that only got overlooked in a very big PR, for instance in an automated test. It can be a more subtle one, that only strikes on older PHP versions (short array syntax, using empty() with non-variables...) (the oldest officially supported PHP version is now 5.6.)

Anyway, it would be so easy to prevent that by simply running php -l on all changed files, for the oldest and newest PHP Backdrop supports.

Additional information

Not sure if this works as-is in the runners, but here's a simple bash one-liner that works for me locally:

git diff --name-only 1.x... | while read LINE; do php -l $LINE; done;

Feedback is welcome. 😃

[klonos]

We should also consider https://github.com/overtrue/phplint

Related: overtrue/phplint#33

[indigoxela]

We should also consider https://github.com/overtrue/phplint

Hm. An action that requires extra installs (composer / docker) to accomplish the same as with a Bash one-liner? Are you sure?

[klonos]

Are you sure?

I'm not sure. That's why I said "we should consider".

[quicksketch]

I think it sounds like a low-cost addition. I would think that 9 out of 10 situations any syntax errors would be caught by SimpleTest, but as we found in the 1.20.0 release, we accidentally let in a syntax error in one of the test files themselves, which didn't cause a failure but just silently skipped that test and passed the build (a separate problem). I could also see updating uncommonly included files such as .install files being left out of SimpleTest runs potentially causing issues. When we decide to bump the PHP minimum version from 5.3 to anything higher, we may see bulk updates converting array() to [] syntax, which would be a likely scenario to introduce parsing errors that might not get individual testing.

So, seems like a good idea. 👍

There would be the very small cost that it will use one of our concurrent GitHub Action threads, but I wouldn't expect it to run for more than 10-20 seconds, depending on how fast the GitHub Action container itself starts up.

[indigoxela]

A PR at an early stage exists.

Note that it doesn't make sense to use a full runner just for php -l. My actual proposal is to merge with #5245 and possibly #5467 (if people want that one, too) into a single workflow, so we don't waste our available runners.

This is the outcome:

Feedback is welcome - as always 😉

[indigoxela]

In case someone wonders, where the log format for GHA (annotations) are documented: here

[indigoxela]

Now with a red title containing file and line (more like the phpcs action does it):

The the job name is a bit too long ... "Check for syntax errors". It looks fine in the workflow yml file, but in the annotation... 🤔