[WIP] Fish completion #725

[volkov]

Fish completion POC (#725). Very dirty and buggy at the moment, but works nice for my scenario.

Definitely, it's early for reviewing of this changes, but early adopters of this thing are welcome.

[remkop]

Awesome, @volkov thank you for working on this! 👍
Will you be able to provide some unit tests?

[volkov]

Yes, I have begun to move towards testing, however, my progress is currently moderate as I am not familiar with dejagnu
I think I'll be back in couple of weeks.

[remkop]

Hi @volkov looks like you have made great progress! I took a brief look and I see you are also adding dejaGnu tests, much appreciated! I remember it took me a long time to wrap my head around the dejaGnu test framework, not trivial! 😅

Were you able to make dejaGnu start a fish shell session instead of a bash session? I took a quick look at src/test/dejagnu.tests/lib/library.exp (I suspect that some work may be needed there) but I haven't figured it out yet. Looking at the start_bash function, it may be as simple as setting --tool_exec to fish, but perhaps that is not even needed, not sure...

If your dejaGnu tests work, can we call them from JUnit, maybe from src/test/java/picocli/AutoCompleteDejaGnuTest.java?

Again, thanks a lot for your contributions here! Much appreciated! 🙏

[remkop]

I found some usages of Java 8 API, but picocli is compiled with Java 5, so we cannot use that (String.join). Can you take a look?

[volkov]

Were you able to make dejaGnu start a fish shell session instead of a bash session?

Yes, At the moment I use separate file dejagnu.fishtests/lib/completion.exp with exp_spawn fish --no-config

If your dejaGnu tests work, can we call them from JUnit, maybe from src/test/java/picocli/AutoCompleteDejaGnuTest.java?

Fish tests work on my notebook, at the moment there is only subset of bash tests. Bash tests for some reason don't work on my notebook, but I didn't investigate it yet.

Yes, It's good idea to integrate them with junit.

Also I think its important to make them work in github actions.

I'll try to return to this pr in couple of weeks.

[volkov]

Currently tests on github are flaky, don't know why (locally they are quite stable).

I want to investigate what's wrong, but I don't know when.