check-completions.fish fails when completion command exists but errors

[VulpineAmethyst]

check-completions.fish fails when completion command exists but errors

[faho]

What that test does is source the completion if a command by the given name exists:

fish-shell/tests/checks/check-completions.fish

Lines 6 to 10 in b64c210

	if type -q (string replace -r '.*/([^/]+).fish' '$1' $f)
	set -l out (source $f 2>&1 | string collect)
	test -n "$out"
	and echo -- OUTPUT from $f: $out
	end

If that then prints anything, the test fails. It doesn't specifically care about what the command-to-be-completed is, or if it returns anything in specific, just the load-time behavior of the completion script (e.g. broken complete calls).

What error specifically are you seeing?

[VulpineAmethyst]

What we were encountering specifically was an issue caused by pip3 (for some reason) expecting /usr/bin/python to exist when our Python package only provides /usr/bin/python3.

[faho]

The pip3 completion script in 3.7.1 calls pip3:

fish-shell/share/completions/pip3.fish

Line 5 in 80394ea

pip3 completion --fish 2>/dev/null | string replace -r -- " -c\s+pip\b" " -c pip3" | source

If that wants to run /usr/bin/python, then that is a real bug that manifests on your system (whether it is in pip3 or in Adélie's packaging), and any user who has pip3 installed but not /usr/bin/python would see error output and a non-functioning completion.

This appears to be working as intended.

[faho]

Note: pip3's output here is pretty cheesy:

# pip fish completion start
function __fish_complete_pip
    set -lx COMP_WORDS (commandline -o) ""
    set -lx COMP_CWORD ( \
        math (contains -i -- (commandline -t) $COMP_WORDS)-1 \
    )
    set -lx PIP_AUTO_COMPLETE 1
    string split \  -- (eval $COMP_WORDS[1])
end
complete -fa "(__fish_complete_pip)" -c pip3
# pip fish completion end

This does not call /usr/bin/python anywhere, so I suspect the issue to be in a shebang somewhere. This would have to be fixed.

[VulpineAmethyst]

Yeah. The underlying issue is definitely on Python's end (and could be in our Python recipe), but fish could very well be installed on a system that doesn't have Python installed (e.g. my development VM only installs Python when building packages that depend on it, and it is otherwise not present, and I use fish there).

[faho]

First of all: Our test tool is written in python. So you can't actually run the tests on a system without.

And this only checks the completions for things you have installed - it will only check the pip completions if you have pip. And it told you that the pip completions are not working correctly on that system. This seems to be a good thing to test, the test is working as designed.

The test script is correct and good, the failure is either in the completion script or the system.

In this case I'm calling this failure a bug on Adélie's or pip's end - you appear to have installed a pip3 that is not working correctly. I don't think we can really make the pip3 completion script more defensive - all it does is (after checking that pip3 exists), ask pip3 for completions.

[VulpineAmethyst]

Fair enough.