Added support for linting of proto files

[jeffwillette]

• added docs

I can add tests if they are necessary. I am not too familiar with vimscript so if tests are necessary some advice would be useful. Thanks

[w0rp]

It looks like *.proto is for checking files in the current directory. That will be expanded in the shell. Does this program read the file from stdin at all?

[jeffwillette]

hmm there seems to be no options for reading from stdin. Is there any bash hackery that can be done to pipe stdin to it? I played around with some things but I couldn't get it to work

[w0rp]

If the linter needs to look at files on disk, use 'lint_file': 1, so it only checks files on disk. Instead of something like *.proto, give it %s, so it checks just the file you're working on.

[jeffwillette]

ok, I am now getting an error because the protoc needs the parent directory of the .proto file. Is there a format directive to get that? I tried doing %s/../ but it didn't like that :(

EDIT: I managed to get it working with the %s directive call by embedding a dirname arg into the command

EDIT2: I see from reading other PR's that this needs to be usable without bash specific commands so I'll work on writing a command_callback

[w0rp]

You've got the right idea about using 'command_callback' here. What you should do is write a callback with 'command_callback' and add ale#Escape(expand('#' . a:buffer . ':p:h')) into the command to add the escaped directory name. That will work everywhere. Then add a test for the command callback in the test/command_callback directory. There are a few similar tests.

[jeffwillette]

I have what I think is a working function here (just from looking at others and copying) but I get an error when I open vim that says

Error detected while processing function ale#Queue[9]..ale#CallWithCooldown[9]..<SNR>17_ALEQueueImpl[41]..ale#Lint[12]..ale#CallWithCooldown[9]..<SNR>17
_ALELintImpl[16]..ale#engine#RunLinters[12]..<SNR>102_RunLinter[7]..<SNR>102_InvokeChain[1]..ale#engine#ProcessChain[52]..ale#linter#GetCommand:
line    1:
E117: Unknown function: ale_linters#proto#protocgenlint#GetCommand
E15: Invalid expression: has_key(a:linter, 'command_callback')   ? ale#util#GetFunction(a:linter.command_callback)(a:buffer)   : a:linter.command

this is the file as it is when it gives the error. I have tried numerous things and nothing has gotten it to work

function! ale_linters#proto#protocgenlint#GetCommand(buffer) abort
    let l:dirname = expand('#' . a:buffer . ':p:h')
    let l:filename = expand('#' . a:buffer)

    "\   'command': 'protoc -I $(dirname %s) --lint_out=. %s',

    return 'protoc'
    \   . '-I' . ale#Escape(l:dirname)
    \   . '--lint_out=.' . ale#Escape(l:filename)
endfunction

call ale#linter#Define('proto', {
\   'name': 'protoc-gen-lint',
\   'output_stream': 'stderr',
\   'lint_file': 1,
\   'executable': 'protoc',
\   'command_callback': 'ale_linters#proto#protocgenlint#GetCommand',
\   'callback': 'ale#handlers#unix#HandleAsError',
\})

EDIT:

It was a file naming issue. It appears the file name needed to match the function name. vim script is weird

[w0rp]

You can use just %s on the end there. ALE will automatically replace that with the filename.

[w0rp]

You can remove this comment now.

[w0rp]

Remove this entry and the documentation entry. There's no such linter with the name protoc.

[jeffwillette]

@w0rp after the test failed I tried every which way I could think of to add %s on the end and nothing worked

. ' --lint_out=. ' . '%s'
. ' --lint_out=. ' . expand('%s')
. ' --lint_out=. '%s'
. ' --lint_out=. ' ale#Escape('%s')
. ' --lint_out=. ' . ale#Escape(expand('#' . '%s')

all failed for me

[w0rp]

Put %s in the test too. %s is replaced later on by the engine.

[w0rp]

Okay, looks good. I'll add it to the README and the list in doc/ale.txt.