feat: support Bazel `buildifier` linter (#4529)

* Initial buildifier linter files

* Add handler test

* Fix test when options are not set

1 files changed, 40 insertions, 0 deletions

diff --git a/ale_linters/bzl/buildifier.vim b/ale_linters/bzl/buildifier.vim
new file mode 100644
index 00000000..42cd3cd9
--- /dev/null
+++ b/ale_linters/bzl/buildifier.vim
@@ -0,0 +1,40 @@
+" Author: Chuck Grindel <chuck.grindel@gmail.com>
+" Description: Bazel Starlark lint support using buildifier.
+
+function! ale_linters#bzl#buildifier#GetCommand(buffer) abort
+    let l:executable = ale#Escape(ale#fixers#buildifier#GetExecutable(a:buffer))
+    let l:options = ale#Var(a:buffer, 'bazel_buildifier_options')
+    let l:filename = ale#Escape(bufname(a:buffer))
+
+    let l:command = l:executable . ' -mode check -lint warn -path %s'
+
+    if l:options isnot# ''
+        let l:command .= ' ' . l:options
+    endif
+
+    return l:command
+endfunction
+
+function! ale_linters#bzl#buildifier#Handle(buffer, lines) abort
+    let l:pattern = '\v^[^:]+:(\d+):(\d+)?:?\s+(syntax error near)?(.+)$'
+    let l:output = []
+
+    for l:match in ale#util#GetMatches(a:lines, l:pattern)
+        call add(l:output, {
+        \   'lnum': l:match[1] + 0,
+        \   'col': l:match[2] + 0,
+        \   'text': l:match[3] . l:match[4],
+        \   'type': l:match[3] is# 'syntax error near' ? 'E' : 'W',
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('bzl', {
+\   'name': 'buildifier',
+\   'output_stream': 'both',
+\   'executable': function('ale#fixers#buildifier#GetExecutable'),
+\   'command': function('ale_linters#bzl#buildifier#GetCommand'),
+\   'callback': function('ale_linters#bzl#buildifier#Handle'),
+\})