erblint as fixer (#3935)

* fixer erblint

* erblint fixer test

autoload/ale/fix/registry.vim

@@ -100,6 +100,11 @@ let s:default_registry = {
 \       'suggested_filetypes': ['nim'],
 \       'description': 'Apply nimpretty to a file.',
 \   },
+\   'erblint': {
+\       'function': 'ale#fixers#erblint#Fix',
+\       'suggested_filetypes': ['eruby'],
+\       'description': 'Apply erblint --autocorrect to a file.',
+\   },
 \   'eslint': {
 \       'function': 'ale#fixers#eslint#Fix',
 \       'suggested_filetypes': ['javascript', 'typescript'],

autoload/ale/fixers/erblint.vim

@@ -0,0 +1,40 @@
+" Author: Roeland Moors - https://github.com/roelandmoors
+" Description: ERB Lint, support for https://github.com/Shopify/erb-lint
+
+call ale#Set('eruby_erblint_executable', 'erblint')
+call ale#Set('eruby_erblint_options', '')
+
+
+" Erblint fixer outputs diagnostics first and then the fixed
+" output. These are delimited by something like this:
+" ================ /path/to/demo.html.erb ==================
+" We only need the output after this
+function! ale#fixers#erblint#PostProcess(buffer, output) abort
+    let l:line = 0
+
+    for l:output in a:output
+        let l:line = l:line + 1
+
+        if l:output =~# "^=\\+.*=\\+$"
+            break
+        endif
+    endfor
+
+    return a:output[l:line :]
+endfunction
+
+function! ale#fixers#erblint#GetCommand(buffer) abort
+    let l:executable = ale#Var(a:buffer, 'eruby_erblint_executable')
+    let l:options = ale#Var(a:buffer, 'eruby_erblint_options')
+
+    return ale#ruby#EscapeExecutable(l:executable, 'erblint')
+    \   . (!empty(l:options) ? ' ' . l:options : '')
+    \   . ' --autocorrect --stdin %s'
+endfunction
+
+function! ale#fixers#erblint#Fix(buffer) abort
+    return {
+    \   'command': ale#fixers#erblint#GetCommand(a:buffer),
+    \   'process_with': 'ale#fixers#erblint#PostProcess'
+    \}
+endfunction