Fix #308 - Check Dart files with dartanalyzer

ale_linters/dart/dartanalyzer.vim

@@ -0,0 +1,40 @@
+" Author: w0rp <devw0rp@gmail.com>
+" Description: Check Dart files with dartanalyzer
+
+call ale#Set('dart_dartanalyzer_executable', 'dartanalyzer')
+
+function! ale_linters#dart#dartanalyzer#GetExecutable(buffer) abort
+    return ale#Var(a:buffer, 'dart_dartanalyzer_executable')
+endfunction
+
+function! ale_linters#dart#dartanalyzer#GetCommand(buffer) abort
+    let l:executable = ale_linters#dart#dartanalyzer#GetExecutable(a:buffer)
+    let l:path = ale#path#FindNearestFile(a:buffer, '.packages')
+
+    return ale#Escape(l:executable)
+    \   . (!empty(l:path) ? ' --packages ' . ale#Escape(l:path) : '')
+    \   . ' %t'
+endfunction
+
+function! ale_linters#dart#dartanalyzer#Handle(buffer, lines) abort
+    let l:pattern = '\v^  ([a-z]+) . (.+) at (.+):(\d+):(\d+) . (.+)$'
+    let l:output = []
+
+    for l:match in ale#util#GetMatches(a:lines, l:pattern)
+        call add(l:output, {
+        \   'type': l:match[1] ==# 'error' ? 'E' : 'W',
+        \   'text': l:match[6] . ': ' . l:match[2],
+        \   'lnum': str2nr(l:match[4]),
+        \   'col': str2nr(l:match[5]),
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('dart', {
+\   'name': 'dartanalyzer',
+\   'executable_callback': 'ale_linters#dart#dartanalyzer#GetExecutable',
+\   'command_callback': 'ale_linters#dart#dartanalyzer#GetCommand',
+\   'callback': 'ale_linters#dart#dartanalyzer#Handle',
+\})