Add solhint support

ale_linters/solidity/solhint.vim

@@ -0,0 +1,29 @@
+" Author: Franco Victorio - https://github.com/fvictorio
+" Description: Report errors in Solidity code with solhint
+
+function! ale_linters#solidity#solhint#Handle(buffer, lines) abort
+    " Matches patterns like the following:
+    " /path/to/file/file.sol: line 1, col 10, Error - 'addOne' is defined but never used. (no-unused-vars)
+
+    let l:pattern = '\v^[^:]+: line (\d+), col (\d+), (Error|Warning) - (.*)$'
+    let l:output = []
+
+    for l:match in ale#util#GetMatches(a:lines, l:pattern)
+        let l:isError = l:match[3] is? 'error'
+        call add(l:output, {
+        \   'lnum': l:match[1] + 0,
+        \   'col': l:match[2] + 0,
+        \   'text': l:match[4],
+        \   'type': l:isError ? 'E' : 'W'
+        \})
+    endfor
+
+    return l:output
+endfunction
+
+call ale#linter#Define('solidity', {
+\   'name': 'solhint',
+\   'executable': 'solhint',
+\   'command': 'solhint --formatter compact %t',
+\   'callback': 'ale_linters#solidity#solhint#Handle',
+\})