linters/xo: consolidate xo linters

autoload/ale/handlers/xo.vim

@@ -0,0 +1,28 @@
+call ale#Set('javascript_xo_executable', 'xo')
+call ale#Set('javascript_xo_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('javascript_xo_options', '')
+
+call ale#Set('typescript_xo_executable', 'xo')
+call ale#Set('typescript_xo_use_global', get(g:, 'ale_use_global_executables', 0))
+call ale#Set('typescript_xo_options', '')
+
+function! ale#handlers#xo#GetExecutable(buffer, type) abort
+    return ale#node#FindExecutable(a:buffer, a:type . '_xo', [
+    \   'node_modules/.bin/xo',
+    \])
+endfunction
+
+function! ale#handlers#xo#GetLintCommand(buffer, type) abort
+    return ale#Escape(ale#handlers#xo#GetExecutable(a:buffer, a:type))
+    \   . ale#Pad(ale#handlers#xo#GetOptions(a:buffer, a:type))
+    \   . ' --reporter json --stdin --stdin-filename %s'
+endfunction
+
+function! ale#handlers#xo#GetOptions(buffer, type) abort
+    return ale#Var(a:buffer, a:type . '_xo_options')
+endfunction
+
+" xo uses eslint and the output format is the same
+function! ale#handlers#xo#HandleJSON(buffer, lines) abort
+    return ale#handlers#eslint#HandleJSON(a:buffer, a:lines)
+endfunction