Started adding julia languageserver

ale_linters/julia/languageserver.vim

@@ -0,0 +1,30 @@
+" Author: Bartolomeo Stellato <bartolomeo.stellato@gmail.com>
+" Description: A language server for Julia
+
+call ale#Set('julia_languageserver_executable', 'julia')
+call ale#Set('julia_languageserver_use_global', get(g:, 'ale_use_global_executables', 0))
+
+function! ale_linters#julia#languageserver#GetExecutable(buffer) abort
+        let l:binary = ale#Var(a:buffer, 'julia_languageserver_executable')
+        return ale#Escape(l:binary)
+endfunction
+
+function! ale_linters#julia#languageserver#GetCommand(buffer) abort
+    let l:executable = ale_linters#julia#languageserver#GetExecutable(a:buffer)
+    let l:options = '--startup-file=no --history-file=no -e ' . '"
+\       using LanguageServer;
+\       server = LanguageServer.LanguageServerInstance(STDIN, STDOUT, false);
+\       server.runlinter = true;
+\       run(server);"'
+
+    return ale#Escape(l:executable) . ale#Escape(l:options)
+
+endfunction
+
+call ale#linter#Define('julia', {
+\   'name': 'languageserver',
+\   'lsp': 'stdio',
+\   'executable_callback': 'ale_linters#julia#languageserver#GetExecutable',
+\   'command_callback': 'ale_linters#julia#languageserver#GetCommand',
+\   'project_root_callback': 'ale#julia#FindProjectRoot',
+\})

autoload/ale/julia.vim

@@ -0,0 +1,21 @@
+" Set just so tests can override it.
+let g:__ale_julia_project_filenames = ['.git/HEAD']
+function! ale#julia#FindProjectRoot(buffer) abort
+    for l:project_filename in g:__ale_julia_project_filenames
+        let l:full_path = ale#path#FindNearestFile(a:buffer, l:project_filename)
+
+        if !empty(l:full_path)
+            let l:path = fnamemodify(l:full_path, ':h')
+
+            " Correct .git path detection.
+            if fnamemodify(l:path, ':t') is# '.git'
+                let l:path = fnamemodify(l:path, ':h')
+            endif
+
+            return l:path
+        endif
+    endfor
+
+    return ''
+endfunction
+