lint: add g:go_metalinter_path setting

autoload/go/lint.vim

@@ -6,6 +6,10 @@ if !exists("g:go_metalinter_enabled")
     let g:go_metalinter_enabled = ['vet', 'golint', 'errcheck']
 endif
 
+if !exists("g:go_metalinter_path")
+    let g:go_metalinter_path = "./..."
+endif
+
 if !exists("g:go_golint_bin")
     let g:go_golint_bin = "golint"
 endif
@@ -14,36 +18,42 @@ if !exists("g:go_errcheck_bin")
     let g:go_errcheck_bin = "errcheck"
 endif
 
-function! go#lint#Gometa(...) abort
-    " change GOPATH too, so the underlying tools in gometalinter can pick up
-    " the correct GOPATH
-    let old_gopath = $GOPATH
-    let $GOPATH = go#path#Detect()
-
+function! go#lint#Gometa(path_to_lint) abort
     let meta_command = "gometalinter --disable-all"
     if empty(g:go_metalinter_command)
         let bin_path = go#path#CheckBinPath("gometalinter") 
         if empty(bin_path) 
             return 
         endif
 
+        if empty(g:go_metalinter_enabled)
+            echohl Error | echomsg "vim-go: please enable linters with the setting g:go_metalinter_enabled" | echohl None
+            return 
+        endif
+
         for linter in g:go_metalinter_enabled
             let meta_command .= " --enable=".linter
         endfor
 
-        " TODO(arslan): maybe this should be passed via argument?
-        " for now we search for all underlying files
-        let meta_command .=  " ./..."
+
+        " by default we search for all underlying files
+        let path = g:go_metalinter_path
+        if !empty(a:path_to_lint)
+            let path = a:path_to_lint
+        endif
+
+        let meta_command .=  path
     else
         " the user wants something else, let us use it.
         let meta_command = g:go_metalinter_command
     endif
 
-    " debug
+    " comment out the following two lines for debugging
     " echo meta_command
     " return
 
-    let out = system(meta_command)
+    let out = go#tool#ExecuteInDir(meta_command)
+
     if v:shell_error == 0
         redraw | echo
         call setqflist([])
@@ -63,9 +73,6 @@ function! go#lint#Gometa(...) abort
 
         let &errorformat = old_errorformat
     endif
-
-    " restore GOPATH again
-    let $GOPATH = old_gopath
 endfunction
 
 " Golint calls 'golint' on the current directory. Any warnings are populated in

doc/vim-go.txt

@@ -417,13 +417,15 @@ COMMANDS                                                          *go-commands*
     scope.
 
                                                               *:GoMetaLinter*
-:GoMetaLinter
+:GoMetaLinter [path]
 
     Calls the underlying `gometalinter` tool and displays all warnings and
-    errors in a quickfix window. By default the following linters are
-    enabled: "'vet', 'golint', 'errcheck'". This can be changed with the
-    |g:go_metalinter_enabled| variable. To override the command completely
-    use the variable |g:go_metalinter_command|
+    errors in a quickfix window. By default it lints the files for the path
+    `./...` . This can be changed with the 'path' argument temoporary or with the
+    |g:go_metalinter_path| variable permanently. By default the following
+    linters are enabled: "'vet', 'golint', 'errcheck'". This can be changed
+    with the |g:go_metalinter_enabled| variable. To override the command
+    completely use the variable |g:go_metalinter_command|
 
 
 ===============================================================================
@@ -846,6 +848,14 @@ over of how `gometalinter` should be executed. By default it's empty.
 >
   let g:go_metalinter_command = ""
 <
+                                                     *'g:go_metalinter_path'*
+
+Defines the default path to be linted for the |GoMetaLinter| command. By
+default it's set to `./...`, which recursively lints all files underd the
+current directory.
+>
+  let g:go_metalinter_path = "./..."
+<
 
 ===============================================================================
 TROUBLESHOOTING                                         *go-troubleshooting*

ftplugin/go/commands.vim

@@ -47,7 +47,7 @@ command! -nargs=1 -bang -complete=customlist,go#package#Complete GoImport call g
 command! -nargs=* -bang -complete=customlist,go#package#Complete GoImportAs call go#import#SwitchImport(1, <f-args>, '<bang>')
 
 " -- linters
-command! -nargs=* GoMetaLinter call go#lint#Gometa()
+command! -nargs=* GoMetaLinter call go#lint#Gometa('')
 command! -nargs=* GoLint call go#lint#Golint(<f-args>)
 command! -nargs=* -bang GoVet call go#lint#Vet(<bang>0, <f-args>)
 command! -nargs=* -complete=customlist,go#package#Complete GoErrCheck call go#lint#Errcheck(<f-args>)

ftplugin/go/mappings.vim

@@ -46,7 +46,7 @@ nnoremap <silent> <Plug>(go-doc-vertical) :<C-u>call go#doc#Open("vnew", "vsplit
 nnoremap <silent> <Plug>(go-doc-split) :<C-u>call go#doc#Open("new", "split")<CR>
 nnoremap <silent> <Plug>(go-doc-browser) :<C-u>call go#doc#OpenBrowser()<CR>
 
-nnoremap <silent> <Plug>(go-metalinter) :<C-u>call go#lint#Gometa()<CR>
+nnoremap <silent> <Plug>(go-metalinter) :<C-u>call go#lint#Gometa('')<CR>
 nnoremap <silent> <Plug>(go-vet) :<C-u>call go#lint#Vet(!g:go_jump_to_error)<CR>