Add :GoExpandErr

autoload/go/expanderr.vim

@@ -0,0 +1,34 @@
+function! go#expanderr#ExpandErr() abort
+  let binpath = go#path#CheckBinPath('expanderr')
+  if empty(binpath)
+    return
+  endif
+
+  let l:cmd = [binpath, '-format', 'json',
+        \ bufname('') . ':#' . go#util#OffsetCursor()]
+
+  let l:out = go#util#System(go#util#Shelljoin(l:cmd))
+  if go#util#ShellError() != 0
+    call go#util#EchoError(l:out)
+    return
+  endif
+
+  try
+    let l:json = json_decode(l:out)
+  catch
+    call go#util#EchoError(l:out)
+    return
+  endtry
+
+  let l:code = l:json['lines']
+  let l:pos = getpos('.')
+
+  try
+    call setline('.', l:code[0])
+    call append('.', l:code[1:])
+  finally
+    call setpos('.', l:pos)
+  endtry
+endfunction
+
+" vim: sw=2 ts=2 et

doc/vim-go.txt

@@ -810,7 +810,7 @@ CTRL-t
     Becomes:
 >
       addr := net.Address{
-        Name: "Ford Prefect",
+        Name:  "Ford Prefect",
         Email: "",
       }
 <

ftplugin/go/commands.vim

@@ -107,4 +107,7 @@ command! -nargs=0 GoKeyify call go#keyify#Keyify()
 " -- fillstruct
 command! -nargs=0 GoFillStruct call go#fillstruct#FillStruct()
 
+" -- expanderr
+command! -nargs=0 GoExpandErr call go#expanderr#ExpandErr()
+
 " vim: sw=2 ts=2 et