vim-patch:8.1.0716: get warning message when 'completefunc' returns nothing

Problem:    Get warning message when 'completefunc' returns nothing.
Solution:   Allow for returning v:none to suppress the warning message.
            (Yasuhiro Matsumoto, closes vim/vim#3789)
https://github.com/vim/vim/commit/cee9bc2e3dc5c16a9d2a8d0e23aa0d5fdefa3a4a

2 files changed, 47 insertions, 18 deletions

diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index cdb4b127da..9bc00cf2aa 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -3747,6 +3747,8 @@ expand_by_function(
     case VAR_DICT:
       matchdict = rettv.vval.v_dict;
       break;
+    case VAR_SPECIAL:
+      FALLTHROUGH;
     default:
       // TODO(brammool): Give error message?
       tv_clear(&rettv);
@@ -5210,7 +5212,7 @@ static int ins_complete(int c, bool enable_pum)
     }
   }
 
-  /* Show a message about what (completion) mode we're in. */
+  // Show a message about what (completion) mode we're in.
   showmode();
   if (!shortmess(SHM_COMPLETIONMENU)) {
     if (edit_submode_extra != NULL) {
diff --git a/src/nvim/testdir/test_ins_complete.vim b/src/nvim/testdir/test_ins_complete.vim
index 52ec281d82..e77afb7a55 100644
--- a/src/nvim/testdir/test_ins_complete.vim
+++ b/src/nvim/testdir/test_ins_complete.vim
@@ -98,6 +98,15 @@ func Test_ins_complete()
   call delete('Xdir', 'rf')
 endfunc
 
+func s:CompleteDone_CompleteFuncNone( findstart, base )
+  throw 'skipped: Nvim does not support v:none'
+  if a:findstart
+    return 0
+  endif
+
+  return v:none
+endfunc
+
 function! s:CompleteDone_CompleteFuncDict( findstart, base )
   if a:findstart
     return 0
@@ -117,6 +126,10 @@ function! s:CompleteDone_CompleteFuncDict( findstart, base )
         \ }
 endfunction
 
+func s:CompleteDone_CheckCompletedItemNone()
+  let s:called_completedone = 1
+endfunc
+
 function! s:CompleteDone_CheckCompletedItemDict()
   call assert_equal( 'aword',          v:completed_item[ 'word' ] )
   call assert_equal( 'wrd',            v:completed_item[ 'abbr' ] )
@@ -128,15 +141,29 @@ function! s:CompleteDone_CheckCompletedItemDict()
   let s:called_completedone = 1
 endfunction
 
-function Test_CompleteDoneDict()
+func Test_CompleteDoneNone()
+  throw 'skipped: Nvim does not support v:none'
+  au CompleteDone * :call <SID>CompleteDone_CheckCompletedItemNone()
+
+  set completefunc=<SID>CompleteDone_CompleteFuncNone
+  execute "normal a\<C-X>\<C-U>\<C-Y>"
+  set completefunc&
+
+  call assert_true(s:called_completedone)
+
+  let s:called_completedone = 0
+  au! CompleteDone
+endfunc
+
+func Test_CompleteDoneDict()
   au CompleteDone * :call <SID>CompleteDone_CheckCompletedItemDict()
 
   set completefunc=<SID>CompleteDone_CompleteFuncDict
   execute "normal a\<C-X>\<C-U>\<C-Y>"
   set completefunc&
 
-  call assert_equal( 'test', v:completed_item[ 'user_data' ] )
-  call assert_true( s:called_completedone )
+  call assert_equal('test', v:completed_item[ 'user_data' ])
+  call assert_true(s:called_completedone)
 
   let s:called_completedone = 0
   au! CompleteDone
@@ -155,7 +182,7 @@ func Test_CompleteDone_undo()
   au! CompleteDone
 endfunc
 
-function! s:CompleteDone_CompleteFuncDictNoUserData( findstart, base )
+func s:CompleteDone_CompleteFuncDictNoUserData(findstart, base)
   if a:findstart
     return 0
   endif
@@ -171,9 +198,9 @@ function! s:CompleteDone_CompleteFuncDictNoUserData( findstart, base )
             \ }
           \ ]
         \ }
-endfunction
+endfunc
 
-function! s:CompleteDone_CheckCompletedItemDictNoUserData()
+func s:CompleteDone_CheckCompletedItemDictNoUserData()
   call assert_equal( 'aword',          v:completed_item[ 'word' ] )
   call assert_equal( 'wrd',            v:completed_item[ 'abbr' ] )
   call assert_equal( 'extra text',     v:completed_item[ 'menu' ] )
@@ -182,31 +209,31 @@ function! s:CompleteDone_CheckCompletedItemDictNoUserData()
   call assert_equal( '',               v:completed_item[ 'user_data' ] )
 
   let s:called_completedone = 1
-endfunction
+endfunc
 
-function Test_CompleteDoneDictNoUserData()
+func Test_CompleteDoneDictNoUserData()
   au CompleteDone * :call <SID>CompleteDone_CheckCompletedItemDictNoUserData()
 
   set completefunc=<SID>CompleteDone_CompleteFuncDictNoUserData
   execute "normal a\<C-X>\<C-U>\<C-Y>"
   set completefunc&
 
-  call assert_equal( '', v:completed_item[ 'user_data' ] )
-  call assert_true( s:called_completedone )
+  call assert_equal('', v:completed_item[ 'user_data' ])
+  call assert_true(s:called_completedone)
 
   let s:called_completedone = 0
   au! CompleteDone
 endfunc
 
-function! s:CompleteDone_CompleteFuncList( findstart, base )
+func s:CompleteDone_CompleteFuncList(findstart, base)
   if a:findstart
     return 0
   endif
 
   return [ 'aword' ]
-endfunction
+endfunc
 
-function! s:CompleteDone_CheckCompletedItemList()
+func s:CompleteDone_CheckCompletedItemList()
   call assert_equal( 'aword', v:completed_item[ 'word' ] )
   call assert_equal( '',      v:completed_item[ 'abbr' ] )
   call assert_equal( '',      v:completed_item[ 'menu' ] )
@@ -215,17 +242,17 @@ function! s:CompleteDone_CheckCompletedItemList()
   call assert_equal( '',      v:completed_item[ 'user_data' ] )
 
   let s:called_completedone = 1
-endfunction
+endfunc
 
-function Test_CompleteDoneList()
+func Test_CompleteDoneList()
   au CompleteDone * :call <SID>CompleteDone_CheckCompletedItemList()
 
   set completefunc=<SID>CompleteDone_CompleteFuncList
   execute "normal a\<C-X>\<C-U>\<C-Y>"
   set completefunc&
 
-  call assert_equal( '', v:completed_item[ 'user_data' ] )
-  call assert_true( s:called_completedone )
+  call assert_equal('', v:completed_item[ 'user_data' ])
+  call assert_true(s:called_completedone)
 
   let s:called_completedone = 0
   au! CompleteDone