vim-patch:8.2.0698: insert mode completion not fully tested

Problem:    Insert mode completion not fully tested.
Solution:   Add a few more tests. (Yegappan Lakshmanan, closes vim/vim#6041)
https://github.com/vim/vim/commit/f9ab52e155dc13f59b654d754041fe78e17b9074

Cherry-pick test_ins_complete.vim changes from patches 8.2.{0522,0615}.

3 files changed, 115 insertions, 9 deletions

diff --git a/src/nvim/testdir/test_edit.vim b/src/nvim/testdir/test_edit.vim
index 69a34a1c51..42c77518e4 100644
--- a/src/nvim/testdir/test_edit.vim
+++ b/src/nvim/testdir/test_edit.vim
@@ -349,8 +349,8 @@ func Test_edit_11_indentexpr()
   bw!
 endfunc
 
+" Test changing indent in replace mode
 func Test_edit_12()
-  " Test changing indent in replace mode
   new
   call setline(1, ["\tabc", "\tdef"])
   call cursor(2, 4)
@@ -389,15 +389,15 @@ func Test_edit_12()
   call feedkeys("R\<c-t>\<c-t>", 'tnix')
   call assert_equal(["\tabc", "\t\t\tdef"], getline(1, '$'))
   call assert_equal([0, 2, 2, 0], getpos('.'))
-  set et
-  set sw& et&
+  set sw&
+
+  " In replace mode, after hitting enter in a line with tab characters,
+  " pressing backspace should restore the tab characters.
   %d
-  call setline(1, ["\t/*"])
-  set formatoptions=croql
-  call cursor(1, 3)
-  call feedkeys("A\<cr>\<cr>/", 'tnix')
-  call assert_equal(["\t/*", " *", " */"], getline(1, '$'))
-  set formatoptions&
+  setlocal autoindent backspace=2
+  call setline(1, "\tone\t\ttwo")
+  exe "normal ggRred\<CR>six" .. repeat("\<BS>", 8)
+  call assert_equal(["\tone\t\ttwo"], getline(1, '$'))
   bw!
 endfunc
 
diff --git a/src/nvim/testdir/test_ins_complete.vim b/src/nvim/testdir/test_ins_complete.vim
index 4b444d15d8..4fcf35c00f 100644
--- a/src/nvim/testdir/test_ins_complete.vim
+++ b/src/nvim/testdir/test_ins_complete.vim
@@ -601,6 +601,88 @@ func Test_ins_compl_tag_sft()
   %bwipe!
 endfunc
 
+" Test for 'completefunc' deleting text
+func Test_completefunc_error()
+  new
+  " delete text when called for the first time
+  func CompleteFunc(findstart, base)
+    if a:findstart == 1
+      normal dd
+      return col('.') - 1
+    endif
+    return ['a', 'b']
+  endfunc
+  set completefunc=CompleteFunc
+  call setline(1, ['', 'abcd', ''])
+  call assert_fails('exe "normal 2G$a\<C-X>\<C-U>"', 'E840:')
+
+  " delete text when called for the second time
+  func CompleteFunc2(findstart, base)
+    if a:findstart == 1
+      return col('.') - 1
+    endif
+    normal dd
+    return ['a', 'b']
+  endfunc
+  set completefunc=CompleteFunc2
+  call setline(1, ['', 'abcd', ''])
+  call assert_fails('exe "normal 2G$a\<C-X>\<C-U>"', 'E565:')
+
+  " Jump to a different window from the complete function
+  " TODO: The following test causes an ASAN failure. Once this issue is
+  " addressed, enable the following test.
+  "func! CompleteFunc(findstart, base)
+  "  if a:findstart == 1
+  "    return col('.') - 1
+  "  endif
+  "  wincmd p
+  "  return ['a', 'b']
+  "endfunc
+  "set completefunc=CompleteFunc
+  "new
+  "call assert_fails('exe "normal a\<C-X>\<C-U>"', 'E839:')
+  "close!
+
+  set completefunc&
+  delfunc CompleteFunc
+  delfunc CompleteFunc2
+  close!
+endfunc
+
+" Test for returning non-string values from 'completefunc'
+func Test_completefunc_invalid_data()
+  new
+  func! CompleteFunc(findstart, base)
+    if a:findstart == 1
+      return col('.') - 1
+    endif
+    return [{}, '', 'moon']
+  endfunc
+  set completefunc=CompleteFunc
+  exe "normal i\<C-X>\<C-U>"
+  call assert_equal('moon', getline(1))
+  set completefunc&
+  close!
+endfunc
+
+" Test for errors in using complete() function
+func Test_complete_func_error()
+  call assert_fails('call complete(1, ["a"])', 'E785:')
+  func ListColors()
+    call complete(col('.'), "blue")
+  endfunc
+  call assert_fails('exe "normal i\<C-R>=ListColors()\<CR>"', 'E474:')
+  func ListMonths()
+    call complete(col('.'), test_null_list())
+  endfunc
+  " Nvim allows a NULL list
+  " call assert_fails('exe "normal i\<C-R>=ListMonths()\<CR>"', 'E474:')
+  delfunc ListColors
+  delfunc ListMonths
+  call assert_fails('call complete_info({})', 'E714:')
+  call assert_equal([], complete_info(['items']).items)
+endfunc
+
 " Test for completing words following a completed word in a line
 func Test_complete_wrapscan()
   " complete words from another buffer
diff --git a/src/nvim/testdir/test_textformat.vim b/src/nvim/testdir/test_textformat.vim
index 35a7887761..970f5ae0d0 100644
--- a/src/nvim/testdir/test_textformat.vim
+++ b/src/nvim/testdir/test_textformat.vim
@@ -1161,6 +1161,30 @@ func Test_whichwrap_multi_byte()
   bwipe!
 endfunc
 
+" Test for automatically adding comment leaders in insert mode
+func Test_threepiece_comment()
+  new
+  setlocal expandtab
+  call setline(1, ["\t/*"])
+  setlocal formatoptions=croql
+  call cursor(1, 3)
+  call feedkeys("A\<cr>\<cr>/", 'tnix')
+  call assert_equal(["\t/*", " *", " */"], getline(1, '$'))
+
+  " If a comment ends in a single line, then don't add it in the next line
+  %d
+  call setline(1, '/* line1 */')
+  call feedkeys("A\<CR>next line", 'xt')
+  call assert_equal(['/* line1 */', 'next line'], getline(1, '$'))
+
+  %d
+  " Copy the trailing indentation from the leader comment to a new line
+  setlocal autoindent noexpandtab
+  call feedkeys("a\t/*\tone\ntwo\n/", 'xt')
+  call assert_equal(["\t/*\tone", "\t *\ttwo", "\t */"], getline(1, '$'))
+  close!
+endfunc
+
 " Test for the 'f' flag in 'comments' (only the first line has the comment
 " string)
 func Test_firstline_comment()