vim-patch:8.2.1978: making a mapping work in all modes is complicated

Problem:    Making a mapping work in all modes is complicated.
Solution:   Add the <Cmd> special key. (Yegappan Lakshmanan, closes vim/vim#7282,
            closes 4784, based on patch by Bjorn Linse)

https://github.com/vim/vim/commit/957cf67d50516ba98716f59c9e1cb6412ec1535d

Change docs to match Vim if it's wording is better.
Change error numbers to match Vim.

Co-authored-by: Bram Moolenaar <Bram@vim.org>

6 files changed, 494 insertions, 21 deletions

diff --git a/runtime/doc/map.txt b/runtime/doc/map.txt
index 164e2d4ec5..fccb6eeb75 100644
--- a/runtime/doc/map.txt
+++ b/runtime/doc/map.txt
@@ -290,7 +290,7 @@ Therefore the following is blocked for <expr> mappings:
 - Moving the cursor is allowed, but it is restored afterwards.
 - If the cmdline is changed, the old text and cursor position are restored.
 If you want the mapping to do any of these let the returned characters do
-that. (Or use a |<Cmd>| mapping instead.)
+that, or use a |<Cmd>| mapping instead.
 
 You can use getchar(), it consumes typeahead if there is any. E.g., if you
 have these mappings: >
@@ -324,19 +324,21 @@ be seen as a special key.
 
 						*<Cmd>* *:map-cmd*
 The <Cmd> pseudokey begins a "command mapping", which executes the command
-directly (without changing modes).  Where you might use ":...<CR>" in the
+directly without changing modes.  Where you might use ":...<CR>" in the
 {rhs} of a mapping, you can instead use "<Cmd>...<CR>".
 Example: >
-	noremap x <Cmd>echo mode(1)<cr>
+	noremap x <Cmd>echo mode(1)<CR>
 <
-This is more flexible than `:<C-U>` in visual and operator-pending mode, or
-`<C-O>:` in insert-mode, because the commands are executed directly in the
-current mode (instead of always going to normal-mode).  Visual-mode is
+This is more flexible than `:<C-U>` in Visual and Operator-pending mode, or
+`<C-O>:` in Insert mode, because the commands are executed directly in the
+current mode, instead of always going to Normal mode.  Visual mode is
 preserved, so tricks with |gv| are not needed.  Commands can be invoked
-directly in cmdline-mode (which would otherwise require timer hacks).
+directly in Command-line mode (which would otherwise require timer hacks).
+Example of using <Cmd> halfway Insert mode: >
+	nnoremap <F3> aText <Cmd>echo mode(1)<CR> Added<Esc>
 
 Unlike <expr> mappings, there are no special restrictions on the <Cmd>
-command: it is executed as if an (unrestricted) |autocommand| was invoked
+command: it is executed as if an (unrestricted) |autocmd| was invoked
 or an async event event was processed.
 
 Note:
@@ -350,7 +352,7 @@ Note:
 - In Visual mode  you can use `line('v')` and `col('v')` to get one end of the
   Visual area, the cursor is at the other end.
 
-							*E5520*
+							*E1135* *E1136*
 <Cmd> commands must terminate, that is, they must be followed by <CR> in the
 {rhs} of the mapping definition.  |Command-line| mode is never entered.
 
diff --git a/src/nvim/edit.c b/src/nvim/edit.c
index 2078fc4251..c544daee08 100644
--- a/src/nvim/edit.c
+++ b/src/nvim/edit.c
@@ -876,7 +876,7 @@ static int insert_handle_key(InsertState *s)
     state_handle_k_event();
     goto check_pum;
 
-  case K_COMMAND:       // some command
+  case K_COMMAND:     // <Cmd>command<CR>
     do_cmdline(NULL, getcmdkeycmd, NULL, 0);
     goto check_pum;
 
diff --git a/src/nvim/getchar.c b/src/nvim/getchar.c
index a0e8350287..31817676e1 100644
--- a/src/nvim/getchar.c
+++ b/src/nvim/getchar.c
@@ -134,6 +134,10 @@ static size_t last_recorded_len = 0;      // number of last recorded chars
 #endif
 
 static const char e_recursive_mapping[] = N_("E223: Recursive mapping");
+static const char e_cmd_mapping_must_end_with_cr[]
+  = N_("E1135: <Cmd> mapping must end with <CR>");
+static const char e_cmd_mapping_must_end_with_cr_before_second_cmd[]
+  = N_("E1136: <Cmd> mapping must end with <CR> before second <Cmd>");
 
 // Free and clear a buffer.
 void free_buff(buffheader_T *buf)
@@ -2884,7 +2888,8 @@ int fix_input_buffer(uint8_t *buf, int len)
   return len;
 }
 
-/// Get command argument for <Cmd> key
+/// Function passed to do_cmdline() to get the command after a <Cmd> key from
+/// typeahead.
 char *getcmdkeycmd(int promptc, void *cookie, int indent, bool do_concat)
 {
   garray_T line_ga;
@@ -2894,6 +2899,7 @@ char *getcmdkeycmd(int promptc, void *cookie, int indent, bool do_concat)
 
   ga_init(&line_ga, 1, 32);
 
+  // no mapping for these characters
   no_mapping++;
 
   got_int = false;
@@ -2903,16 +2909,17 @@ char *getcmdkeycmd(int promptc, void *cookie, int indent, bool do_concat)
     if (vgetorpeek(false) == NUL) {
       // incomplete <Cmd> is an error, because there is not much the user
       // could do in this state.
-      emsg(e_cmdmap_err);
+      emsg(_(e_cmd_mapping_must_end_with_cr));
       aborted = true;
       break;
     }
 
     // Get one character at a time.
     c1 = vgetorpeek(true);
+
     // Get two extra bytes for special keys
     if (c1 == K_SPECIAL) {
-      c1 = vgetorpeek(true);          // no mapping for these chars
+      c1 = vgetorpeek(true);
       c2 = vgetorpeek(true);
       if (c1 == KS_MODIFIER) {
         cmod = c2;
@@ -2928,8 +2935,8 @@ char *getcmdkeycmd(int promptc, void *cookie, int indent, bool do_concat)
     } else if (c1 == ESC) {
       aborted = true;
     } else if (c1 == K_COMMAND) {
-      // special case to give nicer error message
-      emsg(e_cmdmap_repeated);
+      // give a nicer error message for this special case
+      emsg(_(e_cmd_mapping_must_end_with_cr_before_second_cmd));
       aborted = true;
     } else if (c1 == K_SNR) {
       ga_concat(&line_ga, "<SNR>");
diff --git a/src/nvim/globals.h b/src/nvim/globals.h
index 698f4a98c7..6eae2f7589 100644
--- a/src/nvim/globals.h
+++ b/src/nvim/globals.h
@@ -1003,10 +1003,6 @@ EXTERN const char e_cannot_edit_other_buf[] INIT(= N_("E788: Not allowed to edit
 EXTERN const char e_using_number_as_bool_nr[] INIT(= N_("E1023: Using a Number as a Bool: %d"));
 EXTERN const char e_not_callable_type_str[] INIT(= N_("E1085: Not a callable type: %s"));
 
-EXTERN const char e_cmdmap_err[] INIT(= N_("E5520: <Cmd> mapping must end with <CR>"));
-EXTERN const char e_cmdmap_repeated[]
-INIT(= N_("E5521: <Cmd> mapping must end with <CR> before second <Cmd>"));
-
 EXTERN const char e_api_error[] INIT(= N_("E5555: API call: %s"));
 
 EXTERN const char e_luv_api_disabled[] INIT(= N_("E5560: %s must not be called in a lua loop callback"));
diff --git a/test/functional/ex_cmds/cmd_map_spec.lua b/test/functional/ex_cmds/cmd_map_spec.lua
index 919d167712..a0aec7fdd0 100644
--- a/test/functional/ex_cmds/cmd_map_spec.lua
+++ b/test/functional/ex_cmds/cmd_map_spec.lua
@@ -90,7 +90,7 @@ describe('mappings with <Cmd>', function()
       {1:~                                                                }|
       {1:~                                                                }|
       {1:~                                                                }|
-      {2:E5521: <Cmd> mapping must end with <CR> before second <Cmd>}      |
+      {2:E1136: <Cmd> mapping must end with <CR> before second <Cmd>}      |
     ]])
 
     command('noremap <F3> <Cmd>let x = 3')
@@ -103,7 +103,7 @@ describe('mappings with <Cmd>', function()
       {1:~                                                                }|
       {1:~                                                                }|
       {1:~                                                                }|
-      {2:E5520: <Cmd> mapping must end with <CR>}                          |
+      {2:E1135: <Cmd> mapping must end with <CR>}                          |
     ]])
     eq(0, eval('x'))
   end)
diff --git a/test/old/testdir/test_mapping.vim b/test/old/testdir/test_mapping.vim
index e25c3c333e..b695c9e29b 100644
--- a/test/old/testdir/test_mapping.vim
+++ b/test/old/testdir/test_mapping.vim
@@ -3,6 +3,7 @@
 source shared.vim
 source check.vim
 source screendump.vim
+source term_util.vim
 
 func Test_abbreviation()
   " abbreviation with 0x80 should work
@@ -968,6 +969,473 @@ func Test_map_cpo_special_keycode()
   mapclear!
 endfunc
 
+" Test for <Cmd> key in maps to execute commands
+func Test_map_cmdkey()
+  new
+
+  " Error cases
+  let x = 0
+  noremap <F3> <Cmd><Cmd>let x = 1<CR>
+  call assert_fails('call feedkeys("\<F3>", "xt")', 'E1136:')
+  call assert_equal(0, x)
+
+  noremap <F3> <Cmd><F3>let x = 2<CR>
+  call assert_fails('call feedkeys("\<F3>", "xt")', 'E1137:')
+  call assert_equal(0, x)
+
+  noremap <F3> <Cmd>let x = 3
+  call assert_fails('call feedkeys("\<F3>", "xt!")', 'E1135:')
+  call assert_equal(0, x)
+
+  " works in various modes and sees the correct mode()
+  noremap <F3> <Cmd>let m = mode(1)<CR>
+  noremap! <F3> <Cmd>let m = mode(1)<CR>
+
+  " normal mode
+  call feedkeys("\<F3>", 'xt')
+  call assert_equal('n', m)
+
+  " visual mode
+  call feedkeys("v\<F3>", 'xt!')
+  call assert_equal('v', m)
+  " shouldn't leave the visual mode
+  call assert_equal('v', mode(1))
+  call feedkeys("\<Esc>", 'xt')
+  call assert_equal('n', mode(1))
+
+  " visual mapping in select mode
+  call feedkeys("gh\<F3>", 'xt!')
+  call assert_equal('v', m)
+  " shouldn't leave select mode
+  call assert_equal('s', mode(1))
+  call feedkeys("\<Esc>", 'xt')
+  call assert_equal('n', mode(1))
+
+  " select mode mapping
+  snoremap <F3> <Cmd>let m = mode(1)<cr>
+  call feedkeys("gh\<F3>", 'xt!')
+  call assert_equal('s', m)
+  " shouldn't leave select mode
+  call assert_equal('s', mode(1))
+  call feedkeys("\<Esc>", 'xt')
+  call assert_equal('n', mode(1))
+
+  " operator-pending mode
+  call feedkeys("d\<F3>", 'xt!')
+  call assert_equal('no', m)
+  " leaves the operator-pending mode
+  call assert_equal('n', mode(1))
+
+  " insert mode
+  call feedkeys("i\<F3>abc", 'xt')
+  call assert_equal('i', m)
+  call assert_equal('abc', getline('.'))
+
+  " replace mode
+  call feedkeys("0R\<F3>two", 'xt')
+  call assert_equal('R', m)
+  call assert_equal('two', getline('.'))
+
+  " virtual replace mode
+  call setline('.', "one\ttwo")
+  call feedkeys("4|gR\<F3>xxx", 'xt')
+  call assert_equal('Rv', m)
+  call assert_equal("onexxx\ttwo", getline('.'))
+
+  " cmdline mode
+  call feedkeys(":\<F3>\"xxx\<CR>", 'xt!')
+  call assert_equal('c', m)
+  call assert_equal('"xxx', @:)
+
+  " terminal mode
+  if CanRunVimInTerminal()
+    tnoremap <F3> <Cmd>let m = mode(1)<CR>
+    let buf = Run_shell_in_terminal({})
+    call feedkeys("\<F3>", 'xt')
+    call assert_equal('t', m)
+    call assert_equal('t', mode(1))
+    call StopShellInTerminal(buf)
+    call TermWait(buf)
+    close!
+    tunmap <F3>
+  endif
+
+  " invoke cmdline mode recursively
+  noremap! <F2> <Cmd>norm! :foo<CR>
+  %d
+  call setline(1, ['some short lines', 'of test text'])
+  call feedkeys(":bar\<F2>x\<C-B>\"\r", 'xt')
+  call assert_equal('"barx', @:)
+  unmap! <F2>
+
+  " test for calling a <SID> function
+  let lines =<< trim END
+    map <F2> <Cmd>call <SID>do_it()<CR>
+    func s:do_it()
+      let g:x = 32
+    endfunc
+  END
+  call writefile(lines, 'Xscript')
+  source Xscript
+  call feedkeys("\<F2>", 'xt')
+  call assert_equal(32, g:x)
+  call delete('Xscript')
+
+  unmap <F3>
+  unmap! <F3>
+  %bw!
+endfunc
+
+" text object enters visual mode
+func TextObj()
+  if mode() !=# "v"
+    normal! v
+  end
+  call cursor(1, 3)
+  normal! o
+  call cursor(2, 4)
+endfunc
+
+func s:cmdmap(lhs, rhs)
+  exe 'noremap ' .. a:lhs .. ' <Cmd>' .. a:rhs .. '<CR>'
+  exe 'noremap! ' .. a:lhs .. ' <Cmd>' .. a:rhs .. '<CR>'
+endfunc
+
+func s:cmdunmap(lhs)
+  exe 'unmap ' .. a:lhs
+  exe 'unmap! ' .. a:lhs
+endfunc
+
+" Map various <Fx> keys used by the <Cmd> key tests
+func s:setupMaps()
+  call s:cmdmap('<F3>', 'let m = mode(1)')
+  call s:cmdmap('<F4>', 'normal! ww')
+  call s:cmdmap('<F5>', 'normal! "ay')
+  call s:cmdmap('<F6>', 'throw "very error"')
+  call s:cmdmap('<F7>', 'call TextObj()')
+  call s:cmdmap('<F8>', 'startinsert')
+  call s:cmdmap('<F9>', 'stopinsert')
+endfunc
+
+" Remove the mappings setup by setupMaps()
+func s:cleanupMaps()
+  call s:cmdunmap('<F3>')
+  call s:cmdunmap('<F4>')
+  call s:cmdunmap('<F5>')
+  call s:cmdunmap('<F6>')
+  call s:cmdunmap('<F7>')
+  call s:cmdunmap('<F8>')
+  call s:cmdunmap('<F9>')
+endfunc
+
+" Test for <Cmd> mapping in normal mode
+func Test_map_cmdkey_normal_mode()
+  new
+  call s:setupMaps()
+
+  " check v:count and v:register works
+  call s:cmdmap('<F2>', 'let s = [mode(1), v:count, v:register]')
+  call feedkeys("\<F2>", 'xt')
+  call assert_equal(['n', 0, '"'], s)
+  call feedkeys("7\<F2>", 'xt')
+  call assert_equal(['n', 7, '"'], s)
+  call feedkeys("\"e\<F2>", 'xt')
+  call assert_equal(['n', 0, 'e'], s)
+  call feedkeys("5\"k\<F2>", 'xt')
+  call assert_equal(['n', 5, 'k'], s)
+  call s:cmdunmap('<F2>')
+
+  call setline(1, ['some short lines', 'of test text'])
+  call feedkeys("\<F7>y", 'xt')
+  call assert_equal("me short lines\nof t", @")
+  call assert_equal('v', getregtype('"'))
+  call assert_equal([0, 1, 3, 0], getpos("'<"))
+  call assert_equal([0, 2, 4, 0], getpos("'>"))
+
+  " startinsert
+  %d
+  call feedkeys("\<F8>abc", 'xt')
+  call assert_equal('abc', getline(1))
+
+  " feedkeys are not executed immediately
+  noremap ,a <Cmd>call feedkeys("aalpha") \| let g:a = getline(2)<CR>
+  %d
+  call setline(1, ['some short lines', 'of test text'])
+  call cursor(2, 3)
+  call feedkeys(",a\<F3>", 'xt')
+  call assert_equal('of test text', g:a)
+  call assert_equal('n', m)
+  call assert_equal(['some short lines', 'of alphatest text'], getline(1, '$'))
+  nunmap ,a
+
+  " feedkeys(..., 'x') is executed immediately, but insert mode is aborted
+  noremap ,b <Cmd>call feedkeys("abeta", 'x') \| let g:b = getline(2)<CR>
+  call feedkeys(",b\<F3>", 'xt')
+  call assert_equal('n', m)
+  call assert_equal('of alphabetatest text', g:b)
+  nunmap ,b
+
+  call s:cleanupMaps()
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping with the :normal command
+func Test_map_cmdkey_normal_cmd()
+  new
+  noremap ,x <Cmd>call append(1, "xx") \| call append(1, "aa")<CR>
+  noremap ,f <Cmd>nosuchcommand<CR>
+  noremap ,e <Cmd>throw "very error" \| call append(1, "yy")<CR>
+  noremap ,m <Cmd>echoerr "The message." \| call append(1, "zz")<CR>
+  noremap ,w <Cmd>for i in range(5) \| if i==1 \| echoerr "Err" \| endif \| call append(1, i) \| endfor<CR>
+
+  call setline(1, ['some short lines', 'of test text'])
+  exe "norm ,x\r"
+  call assert_equal(['some short lines', 'aa', 'xx', 'of test text'], getline(1, '$'))
+
+  call assert_fails('norm ,f', 'E492:')
+  call assert_fails('norm ,e', 'very error')
+  call assert_fails('norm ,m', 'The message.')
+  call assert_equal(['some short lines', 'aa', 'xx', 'of test text'], getline(1, '$'))
+
+  %d
+  let caught_err = 0
+  try
+    exe "normal ,w"
+  catch /Vim(echoerr):Err/
+    let caught_err = 1
+  endtry
+  call assert_equal(1, caught_err)
+  call assert_equal(['', '0'], getline(1, '$'))
+
+  %d
+  call assert_fails('normal ,w', 'Err')
+  call assert_equal(['', '4', '3', '2' ,'1', '0'], getline(1, '$'))
+  call assert_equal(1, line('.'))
+
+  nunmap ,x
+  nunmap ,f
+  nunmap ,e
+  nunmap ,m
+  nunmap ,w
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in visual mode
+func Test_map_cmdkey_visual_mode()
+  new
+  set showmode
+  call s:setupMaps()
+
+  call setline(1, ['some short lines', 'of test text'])
+  call feedkeys("v\<F4>", 'xt!')
+  call assert_equal(['v', 1, 12], [mode(1), col('v'), col('.')])
+
+  " can invoke an opeartor, ending the visual mode
+  let @a = ''
+  call feedkeys("\<F5>", 'xt!')
+  call assert_equal('n', mode(1))
+  call assert_equal('some short l', @a)
+
+  " error doesn't interrupt visual mode
+  call assert_fails('call feedkeys("ggvw\<F6>", "xt!")', 'E605:')
+  call assert_equal(['v', 1, 6], [mode(1), col('v'), col('.')])
+  call feedkeys("\<F7>", 'xt!')
+  call assert_equal(['v', 1, 3, 2, 4], [mode(1), line('v'), col('v'), line('.'), col('.')])
+
+  " startinsert gives "-- (insert) VISUAL --" mode
+  call feedkeys("\<F8>", 'xt!')
+  call assert_equal(['v', 1, 3, 2, 4], [mode(1), line('v'), col('v'), line('.'), col('.')])
+  redraw!
+  call assert_match('^-- (insert) VISUAL --', Screenline(&lines))
+  call feedkeys("\<Esc>new ", 'x')
+  call assert_equal(['some short lines', 'of new test text'], getline(1, '$'))
+
+  call s:cleanupMaps()
+  set showmode&
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in select mode
+func Test_map_cmdkey_select_mode()
+  new
+  set showmode
+  call s:setupMaps()
+
+  snoremap <F1> <cmd>throw "very error"<CR>
+  snoremap <F2> <cmd>normal! <c-g>"by<CR>
+  call setline(1, ['some short lines', 'of test text'])
+
+  call feedkeys("gh\<F4>", "xt!")
+  call assert_equal(['s', 1, 12], [mode(1), col('v'), col('.')])
+  redraw!
+  call assert_match('^-- SELECT --', Screenline(&lines))
+
+  " visual mapping in select mode restarts select mode after operator
+  let @a = ''
+  call feedkeys("\<F5>", 'xt!')
+  call assert_equal('s', mode(1))
+  call assert_equal('some short l', @a)
+
+  " select mode mapping works, and does not restart select mode
+  let @b = ''
+  call feedkeys("\<F2>", 'xt!')
+  call assert_equal('n', mode(1))
+  call assert_equal('some short l', @b)
+
+  " error doesn't interrupt temporary visual mode
+  call assert_fails('call feedkeys("\<Esc>ggvw\<C-G>\<F6>", "xt!")', 'E605:')
+  redraw!
+  call assert_match('^-- VISUAL --', Screenline(&lines))
+  " quirk: restoration of select mode is not performed
+  call assert_equal(['v', 1, 6], [mode(1), col('v'), col('.')])
+
+  " error doesn't interrupt select mode
+  call assert_fails('call feedkeys("\<Esc>ggvw\<C-G>\<F1>", "xt!")', 'E605:')
+  redraw!
+  call assert_match('^-- SELECT --', Screenline(&lines))
+  call assert_equal(['s', 1, 6], [mode(1), col('v'), col('.')])
+
+  call feedkeys("\<F7>", 'xt!')
+  redraw!
+  call assert_match('^-- SELECT --', Screenline(&lines))
+  call assert_equal(['s', 1, 3, 2, 4], [mode(1), line('v'), col('v'), line('.'), col('.')])
+
+  " startinsert gives "-- SELECT (insert) --" mode
+  call feedkeys("\<F8>", 'xt!')
+  redraw!
+  call assert_match('^-- (insert) SELECT --', Screenline(&lines))
+  call assert_equal(['s', 1, 3, 2, 4], [mode(1), line('v'), col('v'), line('.'), col('.')])
+  call feedkeys("\<Esc>new ", 'x')
+  call assert_equal(['some short lines', 'of new test text'], getline(1, '$'))
+
+  sunmap <F1>
+  sunmap <F2>
+  call s:cleanupMaps()
+  set showmode&
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in operator-pending mode
+func Test_map_cmdkey_op_pending_mode()
+  new
+  call s:setupMaps()
+
+  call setline(1, ['some short lines', 'of test text'])
+  call feedkeys("d\<F4>", 'xt')
+  call assert_equal(['lines', 'of test text'], getline(1, '$'))
+  call assert_equal(['some short '], getreg('"', 1, 1))
+  " create a new undo point
+  let &undolevels = &undolevels
+
+  call feedkeys(".", 'xt')
+  call assert_equal(['test text'], getline(1, '$'))
+  call assert_equal(['lines', 'of '], getreg('"', 1, 1))
+  " create a new undo point
+  let &undolevels = &undolevels
+
+  call feedkeys("uu", 'xt')
+  call assert_equal(['some short lines', 'of test text'], getline(1, '$'))
+
+  " error aborts operator-pending, operator not performed
+  call assert_fails('call feedkeys("d\<F6>", "xt")', 'E605:')
+  call assert_equal(['some short lines', 'of test text'], getline(1, '$'))
+
+  call feedkeys("\"bd\<F7>", 'xt')
+  call assert_equal(['soest text'], getline(1, '$'))
+  call assert_equal(['me short lines', 'of t'], getreg('b', 1, 1))
+
+  " startinsert aborts operator
+  call feedkeys("d\<F8>cc", 'xt')
+  call assert_equal(['soccest text'], getline(1, '$'))
+
+  call s:cleanupMaps()
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in insert mode
+func Test_map_cmdkey_insert_mode()
+  new
+  call s:setupMaps()
+
+  call setline(1, ['some short lines', 'of test text'])
+  " works the same as <C-O>w<C-O>w
+  call feedkeys("iindeed \<F4>little ", 'xt')
+  call assert_equal(['indeed some short little lines', 'of test text'], getline(1, '$'))
+  call assert_fails('call feedkeys("i\<F6> 2", "xt")', 'E605:')
+  call assert_equal(['indeed some short little 2 lines', 'of test text'], getline(1, '$'))
+
+  " Note when entering visual mode from InsertEnter autocmd, an async event,
+  " or a <Cmd> mapping, vim ends up in undocumented "INSERT VISUAL" mode.
+  call feedkeys("i\<F7>stuff ", 'xt')
+  call assert_equal(['indeed some short little 2 lines', 'of stuff test text'], getline(1, '$'))
+  call assert_equal(['v', 1, 3, 2, 9], [mode(1), line('v'), col('v'), line('.'), col('.')])
+
+  call feedkeys("\<F5>", 'xt')
+  call assert_equal(['deed some short little 2 lines', 'of stuff '], getreg('a', 1, 1))
+
+  " also works as part of abbreviation
+  abbr foo <Cmd>let g:y = 17<CR>bar
+  exe "normal i\<space>foo "
+  call assert_equal(17, g:y)
+  call assert_equal('in bar deed some short little 2 lines', getline(1))
+  unabbr foo
+
+  " :startinsert does nothing
+  call setline(1, 'foo bar')
+  call feedkeys("ggi\<F8>vim", 'xt')
+  call assert_equal('vimfoo bar', getline(1))
+
+  " :stopinsert works
+  call feedkeys("ggi\<F9>Abc", 'xt')
+  call assert_equal('vimfoo barbc', getline(1))
+
+  call s:cleanupMaps()
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in insert-completion mode
+func Test_map_cmdkey_insert_complete_mode()
+  new
+  call s:setupMaps()
+
+  call setline(1, 'some short lines')
+  call feedkeys("os\<C-X>\<C-N>\<F3>\<C-N> ", 'xt')
+  call assert_equal('ic', m)
+  call assert_equal(['some short lines', 'short '], getline(1, '$'))
+
+  call s:cleanupMaps()
+  %bw!
+endfunc
+
+" Test for <Cmd> mapping in cmdline mode
+func Test_map_cmdkey_cmdline_mode()
+  new
+  call s:setupMaps()
+
+  call setline(1, ['some short lines', 'of test text'])
+  let x = 0
+  call feedkeys(":let x\<F3>= 10\r", 'xt')
+  call assert_equal('c', m)
+  call assert_equal(10, x)
+
+  " exception doesn't leave cmdline mode
+  call assert_fails('call feedkeys(":let x\<F6>= 20\r", "xt")', 'E605:')
+  call assert_equal(20, x)
+
+  " move cursor in the buffer from cmdline mode
+  call feedkeys(":let x\<F4>= 30\r", 'xt')
+  call assert_equal(30, x)
+  call assert_equal(12, col('.'))
+
+  " :startinsert takes effect after leaving cmdline mode
+  call feedkeys(":let x\<F8>= 40\rnew ", 'xt')
+  call assert_equal(40, x)
+  call assert_equal('some short new lines', getline(1))
+
+  call s:cleanupMaps()
+  %bw!
+endfunc
+
 func Test_map_cmdkey_redo()
   func SelectDash()
     call search('^---\n\zs', 'bcW')