feat(defaults): mouse=nvi #19290

Problem:
Since right-click can now show a popup menu, we can provide messaging to
guide users who expect 'mouse' to be disabled by default. So 'mouse' can
now be enabled by default.

Solution:
Do it.
Closes #15521

14 files changed, 106 insertions, 34 deletions

diff --git a/runtime/doc/gui.txt b/runtime/doc/gui.txt
index 5badd954d9..776ff228d6 100644
--- a/runtime/doc/gui.txt
+++ b/runtime/doc/gui.txt
@@ -441,6 +441,19 @@ You can define the special menu "PopUp".  This is the menu that is displayed
 when the right mouse button is pressed, if 'mousemodel' is set to popup or
 popup_setpos.
 
+The default "PopUp" menu is: >
+    aunmenu PopUp
+    vnoremenu PopUp.Cut                         "+x
+    vnoremenu PopUp.Copy                        "+y
+    anoremenu PopUp.Paste                       "+gP
+    vnoremenu PopUp.Paste                       "+P
+    vnoremenu PopUp.Delete                      "_x
+    nnoremenu PopUp.Select\ All>                ggVG
+    vnoremenu PopUp.Select\ All>                gg0oG$
+    inoremenu PopUp.Select\ All                 <C-Home><C-O>VG
+    anoremenu PopUp.-1-                         <Nop>
+    anoremenu PopUp.How-to\ disable\ mouse      <Cmd>help disable-mouse<CR>
+<
 
 Showing What Menus Are Mapped To			*showing-menus*
 
diff --git a/runtime/doc/options.txt b/runtime/doc/options.txt
index 74ba353e0a..0f1c2051a6 100644
--- a/runtime/doc/options.txt
+++ b/runtime/doc/options.txt
@@ -4086,7 +4086,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	listing continues until finished.
 
 						*'mouse'*
-'mouse'			string	(default "")
+'mouse'			string	(default "nvi")
 			global
 
 	Enables mouse support. For example, to enable the mouse in Normal mode
@@ -4158,7 +4158,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	The mouse pointer is restored when the mouse is moved.
 
 						*'mousemodel'* *'mousem'*
-'mousemodel' 'mousem'	string	(default "extend")
+'mousemodel' 'mousem'	string	(default "popup_setpos")
 			global
 	Sets the model to use for the mouse.  The name mostly specifies what
 	the right mouse button is used for:
@@ -4184,7 +4184,7 @@ A jump table for the options with a short description can be found at |Q_op|.
 	middle click	    paste		paste
 
 	In the "popup" model the right mouse button produces a pop-up menu.
-	You need to define this first, see |popup-menu|.
+	Nvim creates a default |popup-menu| but you can redefine it.
 
 	Note that you can further refine the meaning of buttons with mappings.
 	See |mouse-overview|.  But mappings are NOT used for modeless selection.
diff --git a/runtime/doc/starting.txt b/runtime/doc/starting.txt
index 108a47c522..d57a85423c 100644
--- a/runtime/doc/starting.txt
+++ b/runtime/doc/starting.txt
@@ -407,7 +407,7 @@ accordingly, proceeding as follows:
 	Nvim started with |--embed| waits for the UI to connect before
 	proceeding to load user configuration.
 
-4. Setup |default-mappings| and  |default-autocmds|.
+4. Setup |default-mappings| and |default-autocmds|.  Create |popup-menu|.
 
 5. Enable filetype and indent plugins.
 	This does the same as the command: >
diff --git a/runtime/doc/vim_diff.txt b/runtime/doc/vim_diff.txt
index bacf160206..a74149d050 100644
--- a/runtime/doc/vim_diff.txt
+++ b/runtime/doc/vim_diff.txt
@@ -52,6 +52,8 @@ centralized reference of the differences.
 - 'langremap' is disabled
 - 'laststatus' defaults to 2 (statusline is always shown)
 - 'listchars' defaults to "tab:> ,trail:-,nbsp:+"
+- 'mouse' defaults to "nvi"
+- 'mousemodel' defaults to "popup_setpos"
 - 'nrformats' defaults to "bin,hex"
 - 'ruler' is enabled
 - 'sessionoptions' includes "unix,slash", excludes "options"
@@ -78,6 +80,30 @@ centralized reference of the differences.
 - |g:vimsyn_embed| defaults to "l" to enable Lua highlighting
 
 
+Default Mouse ~
+						*default-mouse* *disable-mouse*
+By default the mouse is enabled.  The right button click opens |popup-menu|
+with standard actions, such as "Cut", "Copy" and "Paste".
+
+If you don't like this you can add to your |config| any of the following:
+
+- ignore mouse completely >
+  set mouse=
+<
+- no |popup-menu| but the right button extends selection >
+  set mousemodel=extend
+>
+- pressing ALT+LeftMouse releases mouse until main cursor moves  >
+  nnoremap <M-LeftMouse> <Cmd>
+    \ set mouse=<Bar>
+    \ echo 'mouse OFF until next cursor-move'<Bar>
+    \ autocmd CursorMoved * ++once set mouse&<Bar>
+    \ echo 'mouse ON'<CR>
+<
+Also, mouse is not in use in |command-mode| or at |more-prompt|.  So if you
+need to copy/paste with your terminal then just pressing ':' makes Nvim to
+release the mouse cursor temporarily.
+
 Default Mappings ~
 							*default-mappings*
 Nvim creates the following default mappings at |startup|. You can disable any
diff --git a/runtime/lua/vim/_editor.lua b/runtime/lua/vim/_editor.lua
index 7febad6ef6..c4cc151bca 100644
--- a/runtime/lua/vim/_editor.lua
+++ b/runtime/lua/vim/_editor.lua
@@ -810,6 +810,44 @@ function vim.deprecate(name, alternative, version, plugin, backtrace)
   end
 end
 
+--- Create builtin mappings (incl. menus).
+--- Called once on startup.
+function vim._init_default_mappings()
+  -- mappings
+
+  --@private
+  local function map(mode, lhs, rhs)
+    vim.api.nvim_set_keymap(mode, lhs, rhs, { noremap = true, desc = 'Nvim builtin' })
+  end
+
+  map('n', 'Y', 'y$')
+  -- Use normal! <C-L> to prevent inserting raw <C-L> when using i_<C-O>. #17473
+  map('n', '<C-L>', '<Cmd>nohlsearch<Bar>diffupdate<Bar>normal! <C-L><CR>')
+  map('i', '<C-U>', '<C-G>u<C-U>')
+  map('i', '<C-W>', '<C-G>u<C-W>')
+  map('x', '*', 'y/\\V<C-R>"<CR>')
+  map('x', '#', 'y?\\V<C-R>"<CR>')
+  -- Use : instead of <Cmd> so that ranges are supported. #19365
+  map('n', '&', ':&&<CR>')
+
+  -- menus
+
+  -- TODO VimScript, no l10n
+  vim.cmd([[
+    aunmenu *
+    vnoremenu PopUp.Cut                     "+x
+    vnoremenu PopUp.Copy                    "+y
+    anoremenu PopUp.Paste                   "+gP
+    vnoremenu PopUp.Paste                   "+P
+    vnoremenu PopUp.Delete                  "_x
+    nnoremenu PopUp.Select\ All             ggVG
+    vnoremenu PopUp.Select\ All             gg0oG$
+    inoremenu PopUp.Select\ All             <C-Home><C-O>VG
+    anoremenu PopUp.-1-                     <Nop>
+    anoremenu PopUp.How-to\ disable\ mouse  <Cmd>help disable-mouse<CR>
+  ]])
+end
+
 require('vim._meta')
 
 return vim
diff --git a/src/nvim/main.c b/src/nvim/main.c
index db588d4694..b06b9630e2 100644
--- a/src/nvim/main.c
+++ b/src/nvim/main.c
@@ -356,7 +356,14 @@ int main(int argc, char **argv)
     abort();  // unreachable
   }
 
-  init_default_mappings();  // Default mappings.
+  // Default mappings (incl. menus)
+  Error err = ERROR_INIT;
+  Object o = nlua_exec(STATIC_CSTR_AS_STRING("return vim._init_default_mappings()"),
+                       (Array)ARRAY_DICT_INIT, &err);
+  assert(!ERROR_SET(&err));
+  api_clear_error(&err);
+  assert(o.type == kObjectTypeNil);
+  api_free_object(o);
   TIME_MSG("init default mappings");
 
   init_default_autocmds();
diff --git a/src/nvim/mapping.c b/src/nvim/mapping.c
index 7f4df66b4d..5a11ac686e 100644
--- a/src/nvim/mapping.c
+++ b/src/nvim/mapping.c
@@ -2113,24 +2113,6 @@ void f_mapcheck(typval_T *argvars, typval_T *rettv, FunPtr fptr)
   get_maparg(argvars, rettv, false);
 }
 
-void init_default_mappings(void)
-{
-  add_map("Y", "y$", MODE_NORMAL, false);
-
-  // Use normal! <C-L> to prevent inserting raw <C-L> when using i_<C-O>
-  // See https://github.com/neovim/neovim/issues/17473
-  add_map("<C-L>", "<Cmd>nohlsearch<Bar>diffupdate<Bar>normal! <C-L><CR>",
-          MODE_NORMAL, false);
-  add_map("<C-U>", "<C-G>u<C-U>", MODE_INSERT, false);
-  add_map("<C-W>", "<C-G>u<C-W>", MODE_INSERT, false);
-  add_map("*", "y/\\\\V<C-R>\"<CR>", MODE_VISUAL, false);
-  add_map("#", "y?\\\\V<C-R>\"<CR>", MODE_VISUAL, false);
-
-  // Use : instead of <Cmd> so that ranges are supported (e.g. 3& repeats the substitution on the
-  // next 3 lines)
-  add_map("&", ":&&<CR>", MODE_NORMAL, false);
-}
-
 /// Add a mapping. Unlike @ref do_map this copies the string arguments, so
 /// static or read-only strings can be used.
 ///
diff --git a/src/nvim/options.lua b/src/nvim/options.lua
index addc08d560..9e4a6a084c 100644
--- a/src/nvim/options.lua
+++ b/src/nvim/options.lua
@@ -1597,7 +1597,7 @@ return {
       short_desc=N_("the use of mouse clicks"),
       type='string', list='flags', scope={'global'},
       varname='p_mouse',
-      defaults={if_true=""}
+      defaults={if_true="nvi"}
     },
     {
       full_name='mousefocus', abbreviation='mousef',
@@ -1619,7 +1619,7 @@ return {
       short_desc=N_("changes meaning of mouse buttons"),
       type='string', scope={'global'},
       varname='p_mousem',
-      defaults={if_true="extend"}
+      defaults={if_true="popup_setpos"}
     },
     {
       full_name='mousescroll',
diff --git a/test/functional/core/startup_spec.lua b/test/functional/core/startup_spec.lua
index 31aa873aa6..51ab0e6382 100644
--- a/test/functional/core/startup_spec.lua
+++ b/test/functional/core/startup_spec.lua
@@ -524,8 +524,8 @@ describe('sysinit', function()
     screen:expect([[
       ^                                                            |
       Entering Debug mode.  Type "cont" to continue.              |
-      pre-vimrc command line                                      |
-      cmd: set noruler                                            |
+      nvim_exec()                                                 |
+      cmd: aunmenu *                                              |
       >                                                           |
       <" -u NONE -i NONE --cmd "set noruler" -D 1,1            All|
                                                                   |
diff --git a/test/functional/ex_cmds/menu_spec.lua b/test/functional/ex_cmds/menu_spec.lua
index 0cd32df27c..b9ed32c328 100644
--- a/test/functional/ex_cmds/menu_spec.lua
+++ b/test/functional/ex_cmds/menu_spec.lua
@@ -64,6 +64,8 @@ describe('menu_get', function()
   before_each(function()
     clear()
     command([=[
+      aunmenu *
+
       nnoremenu &Test.Test inormal<ESC>
       inoremenu Test.Test insert
       vnoremenu Test.Test x
@@ -396,6 +398,7 @@ describe('menu_get', function()
 
   before_each(function()
     clear()
+    command('aunmenu *')
   end)
 
   it('returns <keycode> representation of special keys', function()
diff --git a/test/functional/ui/mouse_spec.lua b/test/functional/ui/mouse_spec.lua
index e5284894cb..69b0d1ecec 100644
--- a/test/functional/ui/mouse_spec.lua
+++ b/test/functional/ui/mouse_spec.lua
@@ -32,7 +32,7 @@ describe('ui/mouse/input', function()
       [6] = {foreground = Screen.colors.Grey100, background = Screen.colors.Red},
       [7] = {bold = true, foreground = Screen.colors.SeaGreen4},
     })
-    command("set display-=msgsep")
+    command("set display-=msgsep mousemodel=extend")
     feed('itesting<cr>mouse<cr>support and selection<esc>')
     screen:expect([[
       testing                  |
diff --git a/test/functional/ui/options_spec.lua b/test/functional/ui/options_spec.lua
index 346a64c63b..c2b0bcdb64 100644
--- a/test/functional/ui/options_spec.lua
+++ b/test/functional/ui/options_spec.lua
@@ -63,17 +63,18 @@ describe('UI receives option updates', function()
     end
     screen:attach()
     screen:expect(function()
-      eq({'mouse_off'}, evs)
+      eq({'mouse_on'}, evs)
     end)
-    command("set mouse=nvi")
+    command("set mouse=")
+    command("set mouse&")
     screen:expect(function()
-      eq({'mouse_off','mouse_on'}, evs)
+      eq({'mouse_on','mouse_off', 'mouse_on'}, evs)
     end)
     screen:detach()
-    eq({'mouse_off','mouse_on'}, evs)
+    eq({'mouse_on','mouse_off', 'mouse_on'}, evs)
     screen:attach()
     screen:expect(function()
-      eq({'mouse_off','mouse_on','mouse_on'}, evs)
+      eq({'mouse_on','mouse_off','mouse_on', 'mouse_on'}, evs)
     end)
   end)
 
diff --git a/test/functional/ui/popupmenu_spec.lua b/test/functional/ui/popupmenu_spec.lua
index 0cd991756c..7b0005bcf1 100644
--- a/test/functional/ui/popupmenu_spec.lua
+++ b/test/functional/ui/popupmenu_spec.lua
@@ -2367,6 +2367,7 @@ describe('builtin popupmenu', function()
       call setline(1, 'popup menu test')
       set mouse=a mousemodel=popup
 
+      aunmenu PopUp
       menu PopUp.foo :let g:menustr = 'foo'<CR>
       menu PopUp.bar :let g:menustr = 'bar'<CR>
       menu PopUp.baz :let g:menustr = 'baz'<CR>
@@ -2554,6 +2555,7 @@ describe('builtin popupmenu with ui/ext_multigrid', function()
       call setline(1, 'popup menu test')
       set mouse=a mousemodel=popup
 
+      aunmenu PopUp
       menu PopUp.foo :let g:menustr = 'foo'<CR>
       menu PopUp.bar :let g:menustr = 'bar'<CR>
       menu PopUp.baz :let g:menustr = 'baz'<CR>
diff --git a/test/functional/ui/statusline_spec.lua b/test/functional/ui/statusline_spec.lua
index 82e669856f..1e1066d48a 100644
--- a/test/functional/ui/statusline_spec.lua
+++ b/test/functional/ui/statusline_spec.lua
@@ -17,7 +17,7 @@ describe('statusline clicks', function()
     clear()
     screen = Screen.new(40, 8)
     screen:attach()
-    command('set laststatus=2')
+    command('set laststatus=2 mousemodel=extend')
     exec([=[
       function! MyClickFunc(minwid, clicks, button, mods)
         let mods = trim(a:mods)