feat(api): add "move" to nvim_input_mouse

runtime/doc/api.txt

@@ -1067,9 +1067,11 @@ nvim_input_mouse({button}, {action}, {modifier}, {grid}, {row}, {col})
         |api-fast|
 
     Parameters: ~
-        {button}    Mouse button: one of "left", "right", "middle", "wheel".
+        {button}    Mouse button: one of "left", "right", "middle", "wheel",
+                    "move".
         {action}    For ordinary buttons, one of "press", "drag", "release".
                     For the wheel, one of "up", "down", "left", "right".
+                    Ignored for "move".
         {modifier}  String of modifiers each represented by a single char. The
                     same specifiers are used as for a key press, except that
                     the "-" separator is optional, so "C-A-", "c-a" and "CA"

src/nvim/api/vim.c

@@ -336,9 +336,9 @@ Integer nvim_input(String keys)
 ///       mouse input in a GUI. The deprecated pseudokey form
 ///       ("<LeftMouse><col,row>") of |nvim_input()| has the same limitation.
 ///
-/// @param button Mouse button: one of "left", "right", "middle", "wheel".
+/// @param button Mouse button: one of "left", "right", "middle", "wheel", "move".
 /// @param action For ordinary buttons, one of "press", "drag", "release".
-///               For the wheel, one of "up", "down", "left", "right".
+///               For the wheel, one of "up", "down", "left", "right". Ignored for "move".
 /// @param modifier String of modifiers each represented by a single char.
 ///                 The same specifiers are used as for a key press, except
 ///                 that the "-" separator is optional, so "C-A-", "c-a"
@@ -365,6 +365,8 @@ void nvim_input_mouse(String button, String action, String modifier, Integer gri
     code = KE_RIGHTMOUSE;
   } else if (strequal(button.data, "wheel")) {
     code = KE_MOUSEDOWN;
+  } else if (strequal(button.data, "move")) {
+    code = KE_MOUSEMOVE;
   } else {
     goto error;
   }
@@ -381,7 +383,7 @@ void nvim_input_mouse(String button, String action, String modifier, Integer gri
     } else {
       goto error;
     }
-  } else {
+  } else if (code != KE_MOUSEMOVE) {
     if (strequal(action.data, "press")) {
       // pass
     } else if (strequal(action.data, "drag")) {

test/functional/ui/mouse_spec.lua

@@ -1585,7 +1585,20 @@ describe('ui/mouse/input', function()
     eq(0, meths.get_var('mouse_up2'))
   end)
 
-  it('feeding <MouseMove> does not use uninitialized memory #19480', function()
+  it('<MouseMove> is not translated into multiclicks and can be mapped', function()
+    meths.set_var('mouse_move', 0)
+    meths.set_var('mouse_move2', 0)
+    command('nnoremap <MouseMove> <Cmd>let g:mouse_move += 1<CR>')
+    command('nnoremap <2-MouseMove> <Cmd>let g:mouse_move2 += 1<CR>')
+    feed('<MouseMove><0,0>')
+    feed('<MouseMove><0,0>')
+    meths.input_mouse('move', '', '', 0, 0, 0)
+    meths.input_mouse('move', '', '', 0, 0, 0)
+    eq(4, meths.get_var('mouse_move'))
+    eq(0, meths.get_var('mouse_move2'))
+  end)
+
+  it('feeding <MouseMove> in Normal mode does not use uninitialized memory #19480', function()
     feed('<MouseMove>')
     helpers.poke_eventloop()
     helpers.assert_alive()

test/functional/ui/popupmenu_spec.lua

@@ -3075,5 +3075,68 @@ describe('builtin popupmenu with ui/ext_multigrid', function()
       :let g:menustr = 'foo'          |
     ]]})
     eq('foo', meths.get_var('menustr'))
+    meths.input_mouse('right', 'press', '', 2, 0, 4)
+    screen:expect({grid=[[
+    ## grid 1
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [3:--------------------------------]|
+    ## grid 2
+      ^popup menu test                 |
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+    ## grid 3
+      :let g:menustr = 'foo'          |
+    ## grid 4
+      {n: foo }|
+      {n: bar }|
+      {n: baz }|
+    ]], float_pos={[4] = {{id = -1}, 'NW', 2, 1, 3, false, 100}}})
+    meths.input_mouse('move', '', '', 2, 3, 6)
+    screen:expect({grid=[[
+    ## grid 1
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [3:--------------------------------]|
+    ## grid 2
+      ^popup menu test                 |
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+    ## grid 3
+      :let g:menustr = 'foo'          |
+    ## grid 4
+      {n: foo }|
+      {n: bar }|
+      {s: baz }|
+    ]], float_pos={[4] = {{id = -1}, 'NW', 2, 1, 3, false, 100}}})
+    meths.input_mouse('left', 'press', '', 2, 2, 6)
+    screen:expect({grid=[[
+    ## grid 1
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [2:--------------------------------]|
+      [3:--------------------------------]|
+    ## grid 2
+      ^popup menu test                 |
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+      {1:~                               }|
+    ## grid 3
+      :let g:menustr = 'bar'          |
+    ]]})
+    eq('bar', meths.get_var('menustr'))
   end)
 end)