fix(mouse): correct dragged position in composed layout

3 files changed, 196 insertions, 1 deletions

diff --git a/src/nvim/mouse.c b/src/nvim/mouse.c
index cf463fd40a..cd9f5fc83e 100644
--- a/src/nvim/mouse.c
+++ b/src/nvim/mouse.c
@@ -236,6 +236,11 @@ retnomove:
       redraw_curbuf_later(INVERTED);            // delete the inversion
     }
 
+    if (grid == 0) {
+      row -= curwin->w_grid_alloc.comp_row+curwin->w_grid.row_offset;
+      col -= curwin->w_grid_alloc.comp_col+curwin->w_grid.col_offset;
+    }
+
     // When clicking beyond the end of the window, scroll the screen.
     // Scroll by however many rows outside the window we are.
     if (row < 0) {
@@ -476,7 +481,7 @@ win_T *mouse_find_win(int *gridp, int *rowp, int *colp)
 static win_T *mouse_find_grid_win(int *gridp, int *rowp, int *colp)
 {
   if (*gridp == msg_grid.handle) {
-    // rowp += msg_grid_pos;  // PVS: dead store #11612
+    *rowp += msg_grid_pos;
     *gridp = DEFAULT_GRID_HANDLE;
   } else if (*gridp > 1) {
     win_T *wp = get_win_by_grid_handle(*gridp);
diff --git a/test/functional/ui/float_spec.lua b/test/functional/ui/float_spec.lua
index e57c63bb0f..6c2c4b398a 100644
--- a/test/functional/ui/float_spec.lua
+++ b/test/functional/ui/float_spec.lua
@@ -46,6 +46,7 @@ describe('float window', function()
     [24] = {foreground = Screen.colors.Black, background = Screen.colors.Grey80};
     [25] = {blend = 100, background = Screen.colors.Gray0};
     [26] = {blend = 80, background = Screen.colors.Gray0};
+    [27] = {background = Screen.colors.LightGray};
   }
 
   it('behavior', function()
@@ -6174,6 +6175,132 @@ describe('float window', function()
       end)
     end)
 
+    it("left drag changes visual selection in float window", function()
+      local buf = meths.create_buf(false,false)
+      meths.buf_set_lines(buf, 0, -1, true, {'foo', 'bar'})
+      meths.open_win(buf, false, {relative='editor', width=20, height=3, row=2, col=5})
+      if multigrid then
+        screen:expect{grid=[[
+        ## grid 1
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [3:----------------------------------------]|
+        ## grid 2
+          ^                                        |
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+        ## grid 3
+                                                  |
+        ## grid 5
+          {1:foo                 }|
+          {1:bar                 }|
+          {2:~                   }|
+        ]], float_pos={
+          [5] = {{id = 1002}, "NW", 1, 2, 5, true, 50};
+        }, win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 2, curline = 0, curcol = 0, linecount = 1};
+          [5] = {win = {id = 1002}, topline = 0, botline = 3, curline = 0, curcol = 0, linecount = 2};
+        }}
+        meths.input_mouse('left', 'press', '', 5, 0, 0)
+        screen:expect{grid=[[
+        ## grid 1
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [3:----------------------------------------]|
+        ## grid 2
+                                                  |
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+        ## grid 3
+                                                  |
+        ## grid 5
+          {1:^foo                 }|
+          {1:bar                 }|
+          {2:~                   }|
+        ]], float_pos={
+          [5] = {{id = 1002}, "NW", 1, 2, 5, true, 50};
+        }, win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 2, curline = 0, curcol = 0, linecount = 1};
+          [5] = {win = {id = 1002}, topline = 0, botline = 3, curline = 0, curcol = 0, linecount = 2};
+        }}
+        meths.input_mouse('left', 'drag', '', 5, 1, 2)
+        screen:expect{grid=[[
+        ## grid 1
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [2:----------------------------------------]|
+          [3:----------------------------------------]|
+        ## grid 2
+                                                  |
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+          {0:~                                       }|
+        ## grid 3
+          {3:-- VISUAL --}                            |
+        ## grid 5
+          {27:foo}{1:                 }|
+          {27:ba}{1:^r                 }|
+          {2:~                   }|
+        ]], float_pos={
+          [5] = {{id = 1002}, "NW", 1, 2, 5, true, 50};
+        }, win_viewport={
+          [2] = {win = {id = 1000}, topline = 0, botline = 2, curline = 0, curcol = 0, linecount = 1};
+          [5] = {win = {id = 1002}, topline = 0, botline = 3, curline = 1, curcol = 2, linecount = 2};
+        }}
+      else
+        screen:expect{grid=[[
+          ^                                        |
+          {0:~                                       }|
+          {0:~    }{1:foo                 }{0:               }|
+          {0:~    }{1:bar                 }{0:               }|
+          {0:~    }{2:~                   }{0:               }|
+          {0:~                                       }|
+                                                  |
+        ]]}
+
+        meths.input_mouse('left', 'press', '', 0, 2, 5)
+        screen:expect{grid=[[
+                                                  |
+          {0:~                                       }|
+          {0:~    }{1:^foo                 }{0:               }|
+          {0:~    }{1:bar                 }{0:               }|
+          {0:~    }{2:~                   }{0:               }|
+          {0:~                                       }|
+                                                  |
+        ]]}
+
+        meths.input_mouse('left', 'drag', '', 0, 3, 7)
+        screen:expect{grid=[[
+                                                  |
+          {0:~                                       }|
+          {0:~    }{27:foo}{1:                 }{0:               }|
+          {0:~    }{27:ba}{1:^r                 }{0:               }|
+          {0:~    }{2:~                   }{0:               }|
+          {0:~                                       }|
+          {3:-- VISUAL --}                            |
+        ]]}
+      end
+    end)
+
     it("'winblend' option", function()
       screen:try_resize(50,9)
       screen:set_default_attr_ids({
diff --git a/test/functional/ui/mouse_spec.lua b/test/functional/ui/mouse_spec.lua
index d3fe38ef52..baacef358f 100644
--- a/test/functional/ui/mouse_spec.lua
+++ b/test/functional/ui/mouse_spec.lua
@@ -585,6 +585,69 @@ describe('ui/mouse/input', function()
     ]])
   end)
 
+  it('left drag changes visual selection in split layout', function()
+    screen:try_resize(53,14)
+    command('set mouse=a')
+    command('vsplit')
+    command('wincmd l')
+    command('below split')
+    command('enew')
+    feed('ifoo\nbar<esc>')
+
+    screen:expect{grid=[[
+      testing                   {4:│}testing                   |
+      mouse                     {4:│}mouse                     |
+      support and selection     {4:│}support and selection     |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│[No Name] [+]             }|
+      {0:~                         }{4:│}foo{0:$}                      |
+      {0:~                         }{4:│}ba^r{0:$}                      |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {4:[No Name] [+]              }{5:[No Name] [+]             }|
+                                                           |
+    ]]}
+
+    meths.input_mouse('left', 'press', '', 0, 6, 27)
+    screen:expect{grid=[[
+      testing                   {4:│}testing                   |
+      mouse                     {4:│}mouse                     |
+      support and selection     {4:│}support and selection     |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│[No Name] [+]             }|
+      {0:~                         }{4:│}^foo{0:$}                      |
+      {0:~                         }{4:│}bar{0:$}                      |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {4:[No Name] [+]              }{5:[No Name] [+]             }|
+                                                           |
+    ]]}
+    meths.input_mouse('left', 'drag', '', 0, 7, 30)
+
+    screen:expect{grid=[[
+      testing                   {4:│}testing                   |
+      mouse                     {4:│}mouse                     |
+      support and selection     {4:│}support and selection     |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│[No Name] [+]             }|
+      {0:~                         }{4:│}{1:foo}{3:$}                      |
+      {0:~                         }{4:│}{1:bar}{0:^$}                      |
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {0:~                         }{4:│}{0:~                         }|
+      {4:[No Name] [+]              }{5:[No Name] [+]             }|
+      {2:-- VISUAL --}                                         |
+    ]]}
+  end)
+
   it('two clicks will select the word and enter VISUAL', function()
     feed('<LeftMouse><2,2><LeftMouse><2,2>')
     screen:expect([[