feat: adds M mapping in normal mode (#544)

lua/telescope/actions/init.lua

@@ -78,6 +78,11 @@ function actions.move_to_top(prompt_bufnr)
   ))
 end
 
+function actions.move_to_middle(prompt_bufnr)
+  local current_picker = actions.get_current_picker(prompt_bufnr)
+  current_picker:set_selection(p_scroller.middle(nil, current_picker.max_results, nil))
+end
+
 function actions.move_to_bottom(prompt_bufnr)
   local current_picker = actions.get_current_picker(prompt_bufnr)
   current_picker:set_selection(p_scroller.bottom(current_picker.sorting_strategy,

lua/telescope/mappings.lua

@@ -39,6 +39,7 @@ mappings.default_mappings = config.values.default_mappings or {
       ["j"] = actions.move_selection_next,
       ["k"] = actions.move_selection_previous,
       ["H"] = actions.move_to_top,
+      ["M"] = actions.move_to_middle,
       ["L"] = actions.move_to_bottom,
 
       ["<Down>"] = actions.move_selection_next,

lua/telescope/pickers/scroller.lua

@@ -80,6 +80,10 @@ scroller.top = function(sorting_strategy, max_results, num_results)
   return (num_results > max_results) and 0 or (max_results - num_results)
 end
 
+scroller.middle = function(sorting_strategy, max_results, num_results)
+  return math.floor(max_results/2)
+end
+
 scroller.bottom = function(sorting_strategy, max_results, num_results)
   if sorting_strategy == 'ascending' then
     return math.min(max_results, num_results) - 1

lua/tests/automated/scroller_spec.lua

@@ -112,7 +112,14 @@ describe('scroller', function()
     end)
   end)
 
-  describe('should give top and bottom index', function()
+
+  describe('should give top, middle and bottom index', function()
+    it('should handle middle index', function()
+      eq(5, p_scroller.middle(nil, 11, nil))
+      eq(10, p_scroller.middle(nil, 20, nil))
+      eq(12, p_scroller.middle(nil, 25, nil))
+    end)
+
     it('should handle ascending', function()
       eq(0, p_scroller.top('ascending', 20, 1000))
       eq(19, p_scroller.bottom('ascending', 20, 1000))