feat: support accepting and drawing by index

Closes #382

lua/blink/cmp/completion/list.lua

@@ -21,7 +21,10 @@
 ---
 --- @field undo_preview fun()
 --- @field apply_preview fun(item: blink.cmp.CompletionItem)
---- @field accept fun(): boolean Applies the currently selected item, returning true if it succeeded
+--- @field accept fun(opts?: blink.cmp.CompletionListAcceptOpts): boolean Applies the currently selected item, returning true if it succeeded
+
+--- @class blink.cmp.CompletionListAcceptOpts
+--- @field index? number The index of the item to accept, if not provided, the currently selected item will be accepted
 
 --- @class blink.cmp.CompletionListShowEvent
 --- @field items blink.cmp.CompletionItem[]
@@ -164,8 +167,9 @@ end
 
 ---------- Accept ----------
 
-function list.accept()
-  local item = list.get_selected_item()
+function list.accept(opts)
+  opts = opts or {}
+  local item = list.items[opts.index or list.selected_item_idx]
   if item == nil then return false end
 
   list.undo_preview()

lua/blink/cmp/completion/windows/render/context.lua

@@ -1,6 +1,7 @@
 --- @class blink.cmp.DrawItemContext
 --- @field self blink.cmp.Draw
 --- @field item blink.cmp.CompletionItem
+--- @field idx number
 --- @field label string
 --- @field label_detail string
 --- @field label_description string
@@ -24,16 +25,17 @@ function context.get_from_items(draw, items)
 
   local ctxs = {}
   for idx, item in ipairs(items) do
-    ctxs[idx] = context.new(draw, item, matched_indices[idx])
+    ctxs[idx] = context.new(draw, idx, item, matched_indices[idx])
   end
   return ctxs
 end
 
 --- @param draw blink.cmp.Draw
+--- @param item_idx number
 --- @param item blink.cmp.CompletionItem
 --- @param matched_indices number[]
 --- @return blink.cmp.DrawItemContext
-function context.new(draw, item, matched_indices)
+function context.new(draw, item_idx, item, matched_indices)
   local config = require('blink.cmp.config').appearance
   local kind = require('blink.cmp.types').CompletionItemKind[item.kind] or 'Unknown'
   local kind_icon = config.kind_icons[kind] or config.kind_icons.Field
@@ -54,6 +56,7 @@ function context.new(draw, item, matched_indices)
   return {
     self = draw,
     item = item,
+    idx = item_idx,
     label = label,
     label_detail = label_detail,
     label_description = label_description,

lua/blink/cmp/init.lua

@@ -41,14 +41,15 @@ function cmp.cancel()
   return true
 end
 
-function cmp.accept()
+--- @param opts? blink.cmp.CompletionListAcceptOpts
+function cmp.accept(opts)
   if not require('blink.cmp.completion.windows.menu').win:is_open() then return end
 
   local completion_list = require('blink.cmp.completion.list')
   local item = completion_list.get_selected_item()
   if item == nil then return end
 
-  vim.schedule(function() completion_list.accept() end)
+  vim.schedule(function() completion_list.accept(opts) end)
   return true
 end