add function to check if in comment (#676)

* feat(utils): added function to check if in comment

* moved functions into config.context and generalized

* feat(configs.context): added annotations

lua/cmp/config/context.lua

@@ -0,0 +1,69 @@
+local context = {}
+
+---Check if cursor is in syntax group
+---@param group string
+---@return boolean
+context.in_syntax_group = function(group)
+  local lnum, col = vim.fn.line('.'), math.min(vim.fn.col('.'), #vim.fn.getline('.'))
+  for _, syn_id in ipairs(vim.fn.synstack(lnum, col)) do
+    syn_id = vim.fn.synIDtrans(syn_id) -- Resolve :highlight links
+    if vim.fn.synIDattr(syn_id, 'name') == group then
+      return true
+    end
+  end
+end
+
+---Check if cursor is in treesitter capture
+---@param capture string
+---@return boolean
+context.in_treesitter_capture = function(capture)
+  local highlighter = require('vim.treesitter.highlighter')
+  local ts_utils = require('nvim-treesitter.ts_utils')
+  local buf = vim.api.nvim_get_current_buf()
+  local row, col = unpack(vim.api.nvim_win_get_cursor(0))
+  row = row - 1
+  if vim.api.nvim_get_mode().mode == 'i' then
+    col = col - 1
+  end
+
+  local self = highlighter.active[buf]
+  if not self then
+    return {}
+  end
+
+  local node_types = {}
+
+  self.tree:for_each_tree(function(tstree, tree)
+    if not tstree then
+      return
+    end
+
+    local root = tstree:root()
+    local root_start_row, _, root_end_row, _ = root:range()
+
+    if root_start_row > row or root_end_row < row then
+      return
+    end
+
+    local query = self:get_query(tree:lang())
+
+    if not query:query() then
+      return
+    end
+
+    local iter = query:query():iter_captures(root, self.bufnr, row, row + 1)
+
+    for _, node, _ in iter do
+      if ts_utils.is_in_node_range(node, row, col) then
+        table.insert(node_types, node:type())
+      end
+    end
+  end, true)
+  if vim.tbl_contains(node_types, capture) then
+    return true
+  else
+    return false
+  end
+end
+
+return context