treesitter context

treesitter_context.lua

vim.keymap.set("n", "<C-g>", function()
  local hl_keywords = {
    ["class"] = true,
    ["function"] = true,
    ["namespace"] = true,
    ["method"] = true,
    ["type"] = true,
    ["enum"] = true,
    ["field"] = true,
  }

  local node = vim.treesitter.get_node()
  local sep_list = {
    cpp = "::",
    c = "::",
  }
  local tbl = {}

  while node do
    local t = node:type()

    -- declarator|definition|specifier: void print(const char*) { ... }
    if t:find("declaration$") or t:find("definition$") or t:find("specifier$") then
      local word = t:match("(%w+)_")
      local hl_type = hl_keywords[word] and word or "Conceal"

      --  signature: print(const char*)
      for signature_node in node:iter_children() do
        local signature_type = signature_node:type()
        if
          (signature_type:find("declarator$") or signature_type:find("identifier$"))
          and signature_type ~= "qualified_identifier"
        then
          hl_type = hl_keywords[hl_type] and hl_type or signature_type:match("(%w+)_")

          -- name: print
          for name_node in signature_node:iter_children() do
            local name_type = name_node:type()
            if name_type:find("identifier$") or name_type == "destructor_name" then
              hl_type = hl_keywords[hl_type] and hl_type or name_type:match("(%w+)_")
              if hl_keywords[hl_type] then
                table.insert(tbl, 1, "%#@lsp.type." .. hl_type .. "#" .. vim.treesitter.get_node_text(name_node, 0))
                hl_type = "Conceal"
              end
            end
          end

          if hl_keywords[hl_type] then
            table.insert(tbl, 1, "%#@lsp.type." .. hl_type .. "#" .. vim.treesitter.get_node_text(signature_node, 0))
            hl_type = "Conceal"
          end
        end
      end
    end

    node = node:parent()
  end
  if not vim.tbl_isempty(tbl) then
    vim.o.statusline = " %=%##(" .. table.concat(tbl, "%#Conceal#" .. (sep_list[vim.o.ft] or "->")) .. "%##)%= "
  end
end, { desc = "Show Treesitter Context" })