use positive option "allow_duplicates" instead of negative "dedupe"

doc/nvim-treesitter.txt

@@ -447,7 +447,7 @@ Default options (lua syntax):
     type_patterns = {'class', 'function', 'method'},
     transform_fn = function(line, _node) return line:gsub('%s*[%[%(%{]*%s*$', '') end,
     separator = ' -> ',
-    dedupe = true
+    allow_duplicates = false
   }
 <
 - `indicator_size` - How long should the string be. If longer, it is cut from
@@ -457,7 +457,7 @@ Default options (lua syntax):
   default removes opening brackets and spaces from end. Takes two arguments:
   the text of the line in question, and the corresponding treesitter node.
 - `separator` - Separator between nodes.
-- `dedupe` - Whether or not to remove duplicate components.
+- `allow_duplicates` - Whether or not to remove duplicate components.
 
 						  *nvim_treesitter#foldexpr()*
 nvim_treesitter#foldexpr()~

lua/nvim-treesitter/statusline.lua

@@ -21,10 +21,7 @@ function M.statusline(opts)
   local type_patterns = options.type_patterns or { "class", "function", "method" }
   local transform_fn = options.transform_fn or transform_line
   local separator = options.separator or " -> "
-  local dedupe = options.dedupe
-  if dedupe == nil then
-    dedupe = true
-  end
+  local allow_duplicates = options.allow_duplicates or false
 
   local current_node = ts_utils.get_node_at_cursor()
   if not current_node then
@@ -37,7 +34,7 @@ function M.statusline(opts)
   while expr do
     local line = ts_utils._get_line_for_node(expr, type_patterns, transform_fn, bufnr)
     if line ~= "" then
-      if not dedupe or not vim.tbl_contains(lines, line) then
+      if allow_duplicates or not vim.tbl_contains(lines, line) then
         table.insert(lines, 1, line)
       end
     end