feat(treesitter): allow get_node to return anonymous nodes

Adds a new field `include_anonymous` to the `get_node` options to allow
anonymous nodes to be returned.

runtime/doc/news.txt

@@ -167,6 +167,8 @@ TERMINAL
 TREESITTER
 
 • |LanguageTree:node_for_range()| gets anonymous and named nodes for a range
+• |vim.treesitter.get_node()| now takes an option `include_anonymous`, default
+  false, which allows it to return anonymous nodes as well as named nodes.
 
 TUI
 

runtime/doc/treesitter.txt

@@ -773,6 +773,8 @@ get_node({opts})                                   *vim.treesitter.get_node()*
                   filetype)
                 • {ignore_injections} (`boolean?`) Ignore injected languages
                   (default true)
+                • {include_anonymous} (`boolean?`) Include anonymous nodes
+                  (default false)
 
     Return: ~
         (`TSNode?`) Node at the given position

runtime/lua/vim/treesitter.lua

@@ -342,6 +342,9 @@ end
 ---
 --- Ignore injected languages (default true)
 --- @field ignore_injections boolean?
+---
+--- Include anonymous nodes (default false)
+--- @field include_anonymous boolean?
 
 --- Returns the smallest named node at the given position
 ---
@@ -388,6 +391,9 @@ function M.get_node(opts)
     return
   end
 
+  if opts.include_anonymous then
+    return root_lang_tree:node_for_range(ts_range, opts)
+  end
   return root_lang_tree:named_node_for_range(ts_range, opts)
 end
 

test/functional/treesitter/node_spec.lua

@@ -55,6 +55,23 @@ describe('treesitter node API', function()
     eq('identifier', lua_eval('node:type()'))
   end)
 
+  it('get_node() with anonymous nodes included', function()
+    insert([[print('test')]])
+
+    exec_lua([[
+      parser = vim.treesitter.get_parser(0, 'lua')
+      tree = parser:parse()[1]
+      node = vim.treesitter.get_node({
+        bufnr = 0,
+        pos = { 0, 6 }, -- on the first apostrophe
+        include_anonymous = true,
+      })
+    ]])
+
+    eq("'", lua_eval('node:type()'))
+    eq(false, lua_eval('node:named()'))
+  end)
+
   it('can move between siblings', function()
     insert([[
       int main(int x, int y, int z) {