feat(keysets): teach Union and LuaRefOf

11 files changed, 258 insertions, 109 deletions

diff --git a/runtime/lua/vim/_meta/api.lua b/runtime/lua/vim/_meta/api.lua
index 3c9b9d4f44..acd12b353d 100644
--- a/runtime/lua/vim/_meta/api.lua
+++ b/runtime/lua/vim/_meta/api.lua
@@ -1012,7 +1012,7 @@ function vim.api.nvim_create_namespace(name) end
 --- ```
 ---
 --- @param name string Name of the new user command. Must begin with an uppercase letter.
---- @param command any Replacement command to execute when this user command is executed. When called
+--- @param command string|fun(args: vim.api.keyset.create_user_command.command_args) Replacement command to execute when this user command is executed. When called
 --- from Lua, the command can also be a Lua function. The function is called with a
 --- single table argument that contains the following keys:
 --- - name: (string) Command name
diff --git a/runtime/lua/vim/_meta/api_keysets.lua b/runtime/lua/vim/_meta/api_keysets.lua
index bf184dee2d..e11dddb2d3 100644
--- a/runtime/lua/vim/_meta/api_keysets.lua
+++ b/runtime/lua/vim/_meta/api_keysets.lua
@@ -4,11 +4,11 @@
 error('Cannot require a meta file')
 
 --- @class vim.api.keyset.buf_attach
---- @field on_lines? function
---- @field on_bytes? function
---- @field on_changedtick? function
---- @field on_detach? function
---- @field on_reload? function
+--- @field on_lines? fun(_: "lines", bufnr: integer, changedtick: integer, first: integer, last_old: integer, last_new: integer, byte_count: integer, deleted_codepoints?: integer, deleted_codeunits?: integer): boolean?
+--- @field on_bytes? fun(_: "bytes", bufnr: integer, changedtick: integer, start_row: integer, start_col: integer, start_byte: integer, old_end_row: integer, old_end_col: integer, old_end_byte: integer, new_end_row: integer, new_end_col: integer, new_end_byte: integer): boolean?
+--- @field on_changedtick? fun(_: "changedtick", bufnr: integer, changedtick: integer)
+--- @field on_detach? fun(_: "detach", bufnr: integer)
+--- @field on_reload? fun(_: "reload", bufnr: integer)
 --- @field utf_sizes? boolean
 --- @field preview? boolean
 
@@ -18,9 +18,9 @@ error('Cannot require a meta file')
 
 --- @class vim.api.keyset.clear_autocmds
 --- @field buffer? integer
---- @field event? any
---- @field group? any
---- @field pattern? any
+--- @field event? string|string[]
+--- @field group? integer|string
+--- @field pattern? string|string[]
 
 --- @class vim.api.keyset.cmd
 --- @field cmd? string
@@ -28,12 +28,12 @@ error('Cannot require a meta file')
 --- @field count? integer
 --- @field reg? string
 --- @field bang? boolean
---- @field args? any[]
+--- @field args? string[]
 --- @field magic? table<string,any>
 --- @field mods? table<string,any>
---- @field nargs? any
---- @field addr? any
---- @field nextcmd? any
+--- @field nargs? integer|string
+--- @field addr? string
+--- @field nextcmd? string
 
 --- @class vim.api.keyset.cmd_magic
 --- @field file? boolean
@@ -72,20 +72,20 @@ error('Cannot require a meta file')
 --- @field info? string
 
 --- @class vim.api.keyset.context
---- @field types? any[]
+--- @field types? string[]
 
 --- @class vim.api.keyset.create_augroup
---- @field clear? any
+--- @field clear? boolean
 
 --- @class vim.api.keyset.create_autocmd
 --- @field buffer? integer
---- @field callback? any
+--- @field callback? string|(fun(args: vim.api.keyset.create_autocmd.callback_args): boolean?)
 --- @field command? string
 --- @field desc? string
---- @field group? any
+--- @field group? integer|string
 --- @field nested? boolean
 --- @field once? boolean
---- @field pattern? any
+--- @field pattern? string|string[]
 
 --- @class vim.api.keyset.echo_opts
 --- @field verbose? boolean
@@ -103,19 +103,19 @@ error('Cannot require a meta file')
 
 --- @class vim.api.keyset.exec_autocmds
 --- @field buffer? integer
---- @field group? any
+--- @field group? integer|string
 --- @field modeline? boolean
---- @field pattern? any
+--- @field pattern? string|string[]
 --- @field data? any
 
 --- @class vim.api.keyset.exec_opts
 --- @field output? boolean
 
 --- @class vim.api.keyset.get_autocmds
---- @field event? any
---- @field group? any
---- @field pattern? any
---- @field buffer? any
+--- @field event? string|string[]
+--- @field group? integer|string
+--- @field pattern? string|string[]
+--- @field buffer? integer|integer[]
 
 --- @class vim.api.keyset.get_commands
 --- @field builtin? boolean
@@ -154,17 +154,17 @@ error('Cannot require a meta file')
 --- @field altfont? boolean
 --- @field nocombine? boolean
 --- @field default? boolean
---- @field cterm? any
---- @field foreground? any
---- @field fg? any
---- @field background? any
---- @field bg? any
---- @field ctermfg? any
---- @field ctermbg? any
---- @field special? any
---- @field sp? any
---- @field link? any
---- @field global_link? any
+--- @field cterm? integer|string
+--- @field foreground? integer|string
+--- @field fg? integer|string
+--- @field background? integer|string
+--- @field bg? integer|string
+--- @field ctermfg? integer|string
+--- @field ctermbg? integer|string
+--- @field special? integer|string
+--- @field sp? integer|string
+--- @field link? integer|string
+--- @field global_link? integer|string
 --- @field fallback? boolean
 --- @field blend? integer
 --- @field fg_indexed? boolean
@@ -201,7 +201,7 @@ error('Cannot require a meta file')
 --- @field wins? any[]
 
 --- @class vim.api.keyset.open_term
---- @field on_input? function
+--- @field on_input? fun(_: "input", term: integer, bufnr: integer, data: any)
 --- @field force_crlf? boolean
 
 --- @class vim.api.keyset.option
@@ -227,20 +227,20 @@ error('Cannot require a meta file')
 --- @field do_source? boolean
 
 --- @class vim.api.keyset.set_decoration_provider
---- @field on_start? function
---- @field on_buf? function
---- @field on_win? function
---- @field on_line? function
---- @field on_end? function
---- @field _on_hl_def? function
---- @field _on_spell_nav? function
+--- @field on_start? fun(_: "start", tick: integer)
+--- @field on_buf? fun(_: "buf", bufnr: integer, tick: integer)
+--- @field on_win? fun(_: "win", winid: integer, bufnr: integer, toprow: integer, botrow: integer)
+--- @field on_line? fun(_: "line", winid: integer, bufnr: integer, row: integer)
+--- @field on_end? fun(_: "end", tick: integer)
+--- @field _on_hl_def? fun(_: "hl_def")
+--- @field _on_spell_nav? fun(_: "spell_nav")
 
 --- @class vim.api.keyset.set_extmark
 --- @field id? integer
 --- @field end_line? integer
 --- @field end_row? integer
 --- @field end_col? integer
---- @field hl_group? number|string
+--- @field hl_group? integer|string
 --- @field virt_text? any[]
 --- @field virt_text_pos? string
 --- @field virt_text_win_col? integer
@@ -258,10 +258,10 @@ error('Cannot require a meta file')
 --- @field virt_lines_leftcol? boolean
 --- @field strict? boolean
 --- @field sign_text? string
---- @field sign_hl_group? number|string
---- @field number_hl_group? number|string
---- @field line_hl_group? number|string
---- @field cursorline_hl_group? number|string
+--- @field sign_hl_group? integer|string
+--- @field number_hl_group? integer|string
+--- @field line_hl_group? integer|string
+--- @field cursorline_hl_group? integer|string
 --- @field conceal? string
 --- @field spell? boolean
 --- @field ui_watched? boolean
@@ -292,7 +292,7 @@ error('Cannot require a meta file')
 --- @field relative? string
 --- @field split? string
 --- @field win? integer
---- @field bufpos? any[]
+--- @field bufpos? integer[]
 --- @field external? boolean
 --- @field focusable? boolean
 --- @field mouse? boolean
@@ -315,12 +315,12 @@ error('Cannot require a meta file')
 --- @field end_vcol? integer
 
 --- @class vim.api.keyset.xdl_diff
---- @field on_hunk? function
+--- @field on_hunk? fun(start_a: integer, count_a: integer, start_b: integer, count_b: integer): integer?
 --- @field result_type? string
 --- @field algorithm? string
 --- @field ctxlen? integer
 --- @field interhunkctxlen? integer
---- @field linematch? any
+--- @field linematch? boolean|integer
 --- @field ignore_whitespace? boolean
 --- @field ignore_whitespace_change? boolean
 --- @field ignore_whitespace_change_at_eol? boolean
diff --git a/runtime/lua/vim/_meta/api_keysets_extra.lua b/runtime/lua/vim/_meta/api_keysets_extra.lua
index 81bce50746..e8e901acb2 100644
--- a/runtime/lua/vim/_meta/api_keysets_extra.lua
+++ b/runtime/lua/vim/_meta/api_keysets_extra.lua
@@ -73,6 +73,51 @@ error('Cannot require a meta file')
 --- @field buflocal? boolean
 --- @field buffer? integer
 
+--- @class vim.api.keyset.create_autocmd.callback_args
+--- @field id integer autocommand id
+--- @field event string name of the triggered event |autocmd-events|
+--- @field group? integer autocommand group id, if any
+--- @field match string expanded value of <amatch>
+--- @field buf integer expanded value of <abuf>
+--- @field file string expanded value of <afile>
+--- @field data? any arbitrary data passed from |nvim_exec_autocmds()|                       *event-data*
+
+--- @class vim.api.keyset.create_user_command.command_args
+--- @field name string Command name
+---
+--- The args passed to the command, if any <args>
+--- @field args string
+---
+--- The args split by unescaped whitespace
+--- (when more than one argument is allowed), if any <f-args>
+--- @field fargs string[]
+---
+--- Number of arguments |:command-nargs|
+--- @field nargs string
+---
+--- "true" if the command was executed with a ! modifier <bang>
+--- @field bang boolean
+---
+--- The starting line of the command range <line1>
+--- @field line1 integer
+---
+--- The final line of the command range <line2>
+--- @field line2 integer
+---
+--- The number of items in the command range: 0, 1, or 2 <range>
+--- @field range integer
+---
+--- Any count supplied <count>
+--- @field count integer
+--- The optional register, if specified <reg>
+--- @field reg string
+--- Command modifiers, if any <mods>
+--- @field mods string
+---
+--- Command modifiers in a structured format. Has the same structure as the
+--- "mods" key of |nvim_parse_cmd()|.
+--- @field smods table
+
 --- @class vim.api.keyset.command_info
 --- @field name string
 --- @field definition string
diff --git a/scripts/gen_eval_files.lua b/scripts/gen_eval_files.lua
index a9431ae2e5..498bf6b26f 100755
--- a/scripts/gen_eval_files.lua
+++ b/scripts/gen_eval_files.lua
@@ -47,6 +47,18 @@ local LUA_API_RETURN_OVERRIDES = {
   nvim_win_get_config = 'vim.api.keyset.win_config',
 }
 
+local LUA_API_KEYSET_OVERRIDES = {
+  create_autocmd = {
+    callback = 'string|(fun(args: vim.api.keyset.create_autocmd.callback_args): boolean?)',
+  },
+}
+
+local LUA_API_PARAM_OVERRIDES = {
+  nvim_create_user_command = {
+    command = 'string|fun(args: vim.api.keyset.create_user_command.command_args)',
+  },
+}
+
 local LUA_META_HEADER = {
   '--- @meta _',
   '-- THIS FILE IS GENERATED',
@@ -118,7 +130,7 @@ local API_TYPES = {
   LuaRef = 'function',
   Dict = 'table<string,any>',
   Float = 'number',
-  HLGroupID = 'number|string',
+  HLGroupID = 'integer|string',
   void = '',
 }
 
@@ -133,6 +145,10 @@ end
 --- @param t string
 --- @return string
 local function api_type(t)
+  if vim.startswith(t, '*') then
+    return api_type(t:sub(2)) .. '?'
+  end
+
   local as0 = t:match('^ArrayOf%((.*)%)')
   if as0 then
     local as = split(as0, ', ')
@@ -149,6 +165,33 @@ local function api_type(t)
     return 'table<string,' .. api_type(d0) .. '>'
   end
 
+  local u = t:match('^Union%((.*)%)')
+  if u then
+    local us = vim.split(u, ',%s*')
+    return table.concat(vim.tbl_map(api_type, us), '|')
+  end
+
+  local l = t:match('^LuaRefOf%((.*)%)')
+  if l then
+    --- @type string
+    l = l:gsub('%s+', ' ')
+    --- @type string?, string?
+    local as, r = l:match('%((.*)%),%s*(.*)')
+    if not as then
+      --- @type string
+      as = assert(l:match('%((.*)%)'))
+    end
+
+    local as1 = {} --- @type string[]
+    for a in vim.gsplit(as, ',%s') do
+      local a1 = vim.split(a, '%s+', { trimempty = true })
+      local nm = a1[2]:gsub('%*(.*)$', '%1?')
+      as1[#as1 + 1] = nm .. ': ' .. api_type(a1[1])
+    end
+
+    return ('fun(%s)%s'):format(table.concat(as1, ', '), r and ': ' .. api_type(r) or '')
+  end
+
   return API_TYPES[t] or t
 end
 
@@ -251,11 +294,13 @@ local function get_api_meta()
       sees[#sees + 1] = see.desc
     end
 
+    local pty_overrides = LUA_API_PARAM_OVERRIDES[fun.name] or {}
+
     local params = {} --- @type [string,string][]
     for _, p in ipairs(fun.params) do
       params[#params + 1] = {
         p.name,
-        api_type(p.type),
+        api_type(pty_overrides[p.name] or p.type),
         not deprecated and p.desc or nil,
       }
     end
@@ -382,9 +427,11 @@ local function get_api_keysets_meta()
   local keysets = metadata.keysets
 
   for _, k in ipairs(keysets) do
+    local pty_overrides = LUA_API_KEYSET_OVERRIDES[k.name] or {}
     local params = {}
     for _, key in ipairs(k.keys) do
-      table.insert(params, { key .. '?', api_type(k.types[key] or 'any') })
+      local pty = pty_overrides[key] or k.types[key] or 'any'
+      table.insert(params, { key .. '?', api_type(pty) })
     end
     ret[k.name] = {
       signature = 'NA',
diff --git a/src/nvim/api/autocmd.c b/src/nvim/api/autocmd.c
index 22932fd1a2..db87500d08 100644
--- a/src/nvim/api/autocmd.c
+++ b/src/nvim/api/autocmd.c
@@ -631,7 +631,7 @@ Integer nvim_create_augroup(uint64_t channel_id, String name, Dict(create_augrou
   FUNC_API_SINCE(9)
 {
   char *augroup_name = name.data;
-  bool clear_autocmds = api_object_to_bool(opts->clear, "clear", true, err);
+  bool clear_autocmds = GET_BOOL_OR_TRUE(opts, create_augroup, clear);
 
   int augroup = -1;
   WITH_SCRIPT_CONTEXT(channel_id, {
diff --git a/src/nvim/api/command.c b/src/nvim/api/command.c
index ab57d5c009..709e18af73 100644
--- a/src/nvim/api/command.c
+++ b/src/nvim/api/command.c
@@ -226,8 +226,8 @@ Dict(cmd) nvim_parse_cmd(String str, Dict(empty) *opts, Arena *arena, Error *err
     addr = "?";
     break;
   }
-  PUT_KEY(result, cmd, addr, CSTR_AS_OBJ(addr));
-  PUT_KEY(result, cmd, nextcmd, CSTR_AS_OBJ(ea.nextcmd));
+  PUT_KEY(result, cmd, addr, cstr_as_string(addr));
+  PUT_KEY(result, cmd, nextcmd, cstr_as_string(ea.nextcmd));
 
   // TODO(bfredl): nested keydict would be nice..
   Dict mods = arena_dict(arena, 20);
diff --git a/src/nvim/api/keysets_defs.h b/src/nvim/api/keysets_defs.h
index 96aabb851f..48f5f7246c 100644
--- a/src/nvim/api/keysets_defs.h
+++ b/src/nvim/api/keysets_defs.h
@@ -8,18 +8,18 @@ typedef struct {
 
 typedef struct {
   OptionalKeys is_set__context_;
-  Array types;
+  ArrayOf(String) types;
 } Dict(context);
 
 typedef struct {
   OptionalKeys is_set__set_decoration_provider_;
-  LuaRef on_start;
-  LuaRef on_buf;
-  LuaRef on_win;
-  LuaRef on_line;
-  LuaRef on_end;
-  LuaRef _on_hl_def;
-  LuaRef _on_spell_nav;
+  LuaRefOf(("start" _, Integer tick)) on_start;
+  LuaRefOf(("buf" _, Integer bufnr, Integer tick)) on_buf;
+  LuaRefOf(("win" _, Integer winid, Integer bufnr, Integer toprow, Integer botrow)) on_win;
+  LuaRefOf(("line" _, Integer winid, Integer bufnr, Integer row)) on_line;
+  LuaRefOf(("end" _, Integer tick)) on_end;
+  LuaRefOf(("hl_def" _)) _on_hl_def;
+  LuaRefOf(("spell_nav" _)) _on_spell_nav;
 } Dict(set_decoration_provider);
 
 typedef struct {
@@ -116,7 +116,7 @@ typedef struct {
   String relative;
   String split;
   Window win;
-  Array bufpos;
+  ArrayOf(Integer) bufpos;
   Boolean external;
   Boolean focusable;
   Boolean mouse;
@@ -172,17 +172,17 @@ typedef struct {
   Boolean altfont;
   Boolean nocombine;
   Boolean default_ DictKey(default);
-  Object cterm;
-  Object foreground;
-  Object fg;
-  Object background;
-  Object bg;
-  Object ctermfg;
-  Object ctermbg;
-  Object special;
-  Object sp;
-  Object link;
-  Object global_link;
+  Union(Integer, String) cterm;
+  Union(Integer, String) foreground;
+  Union(Integer, String) fg;
+  Union(Integer, String) background;
+  Union(Integer, String) bg;
+  Union(Integer, String) ctermfg;
+  Union(Integer, String) ctermbg;
+  Union(Integer, String) special;
+  Union(Integer, String) sp;
+  HLGroupID link;
+  HLGroupID global_link;
   Boolean fallback;
   Integer blend;
   Boolean fg_indexed;
@@ -230,9 +230,9 @@ typedef struct {
 typedef struct {
   OptionalKeys is_set__clear_autocmds_;
   Buffer buffer;
-  Object event;
-  Object group;
-  Object pattern;
+  Union(String, ArrayOf(String)) event;
+  Union(Integer, String) group;
+  Union(String, ArrayOf(String)) pattern;
 } Dict(clear_autocmds);
 
 typedef struct {
@@ -241,31 +241,32 @@ typedef struct {
   Object callback;
   String command;
   String desc;
-  Object group;
+  Union(Integer, String) group;
   Boolean nested;
   Boolean once;
-  Object pattern;
+  Union(String, ArrayOf(String)) pattern;
 } Dict(create_autocmd);
 
 typedef struct {
   OptionalKeys is_set__exec_autocmds_;
   Buffer buffer;
-  Object group;
+  Union(Integer, String) group;
   Boolean modeline;
-  Object pattern;
+  Union(String, ArrayOf(String)) pattern;
   Object data;
 } Dict(exec_autocmds);
 
 typedef struct {
   OptionalKeys is_set__get_autocmds_;
-  Object event;
-  Object group;
-  Object pattern;
-  Object buffer;
+  Union(String, ArrayOf(String)) event;
+  Union(Integer, String) group;
+  Union(String, ArrayOf(String)) pattern;
+  Union(Integer, ArrayOf(Integer)) buffer;
 } Dict(get_autocmds);
 
 typedef struct {
-  Object clear;
+  OptionalKeys is_set__create_augroup_;
+  Boolean clear;
 } Dict(create_augroup);
 
 typedef struct {
@@ -275,12 +276,12 @@ typedef struct {
   Integer count;
   String reg;
   Boolean bang;
-  Array args;
+  ArrayOf(String) args;
   Dict magic;
   Dict mods;
-  Object nargs;
-  Object addr;
-  Object nextcmd;
+  Union(Integer, String) nargs;
+  String addr;
+  String nextcmd;
 } Dict(cmd);
 
 typedef struct {
@@ -333,11 +334,30 @@ typedef struct {
 
 typedef struct {
   OptionalKeys is_set__buf_attach_;
-  LuaRef on_lines;
-  LuaRef on_bytes;
-  LuaRef on_changedtick;
-  LuaRef on_detach;
-  LuaRef on_reload;
+  LuaRefOf(("lines" _,
+            Integer bufnr,
+            Integer changedtick,
+            Integer first,
+            Integer last_old,
+            Integer last_new,
+            Integer byte_count,
+            Integer *deleted_codepoints,
+            Integer *deleted_codeunits), *Boolean) on_lines;
+  LuaRefOf(("bytes" _,
+            Integer bufnr,
+            Integer changedtick,
+            Integer start_row,
+            Integer start_col,
+            Integer start_byte,
+            Integer old_end_row,
+            Integer old_end_col,
+            Integer old_end_byte,
+            Integer new_end_row,
+            Integer new_end_col,
+            Integer new_end_byte), *Boolean) on_bytes;
+  LuaRefOf(("changedtick" _, Integer bufnr, Integer changedtick)) on_changedtick;
+  LuaRefOf(("detach" _, Integer bufnr)) on_detach;
+  LuaRefOf(("reload" _, Integer bufnr)) on_reload;
   Boolean utf_sizes;
   Boolean preview;
 } Dict(buf_attach);
@@ -350,7 +370,7 @@ typedef struct {
 
 typedef struct {
   OptionalKeys is_set__open_term_;
-  LuaRef on_input;
+  LuaRefOf(("input" _, Integer term, Integer bufnr, any data)) on_input;
   Boolean force_crlf;
 } Dict(open_term);
 
@@ -361,12 +381,13 @@ typedef struct {
 
 typedef struct {
   OptionalKeys is_set__xdl_diff_;
-  LuaRef on_hunk;
+  LuaRefOf((Integer start_a, Integer count_a, Integer start_b, Integer count_b),
+           *Integer) on_hunk;
   String result_type;
   String algorithm;
   Integer ctxlen;
   Integer interhunkctxlen;
-  Object linematch;
+  Union(Boolean, Integer) linematch;
   Boolean ignore_whitespace;
   Boolean ignore_whitespace_change;
   Boolean ignore_whitespace_change_at_eol;
diff --git a/src/nvim/api/private/defs.h b/src/nvim/api/private/defs.h
index 26d5ac09a8..6dee86dcf5 100644
--- a/src/nvim/api/private/defs.h
+++ b/src/nvim/api/private/defs.h
@@ -21,6 +21,8 @@
 # define Dict(name) KeyDict_##name
 # define DictHash(name) KeyDict_##name##_get_field
 # define DictKey(name)
+# define LuaRefOf(...) LuaRef
+# define Union(...) Object
 # include "api/private/defs.h.inline.generated.h"
 #endif
 
diff --git a/src/nvim/generators/c_grammar.lua b/src/nvim/generators/c_grammar.lua
index ed6e30ea10..a0a9c86789 100644
--- a/src/nvim/generators/c_grammar.lua
+++ b/src/nvim/generators/c_grammar.lua
@@ -3,7 +3,7 @@ local lpeg = vim.lpeg
 -- lpeg grammar for building api metadata from a set of header files. It
 -- ignores comments and preprocessor commands and parses a very small subset
 -- of C prototypes with a limited set of types
-local P, R, S = lpeg.P, lpeg.R, lpeg.S
+local P, R, S, V = lpeg.P, lpeg.R, lpeg.S, lpeg.V
 local C, Ct, Cc, Cg = lpeg.C, lpeg.Ct, lpeg.Cc, lpeg.Cg
 
 --- @param pat vim.lpeg.Pattern
@@ -35,9 +35,39 @@ local cdoc_comment = P('///') * opt(Ct(Cg(rep(space) * rep(not_nl), 'comment')))
 local c_preproc = P('#') * rep(not_nl)
 local dllexport = P('DLLEXPORT') * rep1(ws)
 
-local typed_container = ((P('ArrayOf(') + P('DictOf(') + P('Dict(')) * rep1(any - P(')')) * P(')'))
+--- @param x vim.lpeg.Pattern
+local function comma1(x)
+  return x * rep(fill * P(',') * fill * x)
+end
+
+-- Define the grammar
+
+local basic_id = letter * rep(alpha)
+
+local str = P('"') * rep(any - P('"')) * P('"')
+
+--- @param x vim.lpeg.Pattern
+local function paren(x)
+  return P('(') * fill * x * fill * P(')')
+end
+
+-- stylua: ignore start
+local typed_container = P({
+  'S',
+  ID = V('S') + basic_id,
+  S = (
+    (P('Union') * paren(comma1(V('ID'))))
+    + (P('ArrayOf') * paren(basic_id * opt(P(',') * fill * rep1(num))))
+    + (P('DictOf') * paren(basic_id))
+    + (P('LuaRefOf') * paren(
+      paren(comma1((V('ID') + str) * rep1(ws) * opt(P('*')) * basic_id))
+      * opt(P(',') * fill * opt(P('*')) * V('ID'))
+    ))
+    + (P('Dict') * paren(basic_id))),
+})
+-- stylua: ignore end
 
-local c_id = (typed_container + (letter * rep(alpha)))
+local c_id = typed_container + basic_id
 local c_void = P('void')
 
 local c_param_type = (
diff --git a/src/nvim/generators/gen_api_dispatch.lua b/src/nvim/generators/gen_api_dispatch.lua
index a78f746fee..402382acd2 100644
--- a/src/nvim/generators/gen_api_dispatch.lua
+++ b/src/nvim/generators/gen_api_dispatch.lua
@@ -347,12 +347,16 @@ for _, k in ipairs(keysets) do
   local function typename(type)
     if type == 'HLGroupID' then
       return 'kObjectTypeInteger'
+    elseif not type or vim.startswith(type, 'Union') then
+      return 'kObjectTypeNil'
+    elseif vim.startswith(type, 'LuaRefOf') then
+      return 'kObjectTypeLuaRef'
     elseif type == 'StringArray' then
       return 'kUnpackTypeStringArray'
-    elseif type ~= nil then
-      return 'kObjectType' .. type
+    elseif vim.startswith(type, 'ArrayOf') then
+      return 'kObjectTypeArray'
     else
-      return 'kObjectTypeNil'
+      return 'kObjectType' .. type
     end
   end
 
diff --git a/src/nvim/highlight.c b/src/nvim/highlight.c
index 5f0a2e0e4e..b063a7708d 100644
--- a/src/nvim/highlight.c
+++ b/src/nvim/highlight.c
@@ -1075,10 +1075,10 @@ HlAttrs dict2hlattrs(Dict(highlight) *dict, bool use_rgb, int *link_id, Error *e
       return hlattrs;
     }
     if (HAS_KEY_X(dict, global_link)) {
-      *link_id = object_to_hl_id(dict->global_link, "link", err);
+      *link_id = (int)dict->global_link;
       mask |= HL_GLOBAL;
     } else {
-      *link_id = object_to_hl_id(dict->link, "link", err);
+      *link_id = (int)dict->link;
     }
 
     if (ERROR_SET(err)) {