fix(lua): vim.wait(math.huge) fails #36885

Problem:
`nlua_wait()` uses `luaL_checkinteger()` which doesn't support
`math.huge` since it's double type. On PUC Lua this fails with
'number has no integer representation' error and on LuaJIT this
overflows int.

Solution:
Use `luaL_checknumber()` and handle `math.huge`.

(cherry picked from commit bc0635a9fc)

src/nvim/lua/executor.c

@@ -3,6 +3,7 @@
 #include <lauxlib.h>
 #include <lua.h>
 #include <lualib.h>
+#include <math.h>
 #include <stddef.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -437,10 +438,19 @@ static int nlua_wait(lua_State *lstate)
     return luaL_error(lstate, e_fast_api_disabled, "vim.wait");
   }
 
-  intptr_t timeout = luaL_checkinteger(lstate, 1);
-  if (timeout < 0) {
+  double timeout_number = luaL_checknumber(lstate, 1);
+  if (timeout_number < 0) {
     return luaL_error(lstate, "timeout must be >= 0");
   }
+  int64_t timeout;
+  if (isinf(timeout_number) || timeout_number > (double)INT64_MAX) {
+    timeout = INT64_MAX;
+  } else {
+    if (isnan(timeout_number) || timeout_number != trunc(timeout_number)) {
+      return luaL_error(lstate, "timeout has no integer representation");
+    }
+    timeout = (int64_t)timeout_number;
+  }
 
   int lua_top = lua_gettop(lstate);
 
@@ -496,7 +506,7 @@ static int nlua_wait(lua_State *lstate)
 
   LOOP_PROCESS_EVENTS_UNTIL(&main_loop,
                             loop_events,
-                            (int)timeout,
+                            timeout,
                             got_int || (is_function ? nlua_wait_condition(lstate,
                                                                           &pcall_status,
                                                                           &callback_result)

test/functional/lua/vim_spec.lua

@@ -3768,7 +3768,8 @@ stack traceback:
         exec_lua([[
           function _G.Wait()
             vim.rpcnotify(vim.g.channel, 'ready')
-            local _, interrupted = vim.wait(4000)
+            -- handles math.huge #36854
+            local _, interrupted = vim.wait(math.huge)
             vim.rpcnotify(vim.g.channel, 'wait', interrupted)
           end
         ]])
@@ -3782,7 +3783,7 @@ stack traceback:
         exec_lua([[
           function _G.Wait()
             vim.rpcnotify(vim.g.channel, 'ready')
-            local _, interrupted = vim.wait(4000, function() end)
+            local _, interrupted = vim.wait(math.huge, function() end)
             vim.rpcnotify(vim.g.channel, 'wait', interrupted)
           end
         ]])