Handle LUA_ERRERR

src/util.rs

@@ -288,10 +288,11 @@ pub unsafe fn handle_error(state: *mut ffi::lua_State, err: c_int) -> Result<()>
                     }
                 }
                 ffi::LUA_ERRERR => {
-                    // This can only happen when rlua's own message handler raises an error, which
-                    // should never happen unless there's a bug. This would also be dangerous as it
-                    // longjmps over Rust frames.
-                    lua_panic!(state, "message handler raised error: {}", err_string);
+                    // The Lua manual documents this error wrongly: It is not raised when a message
+                    // handler errors, but rather when some specific situations regarding stack
+                    // overflow handling occurs. Since it is not very useful do differentiate
+                    // between that and "ordinary" runtime errors, we handle them the same way.
+                    Error::RuntimeError(err_string)
                 }
                 ffi::LUA_ERRMEM => {
                     // This is not impossible to hit, but this library is not set up