Function readEnumValues

pj_scripting/src/luau_engine.cpp:237–262

Reads the `values` array of an enum param (entries are {value=, label=} or a bare string). Leaves the stack as found. `param_idx` is the param descriptor.

// Reads the `values` array of an enum param (entries are {value=, label=} or a
// bare string). Leaves the stack as found. `param_idx` is the param descriptor.
void readEnumValues(lua_State* L, int param_idx, ParamSpec& spec) {
  lua_rawgetfield(L, param_idx, "values");
  if (lua_istable(L, -1)) {
    const int values_idx = lua_gettop(L);
    const int count = arrayLen(L, values_idx);
    for (int i = 1; i <= count; ++i) {
      lua_rawgeti(L, values_idx, i);
      const int entry = lua_gettop(L);
      EnumValue ev;
      if (lua_istable(L, entry)) {
        lua_rawgetfield(L, entry, "value");
        ev.value = luaScalarToJson(L, lua_gettop(L));
        lua_pop(L, 1);
        ev.label = stringField(L, entry, "label", jsonScalarToString(ev.value));
      } else {  // a bare scalar entry: value == label
        ev.value = luaScalarToJson(L, entry);
        ev.label = jsonScalarToString(ev.value);
      }
      lua_pop(L, 1);  // entry
      if (!ev.value.is_null()) {
        spec.values.push_back(std::move(ev));
      }
    }
  }
  lua_pop(L, 1);  // values
}

// Parse the `parameters` array of the class table at `class_idx` into specs.
// Returns an error string on a malformed entry, empty on success.