Method buildContext

valdi/src/valdi/runtime/JavaScript/JavaScriptRuntime.cpp:2221–2436

    } else {
        auto result = getContextForId(contextId);
        if (!result) {
            return callContext.throwError(result.moveError());
        }
        newCurrentContext = result.moveValue();
    }

    auto previous = Context::currentRef();
    Context::setCurrent(newCurrentContext);

    _contextsStack.emplace_back(std::move(previous));

    return callContext.getContext().newUndefined();
}

JSValueRef JavaScriptRuntime::runtimePopCurrentContext(JSFunctionNativeCallContext& callContext) {
    if (_contextsStack.empty()) {
        return callContext.throwError(Error("Context stack is empty"));
    }

    auto context = std::move(_contextsStack[_contextsStack.size() - 1]);
    _contextsStack.pop_back();

    Context::setCurrent(std::move(context));

    return callContext.getContext().newUndefined();
}

JSValueRef JavaScriptRuntime::runtimeGetCurrentContext(JSFunctionNativeCallContext& callContext) {
    auto* context = Context::current();
    return callContext.getContext().newNumber(static_cast<int32_t>(context->getContextId()));
}

JSValueRef JavaScriptRuntime::runtimeSaveCurrentContext(JSFunctionNativeCallContext& callContext) {
    // store the current context
    auto context = Context::currentRef();
    _contextsStash.emplace_back(context);
    // and return its id so that it can be used to restore it
    return callContext.getContext().newNumber(static_cast<int32_t>(context->getContextId()));
}

JSValueRef JavaScriptRuntime::runtimeRestoreCurrentContext(JSFunctionNativeCallContext& callContext) {
    ContextId contextId = getParameterAsContextId(callContext, 0);
    CHECK_CALL_CONTEXT(callContext);
    // scan the vector of saved contexts for a matching id
    for (auto i = _contextsStash.begin(); i != _contextsStash.end(); ++i) {
        if ((*i)->getContextId() == contextId) {
            // apply current context
            Context::setCurrent(*i);
            // swap the target context with the context at the end
            // this is safe because we know the vector is not empty
            std::swap(*i, _contextsStash.back());
            // delete the last element from the vector
            _contextsStash.pop_back();
            break;
        }
    };
    return callContext.getContext().newUndefined();
}