@Override
    public Response push(Context context, Shape shape, Receiver next) {
        // Do not fail on invalid variable access.
        for (Shape v : getShapes(context)) {
            if (next.apply(context, v) == Response.STOP) {
                // Propagate the signal to stop upstream.
                return Response.STOP;
            }
        }

        return Response.CONTINUE;
    }
Pushes the shapes stored in a specific variable to the next selector.
smithy-model/src/main/java/software/amazon/smithy/model/selector/VariableGetSelector.java