Parse a supergraph to get subgraphs?

Is there any way to get which subgraphs a supergraph has?
And I mean not through apollo studio.
Can this be done through rover or is there any other tool that can parse a supergraph?
Sure, you can introspect the supergraph and then look for this in the file, but we need this to be done with bash script or similar.

enum join__Graph {
SUBGRAPHA @join__graph(name: “subgraph_a”, url: “https://subgraph_a_url”)
SUBGRAPHB @join__graph(name: “subgraph_b”, url: “https://subgraph_b_url”)