Function blast_radius_op 

pub fn blast_radius_op(
    workspace: &Workspace,
    conn: &Connection,
    symbol: Option<&str>,
    file: Option<&str>,
    max_depth: usize,
    limit: usize,
) -> Result<BlastRadiusResult, OpError>

Compute blast radius and likely tests for a symbol, file, or uncommitted git changes.