pub fn prop010_link_strategy(&self) -> impl Strategy<Value = PackageLink<'_>> {
        any::<prop::sample::Index>().prop_map(move |index| {
            // Note that this works because PackageGraph uses petgraph::Graph, not StableGraph. If
            // PackageGraph used StableGraph, a retain_edges call would create holes -- invalid
            // indexes in the middle of the range. Graph compacts edge indexes so that all
            // indexes from 0 to link_count are valid.
            let edge_ix = EdgeIndex::new(index.index(self.link_count()));
            self.edge_ix_to_link(edge_ix)
        })
    }
Returns a `Strategy` that generates random dependency links from this graph.

Requires the `proptest1` feature to be enabled.

## Panics

Panics if there are no dependency edges in this `PackageGraph`.
guppy/src/graph/proptest_helpers.rs