syntax_data: {"ast_node_type":"other","tokens":[{"end":23,"kind":"keyword","start":0,"text":"assert_eq!("}]}
source_snippet:             assert_eq!(
context_before:                 Tree::def(Def::NoSafetyInvariants).then(Tree::def(Def::HasSafetyInvariants));
context_after:                 layout.prune(&|d| matches!(d, Def::HasSafetyInvariants)),