syntax_data: {"ast_node_type":"other","tokens":[{"end":54,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // `is_root` here is a fast path optimization.
context_before:         // Combining locations typically doesn't make sense in case of context mismatches.
context_after:         let a_is_callsite = a.ctxt.is_root() || a.ctxt == b.span().source_callsite().ctxt();