syntax_data: {"ast_node_type":"other","tokens":[{"end":85,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                         // MIR building, and are not needed after InstrumentCoverage.
context_before:                         // These kinds of coverage statements are markers inserted during
context_after:                         CoverageKind::BlockMarker { .. } | CoverageKind::SpanMarker { .. },