syntax_data: {"ast_node_type":"other","tokens":[{"end":71,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:                 // the only part of rustc that tracks MIR -> HIR is the
context_before:                 // Some consumers of rustc need to map MIR locations back to HIR nodes. Currently
context_after:                 // `SourceScopeLocalData::lint_root` field that tracks lint levels for MIR