syntax_data: {"ast_node_type":"other","tokens":[{"end":31,"kind":"keyword","start":0,"text":"if"}]}
source_snippet:                     if i == 0 {
context_before:                     // The first arg is the self ty - use the correct span for it.
context_after:                         if let Some(hir::ItemKind::Impl(hir::Impl { self_ty, .. })) =