syntax_data: {"ast_node_type":"other","tokens":[{"end":67,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:         // already done, and we just return the Arc we built above.
context_before:         // So we do small read to a fixed-size buffer. If the read returns no bytes then we're
context_after:         // If the read returns bytes however, we just fall back to reading into a Vec then turning