syntax_data: {"ast_node_type":"other","tokens":[{"end":43,"kind":"keyword","start":0,"text":"//"}]}
source_snippet:             // `-Cmetadata=a -Cmetadata=bc`
context_before:             // different values for `-Cmetadata=ab -Cmetadata=c` and
context_after:             hasher.write_usize(s.len());