History of plural 1 change

In src/cli/format.rs, lines 19–21 on 073a2115995fa07bb7e407ac76c0ac85fe77804165c9c0416a4ee27b680f28a8. Every change that wrote or deleted one of these lines, or deleted a line from between them. Exact, because each line keeps its identity across edits; edits elsewhere in the file are not here. Also: oxy log -L 19,21:src/cli/format.rs.