History of plural 1 change

In src/cli/format.rs, lines 19–21 on ff7c55b5c87b67135de93b27d122915ec38e5c9a0f34727e506691dc891d21a3. 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.