Issue #21450 has been reported by Stranger6667 (Dmitry Dygalo). ---------------------------------------- Bug #21450: Inconsistent `upcase` between `String` and `Symbol` https://bugs.ruby-lang.org/issues/21450 * Author: Stranger6667 (Dmitry Dygalo) * Status: Open * ruby -v: 3.4 * Backport: 3.2: UNKNOWN, 3.3: UNKNOWN, 3.4: UNKNOWN ---------------------------------------- Behavior for `Symbol#upcase` and `String#upcase` differs for `i` character if the `:turkic` is present I'd expect `val.upcase(:turkic)` behaves consistently for both cases: ```ruby 'i'.upcase(:turkic) # "İ" with dot :i.upcase(:turkic) # :I no dot ``` However, when a non-ASCII character is present, then the mapping on `Symbol` works the same way as with `String`: ```ruby :iФ.upcase(:turkic) # :İФ # with dot ``` -- https://bugs.ruby-lang.org/