Function unicode_case

datafusion/functions/src/string/common.rs:337–343

(s: &str, lower: bool)

#[inline]
fn unicode_case(s: &str, lower: bool) -> String {
    if lower {
        s.to_lowercase()
    } else {
        s.to_uppercase()
    }
}

fn case_conversion(
    args: &[ColumnarValue],