Method format_boolean

datafusion/spark/src/function/string/format_string.rs:1718–1744

(&self, writer: &mut String, value: &Option<bool>)

    }

    fn format_boolean(&self, writer: &mut String, value: &Option<bool>) -> Result<()> {
        let value = value.unwrap_or(false);

        let formatted = match self.conversion_type {
            ConversionType::BooleanUpper => {
                if value {
                    "TRUE"
                } else {
                    "FALSE"
                }
            }
            ConversionType::BooleanLower => {
                if value {
                    "true"
                } else {
                    "false"
                }
            }
            _ => {
                return exec_err!(
                    "Invalid conversion type: {:?} for boolean array",
                    self.conversion_type
                );
            }
        };
        self.format_str(writer, formatted)
    }

    fn format_float(&self, writer: &mut String, value: f64) -> Result<()> {
        self.validate_grouping_separator()?;