Method reduce

crates/ruff_python_stdlib/src/open_mode.rs:69–88

(self)

    /// Remove any redundant flags from the open mode.
    #[must_use]
    pub fn reduce(self) -> Self {
        let mut open_mode = self;

        // `t` is always redundant.
        open_mode.remove(Self::TEXT);

        // `U` is always redundant.
        open_mode.remove(Self::UNIVERSAL_NEWLINES);

        // `r` is redundant, unless `b` or `+` is also set, in which case, we need one of `w`, `a`, `r`, or `x`.
        if open_mode.intersects(Self::BINARY | Self::PLUS) {
            if !open_mode.intersects(Self::WRITE | Self::CREATE | Self::APPEND) {
                open_mode.insert(Self::READ);
            }
        } else {
            open_mode.remove(Self::READ);
        }

        open_mode
    }
}

/// Write the [`OpenMode`] as a string.