Method run

crates/sats/src/buffer.rs:333–338

Run `work` on `writer`, but also count the number of bytes written.

(writer: W, work: impl FnOnce(&mut TeeWriter<W, CountWriter>) -> R)

impl CountWriter {
    /// Run `work` on `writer`, but also count the number of bytes written.
    pub fn run<W: BufWriter, R>(writer: W, work: impl FnOnce(&mut TeeWriter<W, CountWriter>) -> R) -> (R, usize) {
        let counter = Self::default();
        let mut writer = TeeWriter::new(writer, counter);
        let ret = work(&mut writer);
        (ret, writer.w2.finish())
    }

    /// Consumes the counter and returns the final count.
    pub fn finish(self) -> usize {