fix: use BufWriter in list command to avoid println! in a loop

[arcstur]

Piping the output of toggl list would panic, probably because of calling println! in a loop, which we should not do:

https://rust-cli.github.io/book/tutorial/output.html#a-note-on-printing-performance

I updated the list command code to use a BufWriter and writeln!. I used expect to deal with writeln errors. I think we could have an error type in the future that absorbs io::Error, what do you think?

Anyway, with this the list command stopped panicking when piping.

[shantanuraj]

This seems to be the source of the issue
rust-lang/rust#46016

[arcstur]

I see, makes sense! But I think it's still better to use writeln! than println! in the loop, right?

[shantanuraj]

Yeah I was just curious about the source of the problem.

Could you share what you're piping toggl list to?

This is the my comparison of main and your pr

[arcstur]

When piping to head it panics for me:

toggl list | head
... # my time entries
thread 'main' panicked at library/std/src/io/stdio.rs:1030:9:
failed printing to stdout: Broken pipe (os error 32)
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace

[shantanuraj]

Hmm I can't reproduce the panic on main

But I'm good with the fix if it works for you.
For reference what operating system / arch are you using?

[arcstur]

I think that's becasuse you have only a few items in there. It panicks when there are more than head needs. If I do head -n 100 it does not panic. Try doing toggl list | head -1

I'm using Arch 6.9.1-arch1-1

[shantanuraj]

With head -1

[shantanuraj]

lgtm; I'll fix the other panic with the keychain and create a release