Updating crates.io index with `net.git-fetch-with-cli` option enabled should show progress

[kawaemon]

Problem

If user doesn't use net.git-fetch-with-cli option, cargo shows the progress bar.
However it doesn't show anything and stalls up to some minutes (at least looks like so) with that option enabled.

It may make users feel anxious, so I think it should show progress somehow too.

❯ cargo add tokio
    Updating crates.io index
       Fetch [                         ]   2.28%, 258.75KiB/s

❯ CARGO_NET_GIT_FETCH_WITH_CLI=true cargo add tokio
    Updating crates.io index

Proposed Solution

I think redirecting git's stdout to user is reasonable solution.

It is the best if we could parse git's output and show the progress bar used in normal fetch, but it might be too expensive to implement.

Notes

No response

[weihanglo]

It sounds like a good enhancement to me!

The git CLI is invoked here.

cargo/src/cargo/sources/git/utils.rs

Lines 924 to 930 in abc6abe

	fn fetch_with_cli(
	repo: &mut git2::Repository,
	url: &str,
	refspecs: &[String],
	tags: bool,
	config: &Config,
	) -> CargoResult<()> {

I guess we need to use exec_with_streaming or something instead to redirect its output. I don't think it is necessary to draw a progress bar for that.

We should also take care of the --quiet and --verbose flags, passing them to git CLI.

[kawaemon]

Thanks!
I want to try to implement this feature. Can I get this assigned to me?
@weihanglo

[weihanglo]

You could use @rustbot to do that. See https://rustc-dev-guide.rust-lang.org/rustbot.html
Feel free to ask any question here or ping me on Zulip.

[kawaemon]

@rustbot claim

[kawaemon]

@weihanglo thanks!