Cannot specify timings in .cargo/config

[jerryc05]

Problem

Cannot specify timings option in .cargo/config

Steps

1. Add these to .cargo/config:

   [build]
   timings = ['html']
   

2. Shows warning: warning: unused config key build.timings, and timings not activated.

Possible Solution(s)

Parse build.timings in .cargo/config since timings is removed from unstable in nightly cargo.

Notes

No response

Version

cargo 1.61.0-nightly (109bfbd 2022-03-17)
release: 1.61.0-nightly
commit-hash: 109bfbd055325ef87a6e7f63d67da7e838f8300b
commit-date: 2022-03-17
host: x86_64-unknown-linux-gnu
libgit2: 1.4.2 (sys:0.14.2 vendored)
libcurl: 7.80.0-DEV (sys:0.4.51+curl-7.80.0 vendored ssl:OpenSSL/1.1.1m)
os: Debian unstable (sid) [64-bit]

<!-- TRIAGEBOT_START -->

<!-- TRIAGEBOT_ASSIGN_START -->

<!-- TRIAGEBOT_ASSIGN_DATA_START$${"user":"hi-rustin"}$$TRIAGEBOT_ASSIGN_DATA_END -->

<!-- TRIAGEBOT_ASSIGN_END -->
<!-- TRIAGEBOT_END -->

[Rustin170506]

@weihanglo @ehuss Is this acceptable? I think I can help to add it.

[ehuss]

Seems like a reasonable addition to me. Roughly the things that need to be done to add this are:

• Add to CargoBuildConfig
• Check the value around here. I'm not sure if it should take the union of options of the config + cli, or if the CLI should override the config. Needs some thought, but since there is only 1 stable option, probably isn't too critical right now.
• Add a test in the timings module.
• Update the config documentation.
• Update the environment variables documentation.
• Add a mention of the config setting in the timings documentation.
• Add a mention of the config setting in the --timings docs. See --jobs as an example of how this is done. Then rebuild the man pages.

[Rustin170506]

@rustbot claim

[epage]

@jerryc05 could you expand on why you are interested in this being in the config? This seems like a transient option for me and the use case for making it more permanent in a file seems unclear.

[Rustin170506]

@jerryc05 Friendly ping~

Could you share your use cases?

[jerryc05]

Ummm its been a long time since I coded in Rust. I guess I was building my Rust coding starter template at that time and would like to have all my options setup in one config file instead of passing arguments.

[Rustin170506]

@epage Maybe we can close this issue now? I think there are no reasonable use cases for this config. Because it's a debugging config, we can always pass it.

[epage]

I'm not quite seeing why this would be put in a starter template as it seems like you wouldn't want timings on every run but only when specifically wanting to measure a build.

If someone does come up with a reason for wanting timings on every run, we can reconsider this. For now, I'm going to close this though as there doesn't seem to be sufficient motivation provided.