"the lock file needs to be updated but --locked was passed to prevent this" error message is unhelpful

[nnethercote]

While working on Stylo, several times I have hit this error message:

error: the lock file needs to be updated but --locked was passed to prevent this

This is an unhelpful error message. At the very least, it should print the path to the lock file, because when building Stylo there are multiple lock files and it's not obvious which one is the problem.

If it can print more than that -- e.g. identifying how the lock file needs changing -- that would be even better.

[soig]

I have the same issue

[stale]

As there hasn't been any activity here in over 6 months I've marked this as stale and if no further activity happens for 7 days I will close it.

I'm a bot so this may be in error! If this issue should remain open, could someone (the author, a team member, or any interested party) please comment to that effect?

The team would be especially grateful if such a comment included details such as:

• Is this still relevant?
• If so, what is blocking it?
• Is it known what could be done to help move this forward?

Thank you for contributing!

(The cargo team is currently evaluating the use of Stale bot, and using #6035 as the tracking issue to gather feedback.)

If you're reading this comment from the distant future, fear not if this was closed automatically. If you believe it's still an issue please leave a comment and a team member can reopen this issue. Opening a new issue is also acceptable!

[nnethercote]

This is still relevant.

Also, I'm not a fan of closing bugs/PRs merely due to inactivity. It's too close to CADT for comfort: https://www.jwz.org/blog/2003/02/the-cadt-model/.

[dwijnand]

I think if someone shared a reproduction of this issue it would help it being resolved.

[ehuss]

@dwijnand There are many ways to hit this. A very simple repro:

1. Create a project.
2. Build it to create a lock file.
3. Edit Cargo.toml and change the version of your project (or any change that requires updating the lock file).
4. cargo build --locked

Imagine step 3 happened due to pulling in new changes that you are unaware of the details.

[dwijnand]

Lovely, thank you @ehuss!

Perhaps I'll be able to solve this (no promises).