Update lock_api and instant to most recent versions

[j-vanderstoep]

lock_api is updated from 0.4.0 to 0.4.1.
instant is upsated from 0.1.4 to 0.1.7.

[j-vanderstoep]

Thanks for maintaining this crate. Some additional context for this change:

We're considering parking_lot for use in the Android open source project [1]. For Android, it's important that we limit the number of crate versions that are used because that reduces both memory and disk usage, both of critical importance on resource-constrained Android devices. Generally we try to achieve that by only depending on the latest version of each crate that we directly or indirectly use. This change moves us to the most recent version of lock_api and instant crates.

[1] https://android-review.googlesource.com/c/platform/external/rust/crates/parking_lot/+/1460364

[CryZe]

This should not be necessary, cargo will never select both 0.1.4 and 0.1.7 as incompatible crates were it would compile in both versions.

[j-vanderstoep]

This should not be necessary, cargo will never select both 0.1.4 and 0.1.7 as incompatible crates were it would compile in both versions.

I'm not sure I understand what you mean. If project A depends in 0.1.4, and project B depends on version 0.1.7, cargo will pull in 0.1.4 for project A and 0.1.7 for project B. Which would result in two versions of the same dylib on my device. If instead they both depend on 0.1.7, then I can have both projects depend on the same compiled output.

[CryZe]

That's not the case, if both 0.1.4 and 0.1.7 are depended on cargo will only pull in 0.1.7, unless they both specify them as "=0.1.4" and "=0.1.7" respectively. Unless of course these two projects are separate projects (i.e. two different cargo projects with their own Cargo.lock files) and you are linking them together in some custom way.

[j-vanderstoep]

Isn't that only true if 0.1.4 and 0.1.7 are depended on by the same project (e.g. a single "cargo build" command)? I'm not just concerned about a single project and its dependencies. I want separate/independent projects to rely on the same version of the crate if possible. Or does cargo always pull in the most recent minor version?

[bjorn3]

The Cargo.lock file is used to ensure that the used version of dependencies doesn't change between builds. You can use cargo update to update all dependencies or cargo update -p lock_api to only update lock_api.

[faern]

@j-vanderstoep When you do cargo update it will automatically upgrade all crates to their latest semver compatible versions, depending on how the version in specified in Cargo.toml. Here in parking_lot the version is specified as version = "0.4.0" (one example). This is equivalent to writing version = "^0.4.0". It's called a caret requirement. This allows cargo to pull in any version in this range: >=0.4.0, <0.5.0. Please see the relevant cargo documentation: https://doc.rust-lang.org/cargo/reference/specifying-dependencies.html

So yes, the change the PR makes should not be needed. You should just be able to do cargo update to get the latest versions. As pointed out above you can run it with -p <crate> to only update some crates.

[j-vanderstoep]

Thanks everyone for the explanation. I confirmed locally exactly what you're describing - Even if 0.1.4 is specified, if 0.1.7 exists, Cargo will use that instead.