An analysis of semver compliance in Rust finds accidental semver violations are common even in the most popular crates. Human error is not the cause, and better tooling is the way forward.
I’m arguing (humbly of course) that intended vs. unintended use of what is at the end of the day a part of the public interface shouldn’t be taken into consideration by default. Otherwise, other cases can be argued as non-breaking too!
Foo was never meant to be sent to other threads, So, losing Send is not a semver- breaking change!
Exhaustive enum Bar is only meant to be matched exhaustively internally. We say so in the docs. So adding a variant to it is not a semver-breaking change!
And giving more powers to a (kludge) doc attribute just doesn’t seem in my eyes to be a generally wise move.
A: cargo-semver is still complaining about this item which I already have cfg-ed under an exp_api crate feature (which I don’t want to rename). CI is failing.
B: PRO-TIP: Just slap a #[doc(hidden)] on it and CI will pass!
A: What if I still want to see the docs?
B: We are pushing for --document-hidden-items to stabilize soon. So you can just simply use that!
cargo-semver-check should definitely provide a way to mark syntactically-public items as “de-facto private,” because some projects just need to do bad things and leaving them out in the cold is not helpful. But you’ve convinced me that doc(hidden) is a poor way to do it.
I’m arguing (humbly of course) that intended vs. unintended use of what is at the end of the day a part of the public interface shouldn’t be taken into consideration by default. Otherwise, other cases can be argued as non-breaking too!
Foowas never meant to be sent to other threads, So, losingSendis not a semver- breaking change!Exhaustive enum
Baris only meant to be matched exhaustively internally. We say so in the docs. So adding a variant to it is not a semver-breaking change!And giving more powers to a (kludge) doc attribute just doesn’t seem in my eyes to be a generally wise move.
A:
cargo-semveris still complaining about this item which I already have cfg-ed under anexp_apicrate feature (which I don’t want to rename). CI is failing.B: PRO-TIP: Just slap a
#[doc(hidden)]on it and CI will pass!A: What if I still want to see the docs?
B: We are pushing for --document-hidden-items to stabilize soon. So you can just simply use that!
That’s a good point.
cargo-semver-check should definitely provide a way to mark syntactically-public items as “de-facto private,” because some projects just need to do bad things and leaving them out in the cold is not helpful. But you’ve convinced me that
doc(hidden)is a poor way to do it.