Implement RFC 3631: add rustdoc doc_cfg features #138907

GuillaumeGomez · 2025-03-24T22:50:33Z

This implementation actually resulted in a lot of simplifications:

All cfg computation is now done in one place: propagate_doc_cfg.rs. Because (trait) impls are not retrieved at the same time as the other items, we cannot perform this computation in the clean process, it needs to be after.
Because there is cfg inheritance, we can keep track of them in one place (in propagate_doc_cfg.rs), meaning we don't need to copy an item's attributes to its children anymore. Only exception: impl items. For them we clone only cfg attributes.
propagate_doc_cfg.rs is also now much simpler, much less need to keep track of parents, since everything we need is handled by the new CfgInfo type.
I also suspect that Cfg::simplify_with could either be removed or at least used directly into propagate_doc_cfg.rs when we compute cfgs. Considering how big the PR already is, I'll do it in a follow-up.

I didn't remove the doc_cfg* features in this PR because some dependencies used in rustc (like stdarch) are using it, so we need to have a nightly released with this PR before I can switch to the new feature.

r? ghost

petrochenkov · 2025-03-25T09:48:06Z

What remains to be done:

I'd also want to block the stabilization on landing #138844 to avoid a stable rustdoc feature relying on externally observable hacks in rustc.
The crater run in #138844 returned mostly clean, so I expect it to land soon.

GuillaumeGomez · 2025-03-25T10:36:45Z

Noted! And that will be a nice improvement, thanks!

Just one thing left for the cfg expansion missing: #[cfg_attr(blabla, derive(Debug))]. In this case, the cfg is not kept in the generated derive items. It's been in my TODO list for a long time now. ^^'

petrochenkov · 2025-03-25T10:49:31Z

Just one thing left for the cfg expansion missing: #[cfg_attr(blabla, derive(Debug))]

Do you mean like in #138515? :)

GuillaumeGomez · 2025-03-25T10:52:03Z

You're my hero! Gonna need to handle this new attribute then. :)

bors · 2025-03-25T17:53:10Z

☔ The latest upstream changes (presumably #138923) made this pull request unmergeable. Please resolve the merge conflicts.

bors · 2025-03-27T19:41:02Z

☔ The latest upstream changes (presumably #138927) made this pull request unmergeable. Please resolve the merge conflicts.

doc_auto_cfg has been removed ``` error[E0557]: feature has been removed --> /home/runner/.cargo/registry/src/index.crates.io-1949cf8c6b5b557f/winit-0.30.12/src/lib.rs:185:29 | 185 | #![cfg_attr(docsrs, feature(doc_auto_cfg, doc_cfg_hide), doc(cfg_hide(doc, docsrs)))] | ^^^^^^^^^^^^ feature has been removed | = note: removed in CURRENT_RUSTC_VERSION; see <rust-lang/rust#138907> for more information = note: merged into `doc_cfg` ``` as a workaround pin to a version predating the change

doc_auto_cfg has been merged into doc_cfg: error[E0557]: feature has been removed --> src/lib.rs:2:40 | 2 | #![cfg_attr(all(doc, nightly), feature(doc_auto_cfg))] // expect nightly for doc | ^^^^^^^^^^^^ feature has been removed | = note: removed in CURRENT_RUSTC_VERSION; see <rust-lang/rust#138907> for more information = note: merged into `doc_cfg` Signed-off-by: Hanna Czenczek <[email protected]>

doc_auto_cfg has been merged into doc_cfg: error[E0557]: feature has been removed --> src/lib.rs:2:40 | 2 | #![cfg_attr(all(doc, nightly), feature(doc_auto_cfg))] // expect nightly for doc | ^^^^^^^^^^^^ feature has been removed | = note: removed in CURRENT_RUSTC_VERSION; see <rust-lang/rust#138907> for more information = note: merged into `doc_cfg` Signed-off-by: Hanna Czenczek <[email protected]> (cherry picked from commit 273e6a2) Signed-off-by: Hanna Czenczek <[email protected]>

#### Problem The docs builds are currently failing due to the changes in <rust-lang/rust#138907>. #### Summary of changes As recommended there, use `doc_cfg` instead of `doc_auto_cfg`.

- [ ] Added a `CHANGELOG.md` entry # Summary Replace the removed `doc_auto_cfg` feature with the `doc_cfg` feature. # Motivation Avoid compilation errors when building documentation. # Details `doc_auto_cfg` was merged into `doc_cfg` in rust-lang/rust#138907. When `docsrs` is enabled, the old `doc_auto_cfg` results in the following errors on the latest nightlies: ``` error[E0557]: feature has been removed --> src/lib.rs:56:29 | 56 | #![cfg_attr(docsrs, feature(doc_auto_cfg))] | ^^^^^^^^^^^^ feature has been removed | = note: removed in CURRENT_RUSTC_VERSION; see <rust-lang/rust#138907> for more information = note: merged into `doc_cfg` ``` ``` error[E0557]: feature has been removed --> rand_core/src/lib.rs:36:29 | 36 | #![cfg_attr(docsrs, feature(doc_auto_cfg))] | ^^^^^^^^^^^^ feature has been removed | = note: removed in CURRENT_RUSTC_VERSION; see <rust-lang/rust#138907> for more information = note: merged into `doc_cfg` ``` The new `doc_cfg` retains the automatic `cfg` generation that `doc_auto_cfg` used to provide.

See rust-lang/rust#138907

* chore(deps): update various dependencies * chore(deps): update checkout and CodSpeedHQ actions * chore(ci): specify mode for `CodSpeedHQ` action * chore!: bump minimum Rust version, `1.82.0` -> `1.88.0` * fix(docs): rename `doc_auto_cfg` attribute See rust-lang/rust#138907 * fix(ci): require `read` permission for crates' token * chore(ci): remove duplicate test for docs * fix * fix(ci): only check if access token is set * fix(ci): better emulate docsrs by not building dependencies --------- Co-authored-by: Jérome Eertmans <[email protected]>

* feat(lock): add support for private packages * refactor(error): rename error variant * feat(core): support installing private package * feat(registry): authenticate all requests if logged in * feat: save correct lockfile entry for private projects * test(core): add install private package test * docs: doc_auto_cfg merged into doc_cfg Ref: rust-lang/rust#138907 * test: add integration test

the `doc_auto_cfg` feature has been subsumed by `doc_cfg`: rust-lang/rust#138907

The `doc_auto_cfg` feature has been subsumed by `doc_cfg`: rust-lang/rust#138907

the `doc_auto_cfg` feature has been subsumed by `doc_cfg`: rust-lang/rust#138907

The `doc_auto_cfg` feature has been subsumed by `doc_cfg`: rust-lang/rust#138907