rustdoc: Populate external_traits with traits only seen in impls
This means default methods can always be found and "Important traits" will include all spotlight traits.
No longer parse it.
Remove AutoTrait variant from AST and HIR.
Remove backwards compatibility lint.
Remove coherence checks, they make no sense for the new syntax.
Remove from rustdoc.
rustdoc: Add missing src links for generic impls on trait pages
`implementor2item` would return `None` for generic impls so instead this clones the entire `clean::Item` into the `implementors` map which simplifies some code.
Issue 46976
ICE is due to an empty path segments, so I set the path to be the same as the in band ty params symbol. (I think this is how regular generics end up being handled?)
Pinging @cramertj, this is your code I'm editing here.
rustdoc: add option to abort the process on markdown differences
In the efforts of keeping the std docs free of markdown warnings, this PR adds a stopgap measure to make sure the CI fails if it detects a markdown difference. It does this by adding a new unstable flag to rustdoc, `--deny-render-differences`, which bootstrap then passes to rustdoc when documenting std and friends.
The implementation is... probably not the cleanest option. It currently adds an extra branch after it prints the markdown warnings, which just prints a final line and calls `::std::process::abort(1)`. I did it like this because if it just panics regularly, it looks like an ICE, an even though `html::render::run` returns a Result, that Result is also just `expect`ed immediately, generating the same problem. This way bypasses the panic handler at the top of the thread and looks like a proper failure. Since i don't have a real error Handler there, this is the best i can do without pulling in a real error system for rustdoc.
This PR is blocked on https://github.com/rust-lang/rust/pull/46853, which will fix the rendering differences that were present on master when i started this branch.
`implementor2item` would return `None` for generic impls so instead this clones the entire `clean::Item` into the `implementors` map which simplifies some code.
The Generics now contain one Vec of an enum for the generic parameters,
rather than two separate Vec's for lifetime and type parameters.
Additionally, places that previously used Vec<LifetimeDef> now use
Vec<GenericParam> instead.
The `--sort-modules-by-appearance` option will list modules in the
order that they appear in the source, rather than sorting them
alphabetically (as is the default). This resolves#8552.
rustdoc: Fix issues with cross-crate inlined associated items
* Visibility was missing from impl items.
* Attributes and docs were missing from consts and types in impls.
* Const default values were missing from traits.
This unifies the code that handles associated items from impls and traits.
Rustoc item summaries that are headers were not displayed at all because
they started with whitespace.
This PR fixes this and now removes the whitespace and then displays the
block.
* Visibility was missing from impl items.
* Attributes and docs were missing from consts and types in impls.
* Const default values were missing from traits.
This unifies the code that handles associated items from impls and traits.
rustdoc: include external files in documentation (RFC 1990)
Part of https://github.com/rust-lang/rfcs/pull/1990 (needs work on the error reporting, which i'm deferring to after this initial PR)
cc #44732
Also fixes#42760, because the prep work for the error reporting made it easy to fix that at the same time.
show in docs whether the return type of a function impls Iterator/Read/Write
Closes#25928
This PR makes it so that when rustdoc documents a function, it checks the return type to see whether it implements a handful of specific traits. If so, it will print the impl and any associated types. Rather than doing this via a whitelist within rustdoc, i chose to do this by a new `#[doc]` attribute parameter, so things like `Future` could tap into this if desired.
### Known shortcomings
~~The printing of impls currently uses the `where` class over the whole thing to shrink the font size relative to the function definition itself. Naturally, when the impl has a where clause of its own, it gets shrunken even further:~~ (This is no longer a problem because the design changed and rendered this concern moot.)
The lookup currently just looks at the top-level type, not looking inside things like Result or Option, which renders the spotlights on Read/Write a little less useful:
<details><summary>`File::{open, create}` don't have spotlight info (pic of old design)</summary>
</details>
All three of the initially spotlighted traits are generically implemented on `&mut` references. Rustdoc currently treats a `&mut T` reference-to-a-generic as an impl on the reference primitive itself. `&mut Self` counts as a generic in the eyes of rustdoc. All this combines to create this lovely scene on `Iterator::by_ref`:
<details><summary>`Iterator::by_ref` spotlights Iterator, Read, and Write (pic of old design)</summary>
</details>
