rfold is the reverse version of fold.
Fold allows iterators to implement a different (non-resumable) internal
iteration when it is more efficient than the external iteration
implemented through the next method. (Common examples are VecDeque and
.chain()).
Introduce rfold() so that the same customization is available for
reverse iteration. This is achieved by both adding the method, and by
having the Rev<I> adaptor connect Rev::rfold -> I::fold, Rev::fold -> I::rfold.
Adaptors are things that take iterators and adapt them into other
iterators. With this definition, fold is just a usual method, because it
doesn't normally make an iterator.
add a lowercase suggestion to unknown_lints
I recently wrote some tests for a clippy lint, copied the (uppercase) lint name into my test file and forgot to toggle the case. This PR adds a suggestion that would have saved me 10 minutes of debugging, so it's likely a net win 🙂 . Also it adds a UI test for the `unknown_lints` lint.
Use hir::ItemLocalId instead of ast::NodeId in rustc::middle::region::CodeExtent.
This is an alternative to @michaelwoerister's #43887, changing `CodeExtent` instead of `ReScope`.
The benefit here is that the same `Region`s are used same-crate and cross-crate, while preserving the incremental recompilation properties of the stable `hir::ItemLocalId`.
Only places which needed to get back to the `ast::NodeId` from `CodeExtent` was its `span` method, used in error reporting - passing the `&RegionMaps` down allowed using `hir_to_node_id`.
`rustc::cfg` and `dataflow` also had to be converted to `hir::ItemLocalId` because of their interactions with `CodeExtent`, especially in `borrowck`, and from that we have 3 more `hir_to_node_id` calls: `cfg::graphviz` node labels, `borrowck` move reporting, and the `unconditional_recursion` lint.
Out of all of those, *only* the lint actually makes a decision (on whether code will compile) based on the result of the conversion, the others only use it to know how to print information to the user.
So I think we're safe to say that the bulk of the code working with a `CodeExtent` is fine with local IDs.
r? @nikomatsakis
add `fn` to syntax of rustc::ty::maps::define_maps
This is not a functional change, it just makes it possible to find a query by grepping without knowing that it's a query rather than a function.
I didn't pursue renaming everything from "map" to "query" because it seems to be a very invasive change. It would be a good test to exercise an IDE's renaming features.
Closes#44161
r? @eddyb
rustbuild: update the rust-src filter for compiler-rt
We wanted `src/compiler-rt/test` filtered from the `rust-src` package,
but that path is now `src/libcompiler_builtins/compiler-rt/test`. This
saves over half of the installed rust-src size. (50MB -> 22MB)
We wanted `src/compiler-rt/test` filtered from the `rust-src` package,
but that path is now `src/libcompiler_builtins/compiler-rt/test`. This
saves over half of the installed rust-src size. (50MB -> 22MB)
