Update books
## nomicon
4 commits in 8551afbb2ca6f5ea37fe58380318b209785e4e02..55de6fa3c1f331774da19472c9ee57d2ae9eb039
2021-04-01 21:58:50 +0900 to 2021-05-12 00:31:01 +0900
- Clarify some of the language around marking traits safe/unsafe. (rust-lang-nursery/nomicon#268)
- Use pointer 'add' instead of 'offset' (rust-lang-nursery/nomicon#265)
- Adjust Vec to build on stable Rust (rust-lang-nursery/nomicon#223)
- Update link to c++ atomic ordering docs (rust-lang-nursery/nomicon#264)
## reference
3 commits in d23f9da8469617e6c81121d9fd123443df70595d..5aa457bf1b54bd2cd5d4cf49797f29299bdf89a7
2021-04-28 11:16:44 -0700 to 2021-05-05 08:39:22 -0700
- Explicitly state result of compound assignment (rust-lang-nursery/reference#1013)
- Adjust the definition of `target_family` (rust-lang-nursery/reference#1006)
- Fix typo in `Traits` (rust-lang-nursery/reference#1012)
## book
2 commits in 50dd06cb71beb27fdc0eebade5509cdcc1f821ed..55a26488ddefc8433e73a2e8352d70f7a5c7fc2b
2021-04-23 13:21:54 -0500 to 2021-05-09 12:03:18 -0500
- Past-tensify "lead" -> "led" (rust-lang/book#2717)
- Merge pull request rust-lang/book#2718 from rust-lang/update-rustc
## rust-by-example
2 commits in e0a721f5202e6d9bec0aff99f10e44480c0da9e7..5f8c6da200ada77760a2fe1096938ef58151c9a6
2021-04-27 09:32:15 -0300 to 2021-04-29 08:08:01 -0300
- Fix Typo in LRBE section; closesrust-lang/rust-by-example#1434 (rust-lang/rust-by-example#1437)
- Add some tests to cargo/test.md. Partially addresses rust-lang/rust-by-example#1304 (rust-lang/rust-by-example#1438)
## rustc-dev-guide
3 commits in e72b43a64925ce053dc7830e21c1a57ba00499bd..1e6c7fbda4c45e85adf63ff3f82fa9c870b1447f
2021-04-27 12:35:37 -0700 to 2021-05-10 13:38:24 +0900
- Unified CPU Requirements (rust-lang/rustc-dev-guide#1126)
- add 'waiting-for-review' incantation to main contrib page (rust-lang/rustc-dev-guide#1124)
- Link to Zulip search for finding the most recent check-in (rust-lang/rustc-dev-guide#1118)
Update documentation for SharedContext::maybe_collapsed_doc_value
Fixes#85120.
The `doc-collapse` was removed, however, the main crate is always "collapsed", meaning that this function is still needed. I updated the documentation instead to avoid misleading readers.
r? `@jsha`
Move global click handlers to per-element ones.
In rustdoc's main.js, we had an onclick handler for the whole document that would dispatch to handlers for various elements. This change attaches the handlers to the elements that trigger them, instead. This simplifies the code and avoids reimplementing the browser's bubbling functionality.
As part of this change, change from a class to an id for help button.
Move the handlers and associated code for highlighting source lines into source-script.js (and factor out a shared regex).
Demo at https://hoffman-andrews.com/rust/bubble-bubble-toil-and-trouble/std/string/struct.String.html
Note: this conflicts with / depends on #85074. Once that's merged I'll rebase this and resolve conflicts.
Part of #83332. Thanks to `@Manishearth` for the [suggestion to not reimplement bubbling](https://github.com/rust-lang/rust/issues/83332#issuecomment-803497509).
r? `@GuillaumeGomez`
Recover from invalid `struct` item syntax
Parse unsupported "default field const values":
```rust
struct S {
field: Type = const_val,
}
```
Recover from small `:` typo and provide suggestion:
```rust
struct S {
field; Type,
field2= Type,
}
```
Fix `--remap-path-prefix` not correctly remapping `rust-src` component paths and unify handling of path mapping with virtualized paths
This PR fixes#73167 ("Binaries end up containing path to the rust-src component despite `--remap-path-prefix`") by preventing real local filesystem paths from reaching compilation output if the path is supposed to be remapped.
`RealFileName::Named` introduced in #72767 is now renamed as `LocalPath`, because this variant wraps a (most likely) valid local filesystem path.
`RealFileName::Devirtualized` is renamed as `Remapped` to be used for remapped path from a real path via `--remap-path-prefix` argument, as well as real path inferred from a virtualized (during compiler bootstrapping) `/rustc/...` path. The `local_path` field is now an `Option<PathBuf>`, as it will be set to `None` before serialisation, so it never reaches any build output. Attempting to serialise a non-`None` `local_path` will cause an assertion faliure.
When a path is remapped, a `RealFileName::Remapped` variant is created. The original path is preserved in `local_path` field and the remapped path is saved in `virtual_name` field. Previously, the `local_path` is directly modified which goes against its purpose of "suitable for reading from the file system on the local host".
`rustc_span::SourceFile`'s fields `unmapped_path` (introduced by #44940) and `name_was_remapped` (introduced by #41508 when `--remap-path-prefix` feature originally added) are removed, as these two pieces of information can be inferred from the `name` field: if it's anything other than a `FileName::Real(_)`, or if it is a `FileName::Real(RealFileName::LocalPath(_))`, then clearly `name_was_remapped` would've been false and `unmapped_path` would've been `None`. If it is a `FileName::Real(RealFileName::Remapped{local_path, virtual_name})`, then `name_was_remapped` would've been true and `unmapped_path` would've been `Some(local_path)`.
cc `@eddyb` who implemented `/rustc/...` path devirtualisation
Implement span quoting for proc-macros
This PR implements span quoting, allowing proc-macros to produce spans
pointing *into their own crate*. This is used by the unstable
`proc_macro::quote!` macro, allowing us to get error messages like this:
```
error[E0412]: cannot find type `MissingType` in this scope
--> $DIR/auxiliary/span-from-proc-macro.rs:37:20
|
LL | pub fn error_from_attribute(_args: TokenStream, _input: TokenStream) -> TokenStream {
| ----------------------------------------------------------------------------------- in this expansion of procedural macro `#[error_from_attribute]`
...
LL | field: MissingType
| ^^^^^^^^^^^ not found in this scope
|
::: $DIR/span-from-proc-macro.rs:8:1
|
LL | #[error_from_attribute]
| ----------------------- in this macro invocation
```
Here, `MissingType` occurs inside the implementation of the proc-macro
`#[error_from_attribute]`. Previosuly, this would always result in a
span pointing at `#[error_from_attribute]`
This will make many proc-macro-related error message much more useful -
when a proc-macro generates code containing an error, users will get an
error message pointing directly at that code (within the macro
definition), instead of always getting a span pointing at the macro
invocation site.
This is implemented as follows:
* When a proc-macro crate is being *compiled*, it causes the `quote!`
macro to get run. This saves all of the sapns in the input to `quote!`
into the metadata of *the proc-macro-crate* (which we are currently
compiling). The `quote!` macro then expands to a call to
`proc_macro::Span::recover_proc_macro_span(id)`, where `id` is an
opaque identifier for the span in the crate metadata.
* When the same proc-macro crate is *run* (e.g. it is loaded from disk
and invoked by some consumer crate), the call to
`proc_macro::Span::recover_proc_macro_span` causes us to load the span
from the proc-macro crate's metadata. The proc-macro then produces a
`TokenStream` containing a `Span` pointing into the proc-macro crate
itself.
The recursive nature of 'quote!' can be difficult to understand at
first. The file `src/test/ui/proc-macro/quote-debug.stdout` shows
the output of the `quote!` macro, which should make this eaier to
understand.
This PR also supports custom quoting spans in custom quote macros (e.g.
the `quote` crate). All span quoting goes through the
`proc_macro::quote_span` method, which can be called by a custom quote
macro to perform span quoting. An example of this usage is provided in
`src/test/ui/proc-macro/auxiliary/custom-quote.rs`
Custom quoting currently has a few limitations:
In order to quote a span, we need to generate a call to
`proc_macro::Span::recover_proc_macro_span`. However, proc-macros
support renaming the `proc_macro` crate, so we can't simply hardcode
this path. Previously, the `quote_span` method used the path
`crate::Span` - however, this only works when it is called by the
builtin `quote!` macro in the same crate. To support being called from
arbitrary crates, we need access to the name of the `proc_macro` crate
to generate a path. This PR adds an additional argument to `quote_span`
to specify the name of the `proc_macro` crate. Howver, this feels kind
of hacky, and we may want to change this before stabilizing anything
quote-related.
Additionally, using `quote_span` currently requires enabling the
`proc_macro_internals` feature. The builtin `quote!` macro
has an `#[allow_internal_unstable]` attribute, but this won't work for
custom quote implementations. This will likely require some additional
tricks to apply `allow_internal_unstable` to the span of
`proc_macro::Span::recover_proc_macro_span`.
This PR implements span quoting, allowing proc-macros to produce spans
pointing *into their own crate*. This is used by the unstable
`proc_macro::quote!` macro, allowing us to get error messages like this:
```
error[E0412]: cannot find type `MissingType` in this scope
--> $DIR/auxiliary/span-from-proc-macro.rs:37:20
|
LL | pub fn error_from_attribute(_args: TokenStream, _input: TokenStream) -> TokenStream {
| ----------------------------------------------------------------------------------- in this expansion of procedural macro `#[error_from_attribute]`
...
LL | field: MissingType
| ^^^^^^^^^^^ not found in this scope
|
::: $DIR/span-from-proc-macro.rs:8:1
|
LL | #[error_from_attribute]
| ----------------------- in this macro invocation
```
Here, `MissingType` occurs inside the implementation of the proc-macro
`#[error_from_attribute]`. Previosuly, this would always result in a
span pointing at `#[error_from_attribute]`
This will make many proc-macro-related error message much more useful -
when a proc-macro generates code containing an error, users will get an
error message pointing directly at that code (within the macro
definition), instead of always getting a span pointing at the macro
invocation site.
This is implemented as follows:
* When a proc-macro crate is being *compiled*, it causes the `quote!`
macro to get run. This saves all of the sapns in the input to `quote!`
into the metadata of *the proc-macro-crate* (which we are currently
compiling). The `quote!` macro then expands to a call to
`proc_macro::Span::recover_proc_macro_span(id)`, where `id` is an
opaque identifier for the span in the crate metadata.
* When the same proc-macro crate is *run* (e.g. it is loaded from disk
and invoked by some consumer crate), the call to
`proc_macro::Span::recover_proc_macro_span` causes us to load the span
from the proc-macro crate's metadata. The proc-macro then produces a
`TokenStream` containing a `Span` pointing into the proc-macro crate
itself.
The recursive nature of 'quote!' can be difficult to understand at
first. The file `src/test/ui/proc-macro/quote-debug.stdout` shows
the output of the `quote!` macro, which should make this eaier to
understand.
This PR also supports custom quoting spans in custom quote macros (e.g.
the `quote` crate). All span quoting goes through the
`proc_macro::quote_span` method, which can be called by a custom quote
macro to perform span quoting. An example of this usage is provided in
`src/test/ui/proc-macro/auxiliary/custom-quote.rs`
Custom quoting currently has a few limitations:
In order to quote a span, we need to generate a call to
`proc_macro::Span::recover_proc_macro_span`. However, proc-macros
support renaming the `proc_macro` crate, so we can't simply hardcode
this path. Previously, the `quote_span` method used the path
`crate::Span` - however, this only works when it is called by the
builtin `quote!` macro in the same crate. To support being called from
arbitrary crates, we need access to the name of the `proc_macro` crate
to generate a path. This PR adds an additional argument to `quote_span`
to specify the name of the `proc_macro` crate. Howver, this feels kind
of hacky, and we may want to change this before stabilizing anything
quote-related.
Additionally, using `quote_span` currently requires enabling the
`proc_macro_internals` feature. The builtin `quote!` macro
has an `#[allow_internal_unstable]` attribute, but this won't work for
custom quote implementations. This will likely require some additional
tricks to apply `allow_internal_unstable` to the span of
`proc_macro::Span::recover_proc_macro_span`.
Parse unsupported "default field const values":
```rust
struct S {
field: Type = const_val,
}
```
Recover from small `:` typo and provide suggestion:
```rust
struct S {
field; Type,
field2= Type,
}
```
Use .name_str() to format primitive types in error messages
This pull request fixes#84976. The problem described there is caused by this code
506e75cbf8/compiler/rustc_middle/src/ty/error.rs (L161-L166)
using `Debug` formatting (`{:?}`), while the proper solution is to call `name_str()` of `ty::IntTy`, `ty::UintTy` and `ty::FloatTy`, respectively.
Change param name (k to key and v to value) in std::env module
1. When I was reading code the ide displayed `k` and `v`, so I
thought it would be better to show key and value?
2. I noticed var method already uses `key` instead of `k` so it
is more consistent to use `key` instead of `k`?
Thanks
rustdoc: remove explicit boolean comparisons.
For boolean variables it's shorter and more readable to check the value directly, or negate it with `!`.
In a couple of cases I reordered an if/else pair because it made the initial `if` statement simpler.
An example of a style guide recommending this: https://airbnb.io/javascript/#comparison--shortcuts
r? `@GuillaumeGomez`
In rustdoc's main.js, we had an onclick handler for the whole document
that would dispatch to handlers for various elements. This change
attaches the handlers to the elements that trigger them, instead.
This simplfies the code and avoids reimplementing the browser's bubbling
functionality.
As part of this change, change from a class to an id for help button.
Move the handlers and associated code for highlighting source lines into
source-script.js (and factor out a shared regex).
BTree: no longer copy keys and values before dropping them
When dropping BTreeMap or BTreeSet instances, keys-value pairs are up to now each copied and then dropped, at least according to source code. This is because the code for dropping and for iterators is shared.
This PR postpones the treatment of doomed key-value pairs from the intermediate functions `deallocating_next`(`_back`) to the last minute, so the we can drop the keys and values in place. According to the library/alloc benchmarks, this does make a difference, (and a positive difference with an `#[inline]` on `drop_key_val`). It does not change anything for #81444 though.
r? `@Mark-Simulacrum`
For boolean variables it's shorter and more readable to check the value
directly, or negate it with `!`.
In a couple of cases I reordered an if/else pair because it made the
initial `if` statement simpler.
Removed unused isType parameter from two functions.
At first you might think "why not just click through to the aliased
type?", but if a type alias instantiates all of the generic parameters
of the aliased type, then it can show layout info even though the
aliased type cannot (because we can't compute the layout of a generic
type). So I think it's still useful to show layout info for type
aliases.
