Update deprecation version to 1.42 for Error::description
Error::description is deprecated as of version 1.42, as the commit was
not in the release for 1.41.
Fixes#69751
Use subslice patterns in slice methods
For all of the methods that pick off the first or last element, we can
use subslice patterns to implement them directly, rather than relying on
deeper indexing function calls. At a minimum, this means the generated
code will rely less on inlining for performance, but in some cases it
also optimizes better.
test(pattern): add tests for combinations of pattern features
Reference issue #67311
Tests combinations of the following pattern features:
- bindings_after_at
- or_patterns
- slice_patterns
- box_patterns
r? @Centril
Parse & reject postfix operators after casts
This adds an explicit error messages for when parsing `x as Type[0]` or similar expressions. Our add an extra parse case for parsing any postfix operator (dot, indexing, method calls, await) that triggers directly after parsing `as` expressions.
My friend and I worked on this together, but they're still deciding on a github username and thus I'm submitting this for both of us.
It will immediately error out, but will also provide the rest of the parser with a useful parse tree to deal with.
There's one decision we made in how this produces the parse tree. In the situation `&x as T[0]`, one could imagine this parsing as either `&((x as T)[0])` or `((&x) as T)[0]`. We chose the latter for ease of implementation, and as it seemed the most intuitive.
Feedback welcome! This is our first change to the parser section, and it might be completely horrible.
Fixes#35813.
When encountering an Item in a pat context, point at the item def
```
error[E0308]: mismatched types
--> $DIR/const-in-struct-pat.rs:8:17
|
LL | struct foo;
| ----------- `foo` defined here
...
LL | let Thing { foo } = t;
| ^^^ expected struct `std::string::String`, found struct `foo`
|
= note: `foo` is interpreted as a unit struct, not a new binding
help: you can bind the struct field to a different name
|
LL | let Thing { foo: other_foo } = t;
| ^^^^^^^^^^^^^^
```
```
error[E0308]: mismatched types
--> $DIR/const.rs:14:9
|
LL | const FOO: Foo = Foo{bar: 5};
| ----------------------------- constant defined here
...
LL | FOO => {},
| ^^^
| |
| expected `&Foo`, found struct `Foo`
| `FOO` is interpreted as a constant, not a new binding
| help: use different name to introduce a new binding: `other_foo`
```
Fix#55631, fix#48062, cc #42876.
`delay_span_bug` when codegen cannot select obligation
Fix#69602, introduced in #60126 by letting the compiler continue past
type checking after encountering errors.
