move test that shouldn't be in test/run-pass/
We no longer test `src/test/run-pass/`; the proper way now is `// run-pass` in `src/test/ui/`
r? @petrochenkov
handle elision in async fn correctly
We now always make fresh lifetimne parameters for all elided
lifetimes, whether they are in the inputs or outputs. But then
we generate `'_` in the case of elided lifetimes from the outputs.
Example:
```rust
async fn foo<'a>(x: &'a u32) -> &u32 { .. }
```
becomes
```rust
type Foo<'a, 'b> = impl Future<Output = &'b u32>;
fn foo<'a>(x: &'a u32) -> Foo<'a, '_>
```
Fixes#63388
syntax: account for CVarArgs being in the argument list.
Fixes#63430 by testing for `1` argument (the `CVarArgs` itself) instead of `0`.
Note that the error has basically been impossible to trigger since the change that caused #63430, so perhaps we need an audit of untested errors.
Also, this check probably belongs in AST validation/HIR lowering, but I'd rather fix it in place for now.
r? @petrochenkov cc @dlrobertson
When encountering a boxed value as expected and a stack allocated value
that could be boxed to fulfill the expectation, like in the following
snippet, suggest `Box::new` wrapping.
We now always make fresh lifetimne parameters for all elided
lifetimes, whether they are in the inputs or outputs. But then
we generate `'_` in the case of elided lifetimes from the outputs.
Example:
```rust
async fn foo<'a>(x: &'a u32) -> &u32 { .. }
```
becomes
```rust
type Foo<'a, 'b> = impl Future<Output = &'b u32>;
fn foo<'a>(x: &'a u32) -> Foo<'a, '_>
```
This commit prohibits return position `impl Trait` types that "inherit
lifetimes" from the parent scope. The intent is to forbid cases that are
challenging until they can be addressed properly.
Improve invalid_value lint message
The lint now explains which type is involved and why it cannot be initialized this way. It also points at the innermost struct/enum field that has an offending type, if any.
See https://github.com/erlepereira/x11-rs/issues/99#issuecomment-520311911 for how this helps in some real-world code hitting this lint.
Suggest using a qualified path in patterns with inconsistent bindings
A program like the following one:
```rust
enum E { A, B, C }
fn f(x: E) -> bool {
match x {
A | B => false,
C => true
}
}
```
is rejected by the compiler due to `E` variant paths not being in scope.
In this case `A`, `B` are resolved as pattern bindings and consequently
the pattern is considered invalid as the inner or-patterns do not bind
to the same set of identifiers.
This is expected but the compiler errors that follow could be surprising
or confusing to some users. This commit adds a help note explaining that
if the user desired to match against variants or consts, they should use
a qualified path. The help note is restricted to cases where the identifier
starts with an upper-case sequence so as to reduce the false negatives.
Since this happens during resolution, there's no clean way to check what
it is the patterns match against. The syntactic criterium, however, is in line
with the convention that's assumed by the `non-camel-case-types` lint.
Fixes#50831.