MIR episode 5
This PR inits drop support (it is very broken at this stage, some things are dropped multiple time, drop scopes are wrong, ...) and adds stdout support (`println!` doesn't work since its expansion is dummy, but `stdout().write(b"hello world\n")` works if you use `RA_SYSROOT_HACK`) for interpreting. There is no useful unit test that it can interpret yet, but it is a good sign that it didn't hit a major road block yet.
In MIR lowering, it adds support for slice pattern and anonymous const blocks, and some fixes so that we can evaluate `SmolStr::new_inline` in const eval. With these changes, 57 failed mir body remains.
fix: Force disable augmentsSyntaxTokens capability on VSCode
The default textmate grammar for rust in VSCode is pretty brittle, quite often coloring things very differently than we'd like to so we force full semantic highlighting by disabling that config.
fix: Diagnose non-value return and break type mismatches
Could definitely deserve more polished diagnostics, but this at least brings the message across for now.
fix(analysis-stats): divided by zero error
## What does this PR try to resolve?
2023-05-15 rust-analyzer suffers from
```
thread 'main' panicked at 'attempt to divide by zero', crates/rust-analyzer/src/cli/analysis_stats.rs:230:56
```
This commit <51e8b8ff14> might be the culprit.
This PR uses `percentage` function to avoid the classic “division by zero” bug.
## Reproducer
```console
cargo new ra-test
pushd ra-test
echo "pub type Foo = u32;" >> src/lib.rs
rust-analyzer analysis-stats .
```
Support `#[macro_use(name, ...)]`
This PR adds support for another form of the `macro_use` attribute: `#[macro_use(name, ...)]` ([reference]).
Note that this form of the attribute is only applicable to extern crate decls, not to mod decls.
[reference]: https://doc.rust-lang.org/reference/macros-by-example.html#the-macro_use-attribute
Parse associated return type bounds
This PR implements parser support for associated return type bounds: `T: Foo<bar(): Send>`. This PR does not implement associated return types (`T::bar(): Send`) because it's not implemented even in rustc, and also removes `(..)`-style return type notation because it has been removed in rust-lang/rust#110203 (effectively reverting #14465).
I don't plan to proactively follow this unstable feature unless an RFC is accepted and my main motivation here is to remove no-longer-valid syntax `(..)` from our parser, nevertheless adding minimal parser support so anyone interested (as can be seen in #14465) can experiment it without rust-analyzer's syntax errors.
Expand more single ident macro calls upon item collection
Addresses https://github.com/rust-lang/rust-analyzer/pull/14781#issuecomment-1546201022
I believe this (almost) brings the number of unresolved names back to pre-#14781:
|r-a version|`analysis-stats compiler/rustc` (rust-lang/rust@69fef92ab2) |
|---|---|
|pre-#14781 (b069eb720b) | exprs: 2747778, ??ty: 122236 (4%), ?ty: 107826 (3%), !ty: 728 |
| #14781 (a7944a93a1) | exprs: 2713080, ??ty: 139651 (5%), ?ty: 114444 (4%), !ty: 730 |
| with this fix | exprs: 2747871, ??ty: 122237 (4%), ?ty: 108171 (3%), !ty: 676 |
(I haven't investigated on the increase in some numbers but hopefully not too much of a problem)
This is only a temporary solution. The core problem is that we haven't fully implemented the textual scope of legacy macros. For example, we *have been* failing to resolve `foo` in the following snippet, even before #14781 or after this patch. As noted in a FIXME, we need a way to resolve names in textual scope without eager expansion during item collection.
```rust
//- /main.rs crate:main deps:lib
lib::mk_foo!();
const A: i32 = foo!();
//^^^^^^ unresolved-macro-call
//- /lib.rs crate:lib
#[macro_export]
macro_rules! mk_foo {
() => {
macro_rules! foo { () => { 42 } }
}
}
```
