E.g.
```
trait Trait {
type Item: SomeOtherTrait;
}
```
Note that these don't simply desugar to where clauses; as I understand it, where
clauses have to be proved by the *user* of the trait, but these bounds are proved
by the *implementor*. (Also, where clauses on associated types are unstable.)
Like `Iterator<Item: SomeTrait>`.
This is an unstable feature, but it's used in the standard library e.g. in the
definition of Flatten, so we can't get away with not implementing it :)
3938: fix missing match arm false positive r=flodiebold a=JoshMcguigan
This fixes#3932 by skipping the missing match arm diagnostic in the case any of the match arms don't type check properly against the match expression.
I think this is the appropriate behavior for this diagnostic, since `is_useful` relies on all match arms being well formed, and the case of a malformed match arm should probably be handled by a different diagnostic.
Co-authored-by: Josh Mcguigan <joshmcg88@gmail.com>
3905: add ellipsis field to hir pat record r=matklad a=JoshMcguigan
This PR corrects a `fixme`, adding an `ellipsis` field to the hir `Pat::Record` type. It will also be unlock some useful follow on work for #3894.
Additionally it adds a diagnostic for missing fields in record patterns.
~~Marking as a draft because I don't have any tests, and a small amount of manual testing on my branch from #3894 suggests it might *not* be working. Any thoughts on how I can best test this, or else pointers on where I might be going wrong?~~
Co-authored-by: Josh Mcguigan <joshmcg88@gmail.com>
Chalk now panics if we don't implement these methods and run with CHALK_DEBUG,
so I thought I'd try to implement them 'properly'. Sadly, it seems impossible to
do without transmuting lifetimes somewhere. The problem is that we need a `&dyn
HirDatabase` to get names etc., which we can't just put into TLS. I thought I
could just use `scoped-tls`, but that doesn't support references to unsized
types. So I put the `&dyn` into another struct and put the reference to *that*
into the TLS, but I have to transmute the lifetime to 'static for that to work.
3918: Add support for feature attributes in struct literal r=matklad a=bnjjj
As promised here is the next PR to solve 2 different scenarios with feature flag on struct literal.
close#3870
Co-authored-by: Benjamin Coenen <5719034+bnjjj@users.noreply.github.com>
The big change here is counting binders, not
variables (https://github.com/rust-lang/chalk/pull/360). We have to adapt to the
same scheme for our `Ty::Bound`. It's mostly fine though, even makes some things
more clear.
We treat macro calls as expressions (there's appropriate Into impl),
which causes problem if there's expresison and non-expression macro in
the same node (like in the match arm).
We fix this problem by nesting macor patterns into another node (the
same way we nest path into PathExpr or PathPat). Ideally, we probably
should add a similar nesting for macro expressions, but that needs
some careful thinking about macros in blocks: `{ am_i_expression!() }`.
It improves compile time in `--release` mode quite a bit, it doesn't
really slow things down and, conceptually, it seems closer to what we
want the physical architecture to look like (we don't want to
monomorphise EVERYTHING in a single leaf crate).
3549: Implement env! macro r=matklad a=edwin0cheng
This PR implements `env!` macro by adding following things:
1. Added `additional_outdirs` settings in vscode. (naming to be bikeshed)
2. Added `ExternSourceId` which is a wrapping for SourceRootId but only used in extern sources. It is because `OUT_DIR` is not belonged to any crate and we have to access it behind an `AstDatabase`.
3. This PR does not implement the `OUT_DIR` parsing from `cargo check`. I don't have general design about this, @kiljacken could we reuse some cargo watch code for that ?
~~Block on [#3536]~~
PS: After this PR , we (kind of) completed the `include!(concat!(env!('OUT_DIR'), "foo.rs")` macro call combo. [Exodia Obliterate!](https://www.youtube.com/watch?v=RfqNH3FoGi0)
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
To test whether the receiver type matches for the impl, we unify the given self
type (in this case `HashSet<{unknown}>`) with the self type of the
impl (`HashSet<?0>`), but if the given self type contains Unknowns, they won't
be unified with the variables in those places. So we got a receiver type that
was different from the expected one, and concluded the impl doesn't match.
The fix is slightly hacky; if after the unification, our variables are still
there, we make them fall back to Unknown. This does make some sense though,
since we don't want to 'leak' the variables.
Fixes#3547.
To do this we need to carry around the original resolution a bit, because `Self`
gets resolved to the actual type immediately, but you're not allowed to write
the equivalent type in a projection. (I tried just comparing the projection base
type with the impl self type, but that seemed too dirty.) This is basically how
rustc does it as well.
Fixes#3249.
3494: Implement include macro r=matklad a=edwin0cheng
This PR implement builtin `include` macro.
* It does not support include as expression yet.
* It doesn't consider `env!("OUT_DIR")` yet.
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
3385: Fix#3373 r=matklad a=flodiebold
Basically, we need to allow variables in the caller self type to unify with the
impl's declared self type. That requires some more contortions in the variable
handling. I'm looking forward to (hopefully) handling this in a cleaner way when
we switch to Chalk's types and unification code.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
Basically, we need to allow variables in the caller self type to unify with the
impl's declared self type. That requires some more contortions in the variable
handling. I'm looking forward to (hopefully) handling this in a cleaner way when
we switch to Chalk's types and unification code.
E.g. for `&{ some_string() }` in a context where a `&str` is expected, we
reported a mismatch inside the block. The problem is that we're passing an
expectation of `str` down, but the expectation is more of a hint in this case.
There's a long comment in rustc about this, which I just copied.
Also, fix reported location for type mismatches in macros.
E.g. in `match x { None => ... }`, `None` is a path pattern (resolving to the
option variant), not a binding. To determine this, we need to try to resolve the
name during lowering. This isn't too hard since we already need to resolve names
for macro expansion anyway (though maybe a bit hacky).
Fixes#1618.
This adds some tools helpful when debugging nondeterminism in analysis-stats:
- a `--randomize` option that analyses everything in random order
- a `-vv` option that prints even more detail
Also add a debug log if Chalk fuel is exhausted (which would be a source of
nondeterminism, but didn't happen in my tests).
I found one source of nondeterminism (rust-lang/chalk#331), but there are still
other cases remaining.
3147: Check that impl self type matches up with expected self type in path mode r=matklad a=flodiebold
Fixes#3144.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
2844: Use dummy value for line! and column! macro r=matklad a=edwin0cheng
Use dummy value `0` for line! and column! macro.
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
Basically, `Iterator` is re-exported via several steps, which happened to not be
resolved yet when we got to the prelude import, but since the name resolved to
the reexport from `core::iter` (just to no actual items), we gave up trying to
resolve it further.
Maybe part of the problem is that we can have
`PartialResolvedImport::Unresolved` or `PartialResolvedImport::Indeterminate`
with `None` in all namespaces, and handle them differently.
Fixes#2683.
The `-` turned into a `+` during a refactoring.
The original issue was caused by `Read` resolving wrongly to a trait without
type parameters instead of a struct with one parameter; this only fixes the
crash, not the wrong resolution.
2657: Omit closure parameters in closure type display strings r=flodiebold a=SomeoneToIgnore
Part of https://github.com/rust-analyzer/rust-analyzer/issues/1946
I wonder, should we display the the closure trait (Fn/FnMut/FnOnce) in inlay hints instead of `|...|` at all?
Co-authored-by: Kirill Bulatov <mail4score@gmail.com>
2661: Implement infer await from async function r=flodiebold a=edwin0cheng
This PR is my attempt for trying to add support for infer `.await` expression from an `async` function, by desugaring its return type to `Impl Future<Output=RetType>`.
Note that I don't know it is supposed to desugaring it in that phase, if it is not suitable in current design, just feel free to reject it :)
r=@flodiebold
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
It's not very different, except we can directly use Salsa IDs instead of casting
them. This means we need to refactor the handling of errors to get rid of
UNKNOWN_TRAIT though.
2623: Add support macros in impl blocks r=matklad a=edwin0cheng
This PR add support for macros in impl blocks, which reuse `Expander` for macro expansion.
see also: #2459
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
2592: Add std::ops::Index support for infering r=edwin0cheng a=edwin0cheng
see also #2534
Seem like this can't fix#2534 for this case:
```rust
fn foo3(bar: [usize; 2]) {
let baz = bar[1]; // <--- baz is still unknown ?
println!("{}", baz);
}
```
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
When calling a function, argument-position impl Trait is transparent; same for
return-position impl Trait when inside the function. So in these cases, we need
to represent that type not by `Ty::Opaque`, but by a type variable that can be
unified with whatever flows into there.
2466: Handle partial resolve cases r=matklad a=edwin0cheng
Another try to fix#2443 :
We resolve all imports every time in `DefCollector::collect` loop even it is resolved previously.
This is because other unresolved imports and macros will bring in another `PerNs`, so we can only assume that it has been partially resolved.
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
2484: DynMap r=matklad a=matklad
Implement a `DynMap` a semi-dynamic, semi-static map, which helps to thread heterogeneously typed info in a uniform way. Totally inspired by df3bee3038/compiler/frontend/src/org/jetbrains/kotlin/resolve/BindingContext.java.
@flodiebold wdyt? Seems like a potentially useful pattern for various source-map-like things.
Co-authored-by: Aleksey Kladov <aleksey.kladov@gmail.com>
If we are expecting a `&Foo` and get a `&something`, when checking the
`something`, we are *expecting* a `Foo`, but we shouldn't try to unify whatever
we get with that expectation, because it could actually be a `&Foo`, and `&&Foo`
coerces to `&Foo`. So this fixes quite a few false type mismatches.
The stand-alone `unify` requires that the type doesn't contain any type
variables. So we can't share the code here for now (without more refactoring)...
2465: Extract built-in trait implementations to separate module r=matklad a=flodiebold
This untangles the builtin logic from the Chalk translation.
Co-authored-by: Florian Diebold <flodiebold@gmail.com>
2455: Add BuiltinShadowMode r=flodiebold a=edwin0cheng
This PR try to fix#1905 by introduce an `BuiltinShadowMode` in name resolving functions.
cc @flodiebold
Co-authored-by: Edwin Cheng <edwin0cheng@gmail.com>
