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.
Introduce macro sub-namespaces and `macro_use` prelude
This PR implements two mechanisms needed for correct macro name resolution: macro sub-namespace and `macro_use` prelude.
- [macro sub-namespaces][subns-ref]
Macros have two sub-namespaces: one for function-like macro and the other for those in attributes (including custom derive macros). When we're resolving a macro name for function-like macro, we should ignore non-function-like macros, and vice versa.
This helps resolve single-segment macro names because we can (and should, as rustc does) fallback to names in preludes when the name in the current module scope is in different sub-namespace.
- [`macro_use` prelude][prelude-ref]
`#[macro_use]`'d extern crate declarations (including the standard library) bring their macros into scope, but they should not be prioritized over local macros (those defined in place and those explicitly imported).
We have been bringing them into legacy (textual) macro scope, which has the highest precedence in name resolution. This PR introduces the `macro_use` prelude in crate-level `DefMap`s, whose precedence is lower than local macros but higher than the standard library prelude.
The first 3 commits are drive-by fixes/refactors.
Fixes#8828 (prelude)
Fixes#12505 (prelude)
Fixes#12734 (prelude)
Fixes#13683 (prelude)
Fixes#13821 (prelude)
Fixes#13974 (prelude)
Fixes#14254 (namespace)
[subns-ref]: https://doc.rust-lang.org/reference/names/namespaces.html#sub-namespaces
[prelude-ref]: https://doc.rust-lang.org/reference/names/preludes.html#macro_use-prelude
Refactor symbol index
Closes https://github.com/rust-lang/rust-analyzer/issues/14677
instead of eagerly fetching the source data in symbol index we do it lazily now, this shouldn't make it much more expensive as we had to parse the source most of the time anyways even after fetching.
fix: ide: exclude sized in go-to actions in hover
fixes#13163
i opted to just simply omit `Sized` entirely from go-to actions, as opposed to including it if even someone writes an explicit `T: Sized`, as i think a go-to on Sized is of dubious value practically.
Fix explicit deref problems in closure capture
fix the `need-mut` part of #14562
Perhaps surprisingly, it wasn't unique immutable borrow. The code still doesn't emit any of them, and I think those won't happen in edition 2021 (which is currently the only thing implemented), since we always capture `&mut *x` instead of `&mut x`. But I'm not very sure about it.
Add doc-alias based completion
Closes#14406.
I adapted the parsing code from the CfgExpr parsing code, maybe there's a better abstraction for both, or attribute parsing in general. It also includes `doc(hidden)`-parsing, which means it could replace the other function.
There are a few tests for parsing.
`process_all_names` changed the most, I added some docs there to explain what happens.
Many call sites just pass an empy vec to `add_path_resolution`'s `doc_aliases`, since either it doesn't make sense to pass anything (e.g. visibility completion) or I don't know where to get them from. Shouldn't really matter, as it will just not show aliases if the vec is empty and we can extend alias completion in these cases later.
I added two tests in `special.rs` for struct name completion (which was the main thing I wanted). I also tried function and field names, but these don't work yet. I want to add those in a follow-up PR.
internal: add `as_slice` to `hir::Type`
~`remove_slice`~ `as_slice` is same as `remove_ref` but for slices.
Though there is `as_array` which I believe was named such because it also gets the length of the array, maybe. I am still shaky on the names feel free to suggest corrections.
internal: Rename `hir::diagnostics::MissingMatchArms.match_expr` field
`hir::diagnostics::MissingMatchArms.match_expr` had confusing name: it is pointing to scrutinee expression. Renamed to `scrutinee_expr` and used better fitting type for it.
Also small refactorings/cleanup.
MIR episode 2
This PR adds:
1. `need-mut` and `unused-mut` diagnostics
2. `View mir` command which shows MIR for the body under cursor, useful for debugging
3. MIR lowering for or-patterns and for-loops
Handle trait alias definitions
Part of #2773
This PR adds a bunch of structs and enum variants for trait aliases. Trait aliases should be handled as an independent item because they are semantically distinct from traits.
I basically started by adding `TraitAlias{Id, Loc}` to `hir_def::item_tree` and iterated adding necessary stuffs until compiler stopped complaining what's missing. Let me know if there's still anything I need to add.
I'm opening up this PR for early review and stuff. I'm planning to add tests for IDE functionalities in this PR, but not type-related support, for which I put FIXME notes.
Fix associated item visibility in block-local impls
Fixes#14046
When we're resolving visibility of block-local items...
> `self` normally refers to the containing non-block module, and `super` to its parent (etc.). However, visibilities must only refer to a module in the DefMap they're written in, so we restrict them when that happens. ([link])
...unless we're resolving visibility of associated items in block-local impls, because that impl is semantically "hoisted" to the nearest (non-block) module. With this PR, we skip the adjustment for such items.
Since visibility representation of those items is modified, this PR also adjusts visibility rendering in `HirDisplay`.
[link]: a6603fc21d/crates/hir-def/src/nameres/path_resolution.rs (L101-L103)
Fix: Run doctests for structs with lifetime parameters from IDE
Fixes#14142: Doctests can't be triggered for structs with lifetimes
This MR adds lifetime parameters to the structs path for runnables so that they can be triggered from an IDE as well.
This is my first MR for rust-analyzer, please let me know if I should change something, either in code or the description here.
Beginning of MIR
This pull request introduces the initial implementation of MIR lowering and interpreting in Rust Analyzer.
The implementation of MIR has potential to bring several benefits:
- Executing a unit test without compiling it: This is my main goal. It can be useful for quickly testing code changes and print-debugging unit tests without the need for a full compilation (ideally in almost zero time, similar to languages like python and js). There is a probability that it goes nowhere, it might become slower than rustc, or it might need some unreasonable amount of memory, or we may fail to support a common pattern/function that make it unusable for most of the codes.
- Constant evaluation: MIR allows for easier and more correct constant evaluation, on par with rustc. If r-a wants to fully support the type system, it needs full const eval, which means arbitrary code execution, which needs MIR or something similar.
- Supporting more diagnostics: MIR can be used to detect errors, most famously borrow checker and lifetime errors, but also mutability errors and uninitialized variables, which can be difficult/impossible to detect in HIR.
- Lowering closures: With MIR we can find out closure capture modes, which is useful in detecting if a closure implements the `FnMut` or `Fn` traits, and calculating its size and data layout.
But the current PR implements no diagnostics and doesn't support closures. About const eval, I removed the old const eval code and it now uses the mir interpreter. Everything that is supported in stable rustc is either implemented or is super easy to implement. About interpreting unit tests, I added an experimental config, disabled by default, that shows a `pass` or `fail` on hover of unit tests (ideally it should be a button similar to `Run test` button, but I didn't figured out how to add them). Currently, no real world test works, due to missing features including closures, heap allocation, `dyn Trait` and ... so at this point it is only useful for me selecting what to implement next.
The implementation of MIR is based on the design of rustc, the data structures are almost copy paste (so it should be easy to migrate it to a possible future stable-mir), but the lowering and interpreting code is from me.
add: clean api to get `raw_ptr` type
There doesn't seem to be an API to fetch the type of `raw_ptr`, which is helpful for a project I work on.
Notes:
- I am unsure about the function name, do let me know if I should use something else.
- Also unsure about where to add tests, for hir changes. Will fix it as needed.
fix:add a case in which remainig is None in resolveing types when resolving hir path.
fix#14030 The variable type is being determined incorrectly
This PR fixed a problem in which `go to definition` is jumping to the incorrect position because it was failing to resolve the type in case it defined in the module when resolving hir.
In addition, I added a test for this issue and refactored the related code.
This is my first PR and I am using a translation tool to write this text. Let me know if you have any problems.
Support generic function in `generate_function` assist
Part of #3639
This PR adds support for generic function generation in `generate_function` assist. Now the assist looks for generic parameters and trait bounds in scope, filters out irrelevant ones, and generates new function with them.
See `fn_generic_params()` for the outline of the procedure, and see comments on `filter_unnecessary_bounds()` for criteria for filtering. I think it's good criteria for most cases, but I'm open to opinions and suggestions.
The diff is pretty big, but it should run in linear time w.r.t. the number of nodes we operate on and should be fast enough.
Some notes:
- When we generate function in an existing impl, generic parameters may cause name conflict. While we can detect the conflict and rename conflicting params, I didn't find it worthwhile mainly because it's really easy to resolve on IDE: use Rename functionality.
- I've implemented graph structure myself, because we don't have graph library as a dependency and we only need the simplest one.
- Although `petgraph` is in our dependency graph and I was initially looking to use it, we don't actually depend on it AFAICT since it's only used in chalk's specialization graph handling, which we don't use. I'd be happy to replace my implementation with `petgraph` if it's okay to use it though.
- There are some caveats that I consider out of scope of this PR. See FIXME notes on added tests.
