fix: rewrite code_action `generate_delegate_trait`
I've made substantial enhancements to the "generate delegate trait" code action in rust-analyzer. Here's a summary of the changes:
#### Resolved the "Can’t find CONST_ARG@158..159 in AstIdMap" error
Fix#15804, fix#15968, fix#15108
The issue stemmed from an incorrect application of PathTransform in the original code. Previously, a new 'impl' was generated first and then transformed, causing PathTransform to fail in locating the correct AST node, resulting in an error. I rectified this by performing the transformation before generating the new 'impl' (using make::impl_trait), ensuring a step-by-step transformation of associated items.
#### Rectified generation of `Self` type
`generate_delegate_trait` is unable to properly handle trait with `Self` type.
Let's take the following code as an example:
```rust
trait Trait {
fn f() -> Self;
}
struct B {}
impl Trait for B {
fn f() -> B { B{} }
}
struct S {
b: B,
}
```
Here, if we implement `Trait` for `S`, the type of `f` should be `() -> Self`, i.e. `() -> S`. However we cannot automatically generate a function that constructs `S`.
To ensure that the code action doesn't generate delegate traits for traits with Self types, I add a function named `has_self_type` to handle it.
#### Extended support for generics in structs and fields within this code action
The former version of `generate_delegate_trait` cannot handle structs with generics properly. Here's an example:
```rust
struct B<T> {
a: T
}
trait Trait<T> {
fn f(a: T);
}
impl<T1, T2> Trait<T1> for B<T2> {
fn f(a: T1) -> T2 { self.a }
}
struct A {}
struct S {
b$0 : B<A>,
}
```
The former version will generates improper code:
```rust
impl<T1, T2> Trait<T1, T2> for S {
fn f(&self, a: T1) -> T1 {
<B as Trait<T1, T2>>::f( &self.b , a)
}
}
```
The rewritten version can handle generics properly:
```rust
impl<T1> Trait<T1> for S {
fn f(&self, a: T1) -> T1 {
<B<A> as Trait<T1>>::f(&self.b, a)
}
}
```
See more examples in added unit tests.
I enabled support for generic structs in `generate_delegate_trait` through the following steps (using the code example provided):
1. Initially, to prevent conflicts between the generic parameters in struct `S` and the ones in the impl of `B`, I renamed the generic parameters of `S`.
2. Then, since `B`'s parameters are instantiated within `S`, the original generic parameters of `B` needed removal within `S` (to avoid errors from redundant parameters). An important consideration here arises when Trait and B share parameters in `B`'s impl. In such cases, these shared generic parameters cannot be removed.
3. Next, I addressed the matching of types between `B`'s type in `S` and its type in the impl. Given that some generic parameters in the impl are instantiated in `B`, I replaced these parameters with their instantiated results using PathTransform. For instance, in the example provided, matching `B<A>` and `B<T2>`, where `T2` is instantiated as `A`, I replaced all occurrences of `T2` in the impl with `A` (i.e. apply the instantiated generic arguments to the params).
4. Finally, I performed transformations on each assoc item (also to prevent the initial issue) and handled redundant where clauses.
For a more detailed explanation, please refer to the code and comments. I welcome suggestions and any further questions!
fix: self type replacement in inline-function
Fix#16113, fix#16091
The problem described in this issue actually involves three bugs.
Firstly, when using `ted` to modify the syntax tree, the offset of nodes on the tree changes, which causes the syntax range information from `hir` to become invalid. Therefore, we need to edit the AST after the last usage for `usages_for_locals`.
The second issue is that when inserting nodes, it's necessary to use `clone_subtree` for duplication because the `ted::replace` operation essentially moves a node.
The third issue is that we should use `ancestors_with_macros` instead of `ancestors` to handle impl definition in macros.
I have fixed the three bugs mentioned above and added unit tests.
internal: Migrate assists to the structured snippet API, part 5
Continuing from #15874
Migrates the following assists:
- `extract_variable`
- `generate_function`
- `replace_is_some_with_if_let_some`
- `replace_is_ok_with_if_let_ok`
Don't trim trailing whitespace from doc comments
Don't trim trailing whitespace from doc comments as multiple trailing spaces indicates a hard line break in Markdown.
I'd have liked to add a unit test for `docs_from_attrs`, but couldn't find a reasonable way to get an `&Attrs` object for use in the test.
Fixes#15877.
fix: make callable fields not complete in method access no parens case
Follow up PR for #15879
Fixes the callable field completion appearing in the method access with no parens case.
fix: no code action 'introduce_named_generic' for impl inside types
Fix#15734.
### Changes Made
- Find params in `ancestors` instead of just `parent`
- Added tests (`replace_impl_with_mut` and `replace_impl_inside`)
fix: Correct references from `rust-analyzer.cargo.check` to `rust-analyzer.check`
When reading the manual, I noticed that the documentation referenced configurations that have since been renamed. This PR updates those references to their new names.
fix: assists panic when trying to edit usage inside macro
When we try to make a syntax node mutable inside a macro to edit it, it seems like the edits aren't properly reflected and will cause a panic when trying to make another syntax node mutable.
This PR changes `bool_to_enum` and `promote_local_to_const` to use the original syntax range instead to edit the original file instead of the macro file. I'm not sure how to do it for `inline_call` with the example I mentioned in the issue, so I've left it out for now.
Fixes#15807
internal: Expose whether a channel has been dropped in lsp-server errors
Not the best way to expose this, but this should allow us to give somewhat better errors when the initialization request is malformed, as currently that just results in a channel disconnected error instead of the deserialization error. cc https://github.com/rust-lang/rust-analyzer/issues/15859
fix: Fix out-of-bounds panic in some macros due to unhandled self_ref
Fixes#16200
I don't fully understand these changes, I just applied and tested the changes suggested in #16200 and they seem to fix the issue on both the repro and my original project.
internal: Simplify implementation of apply_document_changes
While reading through the code base, I stumbled across a piece of code that I found hard to read despite its simple purpose. This is my attempt at making the code easier to understand for future readers.
I won't be offended if this is too minor and not worth your time.
While reading through the code base, I stumbled across a piece of code that I found hard to read despite its simple purpose. This is my attempt at making the code easier to understand for future readers.
I won't be offended if this is too minor and not worth your time.
fix: update VSCode rust-panic problem matcher
Corrected the `rust-panic` task problem matcher for the VSCode Extension to match the new panic message pattern.
From:
```
thread 'main' panicked at 'PANIC_MESSAGE', src/main.rs:L:C
```
To:
```
thread 'main' panicked at src/main.rs:L:C:
PANIC_MESSAGE
```
add test case for negative impl
add a small test case to ensure that we don't emit `trait_impl_redundant_assoc_item` diagnostic for negative impl trait
