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`
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 incorrectly replacing references in macro invocation in "Convert to named struct" assist
Fixes#15630.
Complements #13647 (same assist but missed this one), #14920 (inverse action assist).
fix: resolve Self type references in delegate method assist
This PR makes the delegate method assist resolve any `Self` type references in the parameters or return type. It also works across macros such as the `uint_impl!` macro used for `saturating_mul` in the issue example.
Closes#14485
internal: Migrate assists to the structured snippet API, part 4
Continuing from #15260
Migrates the following assists:
- `add_turbo_fish`
- `add_type_ascription`
- `destructure_tuple_binding`
- `destructure_tuple_binding_in_subpattern`
I did this a while ago, but forgot to make a PR for the changes until now. 😅
Due to the way the current tree mutation api works, we need to collect
changes before we can apply them to the real syntax tree, and also can only
switch to a file once.
`destructure_tuple_binding_in_sub_pattern` also gets migrated even
though can't be used.
feat: implement tuple return type to tuple struct assist
This PR implements the `convert_tuple_return_type_to_struct` assist, for converting the return type of a function or method from a tuple to a tuple struct. Additionally, it moves the `to_camel_case` and `char_has_case` functions from `case_conv` to `stdx` so that they can be used similar to `to_lower_snake_case`.
[tuple_return_type_to_tuple_struct.webm](https://github.com/rust-lang/rust-analyzer/assets/52933714/2803ff58-fde3-4144-9495-7c7c7e139075)
Currently, the assist puts the struct definition above the function, or above the nearest `impl` or `trait` if applicable and only rewrites literal tuples that are returned in the body of the function. Additionally, it only attempts to rewrite simple tuple pattern usages with the corresponding tuple struct pattern but does so across files and modules.
I think that this is sufficient for the majority of use cases but I could be wrong. One thing I'm still not sure how to approach is handling `Self` and generics/lifetimes in the tuple type to be extracted. I was thinking of either manually figuring out what lifetimes and generics are in scope and using them (sort of similar to the `generate_function` assist) or maybe using `ctx.sema.resolve_type` and `generic_params` on `hir::Type` but this seems to not deal with lifetimes.
Closes#14293
fix: make bool_to_enum assist create enum at top-level
This pr makes the `bool_to_enum` assist create the `enum` at the next closest module block or at top-level, which fixes a few tricky cases such as with an associated `const` in a trait or module:
```rust
trait Foo {
const $0BOOL: bool;
}
impl Foo for usize {
const BOOL: bool = true;
}
fn main() {
if <usize as Foo>::BOOL {
println!("foo");
}
}
```
Which now properly produces:
```rust
#[derive(PartialEq, Eq)]
enum Bool { True, False }
trait Foo {
const BOOL: Bool;
}
impl Foo for usize {
const BOOL: Bool = Bool::True;
}
fn main() {
if <usize as Foo>::BOOL == Bool::True {
println!("foo");
}
}
```
I also think it's a bit nicer, especially for local variables, but didn't really know to do it in the first PR :)
fix: panic with wrapping/unwrapping result return type assists
With the `wrap_return_type_in_result` assist, the following code results in a panic (note the lack of a semicolon):
```rust
fn foo(num: i32) -> $0i32 {
return num
}
=>
thread 'handlers::wrap_return_type_in_result::tests::wrap_return_in_tail_position' panicked at crates/syntax/src/ted.rs:137:41:
called `Option::unwrap()` on a `None` value
```
I think this is because it first walks the body expression to change any `return` expressions and then walks all tail expressions, resulting in the `return num` being changed twice since it is both a `return` and in tail position. This can also happen when a `match` is in tail position and `return` is used in a branch for example. Not really sure how big of an issue this is in practice though since this seems to be the only case that is impacted and can be reduced to just `num` instead of `return num`.
This also occurs with the `unwrap_result_return_type` assist but panics with the following instead:
```
thread 'handlers::unwrap_result_return_type::tests::wrap_return_in_tail_position' panicked at /rustc/3223b0b5e8dadda3f76c3fd1a8d6c5addc09599e/library/alloc/src/string.rs:1766:29:
assertion failed: self.is_char_boundary(n)
```
minor : Deunwrap convert_comment_block and desugar_doc_comment
Closes subtask 13 of #15398 . I still don't know a more idiomatic way for the for loops I added, any suggestion would make me happy.
Although it doesn't panic now, further changes to how we recover from incomplete syntax
may cause this assist to panic. To mitigate this a test case has been added.
feat: Bool to enum assist
This adds the `bool_to_enum` assist, which converts the type of boolean local variables, fields, constants and statics to a new `enum` type, making it easier to distinguish the meaning of `true` and `false` by renaming the variants.
Closes#14779
Field shorthand overwritten in promote local to const assist
Currently, running `promote_local_to_const` on the following:
```rust
struct Foo {
bar: usize,
}
fn main() {
let $0bar = 0;
let foo = Foo { bar };
}
```
Results in:
```rust
struct Foo {
bar: usize,
}
fn main() {
const BAR: usize = 0;
let foo = Foo { BAR };
}
```
But instead should be something like:
```rust
struct Foo {
bar: usize,
}
fn main() {
const BAR: usize = 0;
let foo = Foo { bar: BAR };
}
```
Bind unused parameter assistant
This PR introduces a new **Bind unused parameter assistant**.
While we do have a QuickFix from `rustc` (prefixing the parameter with an underscore), it's sometimes more convenient to suppress the warning using the following approach:
```rust
fn some_function(unused: i32) {}
```
->
```rust
fn some_function(unused: i32) {
let _ = unused;
}
```
minor : Deunwrap generate_derive
#15398 subtask 1. Since the editing closure has arms, I did something *experimental* ( in this case just a clever term for bad code ) to bypass creating an `Option` but I am ready to change this.
the "add missing members" assists: implemented substitution of default values of const params
To achieve this, I've made `hir::ConstParamData` store the default values
internal : rewrite DeMorgan assist
fixes#15239 , #15240 . This PR is a rewrite of the DeMorgan assist that essentially rids of all the string manipulation and modifies syntax trees to apply demorgan on a binary expr. The main reason for the rewrite is that I wanted to use `Expr::needs_parens_in` method to see if the expr on which the assist is applied would still need the parens it had once the parent expression's operator had equal precedence with that of the expression. I used `.clone_(subtree|for_update)` left and right and probably more than I should have, so I would also be happy to hear how I could have prevented redundant cloning.
internal: Turn unresolved proc macro expansions into missing expressions
Reduces the amount of type related errors one gets when proc macro expansion is disabled.
Add ExternCrateDecl to HIR
Adding these doesn't really require much design effort as they represent a single import, unlike use trees which are one item that represent 0 or more imports.
We only resolve to this definition when actually resolving on the name or alias of an `extern crate name as alias` item, not usages yet as that requires far more changes that won't lead anywhere without giving it more thought. Nevertheless the changes slightly improve IDE things, an example being hover on the decl showing the merged doc comments for example.
cc https://github.com/rust-lang/rust-analyzer/issues/14079
Added remove unused imports assist
This resolves the most important part of #5131. I needed to make a couple of cosmetic changes to the search infrastructure to do this.
A few open questions:
* Should imports that don't resolve to anything be considered unused? I figured probably not, but it would be a trivial change to make if we want it.
* Is there a cleaner way to make the edits to the use list?
* Is there a cleaner way to get the list of uses that intersect the current selection?
* Is the performance acceptable? When testing this on itself, it takes a good couple seconds to perform the assist.
* Is there a way to hide the rustc diagnostics that overlap with this functionality?
internal: Defer structured snippet rendering to allow escaping snippet bits
Since we know exactly where snippets are, we can transparently escape snippet bits to the exact text edits that need it, and not have to do it for anything other text edits.
Also will eventually fix#11006 once all assists are migrated. This comes as a side-effect of text edits that don't have snippets get marked as having no insert formatting at all.
Don't provide `add_missing_match_arms` assist when upmapping match arm list failed
Fixes#15310
We shouldn't provide the assist when we fail to find the original match arm list.
Note that this PR will temporarily make the assist not applicable when attribute macro operates on the match expression in question, just like the case in #15310, for most of the current stable toolchain users. This is because the sysroot-abi proc-macro-srv on the current stable [discards] spans for `Group` delimiters in some code paths, which the popular `proc-macro2` crate almost always calls, and it makes the identity of match arm list's brackets lost, leading to the upmapping failure. This has been fixed by #14960, which will land in the next stable, 1.71.
[discards]: 8ede3aae28/src/tools/rust-analyzer/crates/proc-macro-srv/src/abis/abi_sysroot/ra_server.rs (L231)
bugfix : skip doc(hidden) default members
fixes #14957 . I have two questions :
1. I am definitely looking for a more idiomatic way for the things I added in `crates/ide-assists/src/utils.rs`. See `FIXME` in that file.
2. Would it be actually better to change `DefaultMethods` to something like
```rust
enum DefaultMethods {
Only( IgnoreHidden ( bool ) ) ,
None
}
```
instead of adding a boolean to every function that calls `crates/ide-assists/src/utils.rs::filter_assoc_items`
internal: Migrate assists to the structured snippet API, part 3
Continuing from #15231
Migrates the following assists:
- `add_missing_match_arms`
- `fix_visibility`
- `promote_local_to_const`
The `add_missing_match_arms` changes are best reviewed commit-by-commit since they're relatively big changes compared to the rest of the commits.
`clone_for_update` is relatively cheap in comparison, since making a
node require parsing an entire source text
Adds a test to make sure that it doesn't crash when multiple uses are
present.
internal: Migrate more assists to use the structured snippet API
Continuing from #14979
Migrates the following assists:
- `generate_derive`
- `wrap_return_type_in_result`
- `generate_delegate_methods`
As a bonus, `generate_delegate_methods` now generates the function and impl block at the correct indentation 🎉.
