Automatically instaciate trivially instaciable structs in "Generate new" and "Fill struct fields"
As proposed in #12535 this PR changes the "Generate new" and "Fill struct fields" assist/diagnostic to instanciate structs with no fields and enums with a single empty variant.
For example:
```rust
pub enum Bar {
Bar {},
}
struct Foo<T> {
a: usize,
bar: Bar,
_phantom: std::marker::PhantomData<T>,
}
impl<T> Foo<T> {
/* generate new */
fn random() -> Self {
Self { /* Fill struct fields */ }
}
}
```
was previously:
```rust
impl<T> Foo<T> {
fn new(a: usize, bar: Bar, _phantom: std::marker::PhantomData<T>) -> Self {
Self { a, bar, _phantom }
}
fn random() -> Self {
Self {
a: todo!(),
bar: todo!(),
_phantom: todo!(),
}
}
}
```
and is now:
```rust
impl<T> Foo<T> {
fn new(a: usize) -> Self {
Self {
a,
bar: Bar::Bar {},
_phantom: std::marker::PhantomData
}
}
fn random() -> Self {
Self {
a: todo!(),
bar: Bar::Bar {},
_phantom: std::marker::PhantomData,
}
}
}
```
I'd be happy about any suggestions.
## TODO
- [x] deduplicate `use_trivial_constructor` (unclear how to do as it's used in two separate crates)
- [x] write tests
Closes#12535
fix: Support generics in extract_function assist
This change attempts to resolve issue #7636: Extract into Function does not
create a generic function with constraints when extracting generic code.
In `FunctionBody::analyze_container`, we now traverse the `ancestors` in search
of `AnyHasGenericParams`, and attach any `GenericParamList`s and `WhereClause`s
we find to the `ContainerInfo`.
Later, in `format_function`, we collect all the `GenericParam`s and
`WherePred`s from the container, and filter them to keep only types matching
`TypeParam`s used within the newly extracted function body or param list. We
can then include the new `GenericParamList` and `WhereClause` in the new
function definition.
This change only impacts `TypeParam`s. `LifetimeParam`s and `ConstParam`s are
out of scope for this change.
I've never contributed to this project before, but I did try to follow the style guide. I believe that this change represents an improvement over the status quo, but I think it's also fair to argue that it doesn't fully "fix" the linked issue. I'm totally open to merging this as is, or going further to try to make a more complete solution. Also: if there are other unit or integration tests I should add, please let me know where to look!
This change attempts to resolve issue #7636: Extract into Function does not
create a generic function with constraints when extracting generic code.
In `FunctionBody::analyze_container`, we now traverse the `ancestors` in search
of `AnyHasGenericParams`, and attach any `GenericParamList`s and `WhereClause`s
we find to the `ContainerInfo`.
Later, in `format_function`, we collect all the `GenericParam`s and
`WherePred`s from the container, and filter them to keep only types matching
`TypeParam`s used within the newly extracted function body or param list. We
can then include the new `GenericParamList` and `WhereClause` in the new
function definition.
This change only impacts `TypeParam`s. `LifetimeParam`s and `ConstParam`s are
out of scope for this change.
When extracting a field expression, if RA was unable to resolve the type of the
field, we would previously fall back to using "var_name" as the variable name.
Now, when the `Expr` being extracted matches a `FieldExpr`, we can use the
`NameRef`'s ident token as a fallback option.
fixes#10035
This change fixes#12705.
In `FunctionBody::analyze`, we need to search any `ClosureExpr`s we encounter
for any `NameRef`s, to ensure they aren't missed.
fix: Extract function from trait impl
This change fixes#10036, "Extract to function assist implements nonexistent
trait methods".
When we detect that the extraction is coming from within a trait impl, and that
a `self` param will be necessary, we adjust which `SyntaxNode` to `insert_after`,
and create a new empty `impl` block for the newly extracted function.
This change fixes#10036, "Extract to function assist implements nonexistent
trait methods".
When we detect that the extraction is coming from within a trait impl, and that
a `self` param will be necessary, we adjust which `SyntaxNode` to `insert_after`,
and create a new empty `impl` block for the newly extracted function.
This change fixes issue #10037, in more or less the most naive fashion
possible.
We continue to start with the hardcoded default of "fun_name", and now append a
counter to the end of it if that name is already in scope.
In the future, we can probably apply more heuristics here to wind up with more
useful names by default, but for now this resolves the immediate problem.
Order auto-imports by relevance
Fixes#10337.
Basically we sort the imports according to how "far away" the imported item is from where we want to import it to. This change makes it so that imports from the current crate are sorted before any third-party crates. Additionally, we make an exception for builtin crates (`std`, `core`, etc.) so that they are sorted before any third-party crates.
There are probably other heuristics that should be added to improve the experience (such as preferring imports that are common elsewhere in the same crate, and ranking crates depending on the dependency graph). However, I think this is a first good step.
PS. This is my first time contributing here, so please be gentle if I have missed something obvious :-)
The selected imports have to have a common prefix in paths.
Before
```rust
$0use std::fmt::Display;
use std::fmt::Debug;$0
```
After
```rust
use std::fmt::{Display, Debug};
```
fix(extract_module) resolving import panics and improve import resolution
- Should solve #11766
- While adding a test case for this issue, I observed another issue:
For this test case:
```rust
mod x {
pub struct Foo;
pub struct Bar;
}
use x::{Bar, Foo};
$0type A = (Foo, Bar);$0
```
extract module should yield this:
```rust
mod x {
pub struct Foo;
pub struct Bar;
}
use x::{};
mod modname {
use super:❌:Bar;
use super:❌:Foo;
pub(crate) type A = (Foo, Bar);
}
```
instead it gave:
```rust
mod x {
pub struct Foo;
pub struct Bar;
}
use x::{};
mod modname {
use x::Bar;
use x::Foo;
pub(crate) type A = (Foo, Bar);
}
```
So fixed this problem with second commit
