fix: Don't add reference when it isn't needed for the "Extract variable" assist
I.e. don't generate `let var_name = &foo()`. Because it always irritates me when I need to fix that.
Anything that creates a new value don't need a reference. That excludes mostly field accesses and indexing.
I had a thought that we can also not generate a reference for fields and indexing as long as the type is `Copy`, but sometimes people impl `Copy` even when they don't want to copy the values (e.g. a large type), so I didn't do that.
feat: Create an assist to convert closure to freestanding fn
The assist converts all captures to parameters.
Closes#17920.
This was more work than I though, since it has to handle a bunch of edge cases...
Based on #17941. Needs to merge it first.
Add `toggle_async_sugar` assist code action
Implement code action for sugaring and de-sugaring asynchronous functions.
This code action does not import `Future` trait when de-sugaring and does not touch function boby, I guess this can be implemented later if needed. This action also does not take into consideration other bounds because IMO it's usually "let me try to use sugared version here".
Feel free to request changes, that's my first code action implementation 😄Closes#17010
Relates to #16195
Separate into create and apply edit
Rename usages
Hacky name map
Add more tests
Handle non-exhaustive
Add some more TODOs
Private fields
Use todo
Nesting
Improve rest token generation
Cleanup
Doc -> regular comment
Support mut
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
