Implement diagnostics in all places left: generics (predicates, defaults, const params' types), fields, and type aliases.
Unfortunately this results in a 20mb addition in `analysis-stats .` due to many type methods returning an addition diagnostics result now (even if it's `None` in most cases). I'm not sure if this can be improved.
An alternative strategy that can prevent the memory usage growth is to never produce diagnostics in hir-ty methods. Instead, lower all types in the hir crate when computing diagnostics from scratch (with diagnostics this time). But this has two serious disadvantages:
1. This can cause code duplication (although it can probably be not that bad, it will still mean a lot more code).
2. I believe we eventually want to compute diagnostics for the *entire* workspace (either on-type or on-save or something alike), so users can know when they have diagnostics even in inactive files. Choosing this approach will mean we lose all precomputed salsa queries. For one file this is fine, for the whole workspace this will be very slow.
The diagnostic implemented is a simple one (E0109). It serves as a test for the new foundation.
This commit only implements diagnostics for type in bodies and body-carrying signatures; the next commit will include diagnostics in the rest of the things.
Also fix one weird bug that was detected when implementing this that caused `Fn::(A, B) -> C` (which is a valid, if bizarre, alternative syntax to `Fn(A, B) -> C` to lower incorrectly.
And also fix a maybe-bug where parentheses were sneaked into a code string needlessly; this was not detected until now because the parentheses were removed (by the make-AST family API), but with a change in this commit they are now inserted. So fix that too.
Most paths are types and therefore already are in the source map, but the trait in impl trait and in bounds are not.
We do this by storing them basically as `TypeRef`s. For convenience, I created a wrapper around `TypeRefId` called `PathId` that always stores a path, and implemented indexing from the types map to it.
Fortunately, this change impacts memory usage negligibly (adds 2mb to `analysis-stats .`, but that could be just fluff). Probably because there aren't that many trait bounds and impl traits, and this also shrinks `TypeBound` by 8 bytes.
I also added an accessor to `TypesSourceMap` to get the source code, which will be needed for diagnostics.
We add union fields access (in both expressions and patterns) and inline assembly.
That completes the unsafe check (there are some other unsafe things but they are unstable), and so also opens the door to reporting unused unsafe without annoying people about their not-unused unsafe blocks.
So that given a `TypeRef` we will be able to trace it back to source code.
This is necessary to be able to provide diagnostics for lowering to chalk tys, since the input to that is `TypeRef`.
This means that `TypeRef`s now have an identity, which means storing them in arena and not interning them, which is an unfortunate (but necessary) loss but also a pretty massive change. Luckily, because of the separation layer we have for IDE and HIR, this change never crosses the IDE boundary.
And few more fixups.
I was worried this will lead to more memory usage since `ExprOrPatId` is double the size of `ExprId`, but this does not regress `analysis-stats .`. If this turns out to be a problem, we can easily use the high bit to encode this information.
fix: Get rid of `$crate` in expansions shown to the user
Be it "Expand Macro Recursively", "Inline macro" or few other things.
We replace it with the crate name, as should've always been.
Probably fixes some issues, but I don't know what they are.
fix: Fix `inline_const_as_literal` error when the number >= 10
## Description
### The Bug
This PR fixes a small bug in the IDE assistence (`inline_const_as_literal`). When the being-inlined constant is a number and it is greater than or equal to 10, the assistence inserts unexpected string `(0x...)` after the number itself. A simple example is followed:
Current `inline_const_as_literal` changes
```rs
const A: usize = 16;
fn f() -> usize {
A // inline the constant
}
```
into
```rs
const A: usize = 16;
fn f() -> usize {
16 (0x10)
}
```
The bug originates from #14925 & #15306 . #14925 added some unittests, but it just tested the number-inlining behavior when the number is `0`.
50882fbfa2/crates/ide-assists/src/handlers/inline_const_as_literal.rs (L124-L138)
And #15306 modified the behavior of `Const::render_eval` and added the `(0x...)` part after the number (if the number >= `10`). Because of insufficient unittests in #14925, changes about `Const::render_eval` in #15306 introduced this bug with no CI failure.
### The Fix
I think `Const::render_eval` is intended for user-facing value displaying (e.g. hover) and not designed for `inline_const_as_literal`. To fix the bug, I defined a new function named `Const::eval`, which evaluates the value itself faithfully and simply and does nothing else.
## Thanks
Thanks `@roife` for your kind help. Your guidance helped me better understand the code.
internal: Lay basic ground work for standalone mbe tests
Most of our mbe hir-def tests don't actually do anything name res relevant, we can (and should) move those down the stack into `mbe/hir-expand`.
This PR touches a lot of parts. But the main changes are changing
`hir_expand::Name` to be raw edition-dependently and only when necessary
(unrelated to how the user originally wrote the identifier),
and changing `is_keyword()` and `is_raw_identifier()` to be edition-aware
(this was done in #17896, but the FIXMEs were fixed here).
It is possible that I missed some cases, but most IDE parts should properly
escape (or not escape) identifiers now.
The rules of thumb are:
- If we show the identifier to the user, its rawness should be determined
by the edition of the edited crate. This is nice for IDE features,
but really important for changes we insert to the source code.
- For tests, I chose `Edition::CURRENT` (so we only have to (maybe) update
tests when an edition becomes stable, to avoid churn).
- For debugging tools (helper methods and logs), I used `Edition::LATEST`.
