Use `tcx.ty_error_with_guaranteed` in more places, rename variants
1. Use `ty_error_with_guaranteed` more so we don't delay so many span bugs
2. Rename `ty_error_with_guaranteed` to `ty_error`, `ty_error` to `ty_error_misc`. This is to incentivize using the former over the latter in cases where we already are witness to a `ErrorGuaranteed` token.
Second commit is just name replacement, so the first commit can be reviewed on its own with more scrutiny.
Use restricted Damerau-Levenshtein distance for diagnostics
This replaces the existing Levenshtein algorithm with the Damerau-Levenshtein algorithm. This means that "ab" to "ba" is one change (a transposition) instead of two (a deletion and insertion). More specifically, this is a _restricted_ implementation, in that "ca" to "abc" cannot be performed as "ca" → "ac" → "abc", as there is an insertion in the middle of a transposition. I believe that errors like that are sufficiently rare that it's not worth taking into account.
This was first brought up [on IRLO](https://internals.rust-lang.org/t/18227) when it was noticed that the diagnostic for `prinltn!` (transposed L and T) was `print!` and not `println!`. Only a single existing UI test was effected, with the result being an objective improvement.
~~I have left the method name and various other references to the Levenshtein algorithm untouched, as the exact manner in which the edit distance is calculated should not be relevant to the caller.~~
r? ``@estebank``
``@rustbot`` label +A-diagnostics +C-enhancement
NB: Since we are using the same InferCtxt in each iteration,
we essentially *spoil* the inference variables and we only
ever get at most *one* applicable candidate (only the 1st candidate
has clean variables that can still unify correctly).
Deny non-lifetime bound vars in `for<..> ||` closure binders
Moves the check for illegal bound var types from astconv to resolve_bound_vars. If a binder is defined to have a type or const late-bound var that's not allowed, we'll resolve any usages to ty error or const error values, so we shouldn't ever see late-bound types or consts in places they aren't expected.
Fixes#108184Fixes#108181Fixes#108192
Switch to `EarlyBinder` for `type_of` query
Part of the work to finish #105779 and implement https://github.com/rust-lang/types-team/issues/78.
Several queries `X` have a `bound_X` variant that wraps the output in `EarlyBinder`. This adds `EarlyBinder` to the return type of the `type_of` query and removes `bound_type_of`.
r? `@lcnr`
Implement partial support for non-lifetime binders
This implements support for non-lifetime binders. It's pretty useless currently, but I wanted to put this up so the implementation can be discussed.
Specifically, this piggybacks off of the late-bound lifetime collection code in `rustc_hir_typeck::collect::lifetimes`. This seems like a necessary step given the fact we don't resolve late-bound regions until this point, and binders are sometimes merged.
Q: I'm not sure if I should go along this route, or try to modify the earlier nameres code to compute the right bound var indices for type and const binders eagerly... If so, I'll need to rename all these queries to something more appropriate (I've done this for `resolve_lifetime::Region` -> `resolve_lifetime::ResolvedArg`)
cc rust-lang/types-team#81
r? `@ghost`
Optimize `mk_region`
PR #107869 avoiding some interning under `mk_ty` by special-casing `Ty` variants with simple (integer) bodies. This PR does something similar for regions.
r? `@compiler-errors`
Much like there are specialized variants of `mk_ty`. This will enable
some optimization in the next commit.
Also rename the existing `re_error*` functions as `mk_re_error*`, for
consistency.
Implement `deferred_projection_equality` for erica solver
Somewhat of a revival of #96912. When relating projections now emit an `AliasEq` obligation instead of attempting to determine equality of projections that may not be as normalized as possible (i.e. because of lazy norm, or just containing inference variables that prevent us from resolving an impl). Only do this when the new solver is enabled
