Have `String` use `SliceIndex` impls from `str`
This PR simplifies the implementation of `Index` and `IndexMut` on `String`, and in the process enables indexing `String` by any user types that implement `SliceIndex<str>`.
Similar to #47832
r? libs
Not sure if this warrants a crater run.
Increase visibility of `join_path` and `split_paths`
Add some crosslinking among `std::env` pages to make it easier to discover `join_paths` and `split_paths`. Also add aliases to help anyone searching for `PATH`.
In the previous code, the success block of `lhs` would jump directly to the
success block of `rhs`. However, `rhs_success_block` could already contain
statements that are specific to the RHS, and the direct goto causes them to be
executed in the LHS success path as well.
This patch therefore creates a fresh block that the LHS and RHS success blocks
can both jump to.
And likewise with `ColorConfig::suggests_using_colors`. They both have a
single call site. And note that `BufWriter::supports_color()` always
returns false, which enables a small bit of constant folding along the
way.
In practice, 'a and 'b and 'c are always the same. This change makes
`UnusedExterns` more like `ArtifactNotification`, which uses a single
lifetime 'a in multiple ways.
I removed it in #121206 because I thought thought it wasn't necessary.
But then I had to add an `emit_stashed_diagnostics` call elsewhere in
rustfmt to avoid the assertion failure (which took two attempts to get
right, #121487 and #121615), and now there's an assertion failure in
clippy as well (https://github.com/rust-lang/rust-clippy/issues/12364).
So this commit just reinstates the call in `DiagCtxtInner::drop`. It
also reverts the rustfmt changes from #121487 and #121615, though it
keeps the tests added for those PRs.
Stashed errors used to be counted as errors, but could then be
cancelled, leading to `ErrorGuaranteed` soundness holes. #120828 changed
that, closing the soundness hole. But it introduced other difficulties
because you sometimes have to account for pending stashed errors when
making decisions about whether errors have occured/will occur and it's
easy to overlook these.
This commit aims for a middle ground.
- Stashed errors (not warnings) are counted immediately as emitted
errors, avoiding the possibility of forgetting to consider them.
- The ability to cancel (or downgrade) stashed errors is eliminated, by
disallowing the use of `steal_diagnostic` with errors, and introducing
the more restrictive methods `try_steal_{modify,replace}_and_emit_err`
that can be used instead.
Other things:
- `DiagnosticBuilder::stash` and `DiagCtxt::stash_diagnostic` now both
return `Option<ErrorGuaranteed>`, which enables the removal of two
`delayed_bug` calls and one `Ty::new_error_with_message` call. This is
possible because we store error guarantees in
`DiagCtxt::stashed_diagnostics`.
- Storing the guarantees also saves us having to maintain a counter.
- Calls to the `stashed_err_count` method are no longer necessary
alongside calls to `has_errors`, which is a nice simplification, and
eliminates two more `span_delayed_bug` calls and one FIXME comment.
- Tests are added for three of the four fixed PRs mentioned below.
- `issue-121108.rs`'s output improved slightly, omitting a non-useful
error message.
Fixes#121451.
Fixes#121477.
Fixes#121504.
Fixes#121508.
This commit:
- Moves the ICE file create/open outside the loop. (Redoing it on every
loop iteration works, but is really weird.)
- Moves the explanatory note emission above the loop, which removes the
need for the `enumerate` call.
- Introduces a `decorate` local.
This gives one extra error message on two tests, but is necessary to fix
bigger problems caused by the cancellation of stashed errors.
(Note: why not just avoid stashing altogether? Because that resulted in
additional output changes.)
This gives one extra error message on one test, but is necessary to fix
bigger problems caused by the cancellation of stashed errors.
(Note: why not just avoid stashing altogether? Because that resulted in
additional output changes.)
Opportunistically resolve regions when processing region outlives obligations
Due to the matching in `TypeOutlives` being structural, we should attempt to opportunistically resolve regions before processing region obligations. Thanks ``@lcnr`` for finding this.
r? lcnr
Use `LitKind::Err` for malformed floats
#121120 changed `StringReader::cook_lexer_literal` to return `LitKind::Err` for malformed integer literals. This commit does the same for float literals, for consistency.
r? ``@fmease``
