Add tests for `-Zunpretty=expanded` ported from stringify's tests
This PR adds a new set of tests for the AST pretty-printer.
Previously, pretty-printer edge cases were tested by way of `stringify!` in [tests/ui/macros/stringify.rs](https://github.com/rust-lang/rust/blob/1.78.0/tests/ui/macros/stringify.rs), such as the tests added by 419b26931b and 527e2eac17.
Those tests will no longer provide effective coverage of the AST pretty-printer after #124141. `Nonterminal` and `TokenKind::Interpolated` are being removed, and a consequence is that `stringify!` will perform token stream pretty printing, instead of AST pretty printing, in all of the `stringify!` cases including $:expr and all other interpolations.
This PR adds 2 new ui tests with `compile-flags: -Zunpretty=expanded`:
- **tests/ui/unpretty/expanded-exhaustive.rs** — this test aims for exhaustive coverage of all the variants of `ExprKind`, `ItemKind`, `PatKind`, `StmtKind`, `TyKind`, and `VisibilityKind`. Some parts could use being fleshed out further, but the current state is roughly on par with what exists in the old stringify-based tests.
- **tests/ui/unpretty/expanded-interpolation.rs** — this test covers tricky macro metavariable edge cases that require the AST pretty printer to synthesize parentheses in order for the printed code to be valid Rust syntax.
r? `@nnethercote`
Rename Unsafe to Safety
Alternative to #124455, which is to just have one Safety enum to use everywhere, this opens the posibility of adding `ast::Safety::Safe` that's useful for unsafe extern blocks.
This leaves us today with:
```rust
enum ast::Safety {
Unsafe(Span),
Default,
// Safe (going to be added for unsafe extern blocks)
}
enum hir::Safety {
Unsafe,
Safe,
}
```
We would convert from `ast::Safety::Default` into the right Safety level according the context.
Migrate `run-make/issue64319` to `rmake` and rename
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
~~I noticed that the Makefile was not listed in `allowed-run-makefiles` in Tidy. Does this mean the test was being ignored?~~ EDIT: No, it was there, just not in its expected alphabetical order.
EDIT2: Perhaps it could be interesting to clean this test visually by looping over the `rustc` calls, like in #125227.
Migrate `run-make/no-cdylib-as-rdylib` to `rmake`
Part of #121876 and the associated [Google Summer of Code project](https://blog.rust-lang.org/2024/05/01/gsoc-2024-selected-projects.html).
> "the test will fail if the cdylib is picked, because it doesn't export any rust symbols"
Is that true? Is there a way to verify?
I suggest maybe extending the test with: (after cleaning the directory)
```rust
rustc()
.input("bar.rs")
.crate_type("cdylib")
.run();
rustc()
.input("foo.rs")
.prefer_dynamic()
.run();
fail();
```
to make sure we're actually testing something here.
internal: Use Swatinem/rust-cache for metrics CI
Current metrics caching uses a base cache action, whereas I think the one we use for general ci works here as well. Saw this while noticing that our metrics CI is broken as it for some reason uses an outdated rust stable? (unsure why that is)
Make crashes dump mir to build dir
Set `-Zdump-mir-dir` for `crashes`-style tests.
Alternatively, we just remove `tests/crashes/124436.rs`, since if the only way to get it to repro is via `-Zdump-mir`, then maybe it's not worth it to fix.
Fixes#125029
