rustdoc-json: Output target feature information
`#[target_feature]` attributes refer to a target-specific list of features. Enabling certain features can imply enabling other features. Certain features are always enabled on certain targets, since they are required by the target's ABI. Features can also be enabled indirectly based on other compiler flags.
Feature information is ultimately known to `rustc`. Rather than force external tools to track it – which may be wildly impractical due to `-C target-cpu` – have `rustdoc` output `rustc`'s feature data.
This change is motivated by https://github.com/obi1kenobi/cargo-semver-checks/issues/1246, which intends to detect semver hazards caused by `#[target_feature]`.
try-job: aarch64-gnu
try-job: armhf-gnu
try-job: test-various
try-job: x86_64-msvc-1
try-job: i686-msvc-1
try-job: x86_64-mingw-1
try-job: aarch64-apple
Introduce and use specialized `//@ ignore-auxiliary` for test support files instead of using `//@ ignore-test`
### Summary
Add a semantically meaningful directive for ignoring test *auxiliary* files. This is for auxiliary files that *participate* in actual tests but should not be built by `compiletest` (i.e. these files are involved through `mod xxx;` or `include!()` or `#[path = "xxx"]`, etc.).
### Motivation
A specialized directive like `//@ ignore-auxiliary` makes it way easier to audit disabled tests via `//@ ignore-test`.
- These support files cannot use the canonical `auxiliary/` dir because they participate in module resolution or are included, or their relative paths can be important for test intention otherwise.
Follow-up to:
- #139705
- #139783
- #139740
See also discussions in:
- [#t-compiler > Directive name for non-test aux files?](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Directive.20name.20for.20non-test.20aux.20files.3F/with/512773817)
- [#t-compiler > Handling disabled `//@ ignore-test` tests](https://rust-lang.zulipchat.com/#narrow/channel/131828-t-compiler/topic/Handling.20disabled.20.60.2F.2F.40.20ignore-test.60.20tests/with/512005974)
- [#t-compiler/meetings > [steering] 2025-04-11 Dealing with disabled tests](https://rust-lang.zulipchat.com/#narrow/channel/238009-t-compiler.2Fmeetings/topic/.5Bsteering.5D.202025-04-11.20Dealing.20with.20disabled.20tests/with/511717981)
### Remarks on remaining unconditionally disabled tests under `tests/`
After this PR, against commit 79a272c640, only **14** remaining test files are disabled through `//@ ignore-test`:
<details>
<summary>Remaining `//@ ignore-test` files under `tests/`</summary>
```
tests/debuginfo/drop-locations.rs
4://@ ignore-test (broken, see #128971)
tests/rustdoc/macro-document-private-duplicate.rs
1://@ ignore-test (fails spuriously, see issue #89228)
tests/rustdoc/inline_cross/assoc-const-equality.rs
3://@ ignore-test (FIXME: #125092)
tests/ui/match/issue-27021.rs
7://@ ignore-test (#54987)
tests/ui/match/issue-26996.rs
7://@ ignore-test (#54987)
tests/ui/issues/issue-49298.rs
9://@ ignore-test (#54987)
tests/ui/issues/issue-59756.rs
2://@ ignore-test (rustfix needs multiple suggestions)
tests/ui/precondition-checks/write.rs
5://@ ignore-test (unimplemented)
tests/ui/precondition-checks/read.rs
5://@ ignore-test (unimplemented)
tests/ui/precondition-checks/write_bytes.rs
5://@ ignore-test (unimplemented)
tests/ui/explicit-tail-calls/drop-order.rs
2://@ ignore-test: tail calls are not implemented in rustc_codegen_ssa yet, so this causes 🧊
tests/ui/panics/panic-short-backtrace-windows-x86_64.rs
3://@ ignore-test (#92000)
tests/ui/json/json-bom-plus-crlf-multifile-aux.rs
3://@ ignore-test Not a test. Used by other tests
tests/ui/traits/next-solver/object-soundness-requires-generalization.rs
2://@ ignore-test (see #114196)
```
</details>
Of these, most are either **unimplemented**, or **spurious**, or **known-broken**. The outstanding one is `tests/ui/json/json-bom-plus-crlf-multifile-aux.rs` which I did not want to touch in *this* PR -- that aux file has load-bearing BOM and carriage returns and byte offset matters. I think those test files that require special encoding / BOM probably are better off as `run-make` tests. See #139968 for that aux file.
### Review advice
- Best reviewed commit-by-commit.
- The directive name diverged from the most voted `//@ auxiliary` because I think that's easy to confuse with `//@ aux-{crate,dir}`.
r? compiler
This is for files that *participate* in actual tests but should not be
built by `compiletest` (i.e. these files are involved through `mod xxx;`
or `include!()` or `#[path = "xxx"]`, etc.).
A specialized directive like `//@ ignore-auxiliary` makes it way easier
to audit disabled tests via `//@ ignore-test`.
Fix some bootstrap papercuts
... related to jj and my `./build` symlink setup[^1].
I'm not sure if these are good solutions, but they seem to work. See commits for a bit more info.
r? ``@jieyouxu``
[^1]: see #139804
`#[target_feature]` attributes refer to a target-specific list of
features. Enabling certain features can imply enabling other features.
Certain features are always enabled on certain targets, since they are
required by the target's ABI. Features can also be enabled indirectly
based on other compiler flags.
Feature information is ultimately known to `rustc`. Rather than force
external tools to track it -- which may be wildly impractical due to
`-C target-cpu` -- have `rustdoc` output `rustc`'s feature data.
Apparently there are tests that print canonical paths *and* tests which
print non-canonical paths.
An example of the latter is `tests/ui/type_length_limit.rs`.
Fix fixes failures of the following tests when build directory is a
symlink:
- `tests/ui/error-codes/E{0464,0523}.rs`
- `tests/ui/crate-loading/crateresolve{1,2}.rs` (those are the same tests)
compiletest: Make `SUGGESTION` annotations viral
If one of them is expected in a test file, then others should be annotated as well, in the same way as with `HELP`s and `NOTE`s.
This doesn't require much of an additional annotation burden, but simplifies the rules.
r? ```@jieyouxu```
Fix breakage when running compiletest with `--test-args=--edition=2015`
Compiletest has an `--edition` flag to change the default edition tests are run with. Unfortunately no test suite successfully executes when that flag is passed. If the edition is set to something greater than 2015 the breakage is expected, since the test suite currently supports only edition 2015 (Ferrous Systems will open an MCP about fixing that soonish). Surprisingly, the test suite is also broken if `--edition=2015` is passed to compiletest. This PR focuses on fixing the latter.
This PR fixes the two categories of failures happening when `--edition=2015` is passed:
* Some edition-specific tests set their edition through `//@ compile-flags` instead of `//@ edition`. Compiletest doesn't parse the compile flags, so it would see no `//@ edition` and add another `--edition` flag, leading to a rustc error.
* Compiletest would add the edition after `//@ compile-flags`, while some tests depend on flags passed to `//@ compile-flags` being the last flags in the rustc invocation.
Note that for the first category, I opted to manually go and replace all `//@ compile-flags` setting an edition with an explicit `//@ edition`. We could've changed compiletest to instead check whether an edition was set in `//@ compile-flags`, but I thought it was better to enforce a consistent way to set the edition in tests.
I also added the edition to the stamp, so that changing `--edition` results in tests being re-executed.
r? `@jieyouxu`
Introduce a `//@ needs-crate-type` compiletest directive
The `//@ needs-crate-type: $crate_types...` directive takes a comma-separated list of crate types that the target platform must support in order for the test to be run. This allows the test writer to semantically convey that the ignore condition is based on target crate type needs, instead of using a general purpose `//@ ignore-$target` directive (often without comment).
Fixes#132309.
### Example
```rs
//@ needs-crate-type: dylib (ignored on e.g. wasm32-unknown-unknown)
//@ compile-flags: --crate-type=dylib
fn foo() {}
```
### Review advice
- Best reviewed commit-by-commit.
- The impl is not very clean, I briefly attempted to clean up the directive handling but found that more invasive changes are needed, so I'd like to not block on the cleanup for now.
try-job: test-various
try-job: armhf-gnu
compiletest: don't use stringly paths for `compose_and_run`
Eventually I'd like to fully migrate to `camino`'s `{Utf8Path,Utf8PathBuf}` because compiletest assumes UTF-8 paths all over the place, so this is an precursor change to make the migration diff cleaner.
r? `@Kobzol` (or bootstrap/compiler)
compiletest: Trim whitespace from environment variable names
When a test contains a directive like `//@ exec-env: FOO=bar`, compiletest currently includes that leading space in the name of the environment variable, so it is defined as ` FOO` instead of `FOO`.
This is an annoying footgun that is pretty much never intended, especially since most other directives *do* trim whitespace. So let's get rid of it by trimming the environment variable name.
Values remain untrimmed, since there could conceivably be a use-case for values with leading space, but perhaps we'll end up trimming values too in the future.
Recently observed in https://github.com/rust-lang/rust/pull/138603#issuecomment-2783709359.
Fixes#132990.
Supersedes #133148.
---
try-job: test-various
The `//@ needs-crate-type: $crate_types...` directive takes a
comma-separated list of crate types that the target platform must
support in order for the test to be run.
compiletest: Add directive `dont-require-annotations`
for making matching on specific diagnostic kinds non-exhaustive.
E.g. `//@ dont-require-annotations:ERROR`, like in the examples in this PR.
cc https://github.com/rust-lang/rust/pull/139427#issuecomment-2782827583Closes#132647 FYI `@BoxyUwU` since you've wanted this.
r? `@jieyouxu`
compiletest: Remove the `--logfile` flag
This flag is deprecated in libtest (#134283), and there's no evidence in-tree of this flag actually being passed to compiletest.
For detailed information about test results, bootstrap parses JSON output from compiletest instead (#108659).
As part of my experimental work on removing the libtest dependency from compiletest, it's useful to be able to disconnect libtest functionality that isn't needed.
This flag is deprecated in libtest, and there's no evidence in-tree of this
flag actually being passed to compiletest.
(For detailed information about test results, bootstrap parses JSON output from
compiletest instead.)
Currently `compiletest` panics all over the place but doesn't really use
`anyhow` anyway. I'd like to introduce some more principled error
handling and disciplined diagnostic reporting in the near future.
Those that didn't previously preserved kind are now marked as not requiring annotations to keep the previous behavior.
Also, do not lose diagnostics with an empty message.
compiletest: Encapsulate all of the code that touches libtest
Compiletest currently relies on unstable libtest APIs in order to actually execute tests. That's unfortunate, but removing the dependency isn't trivial.
However, we can make a small step towards removing the libtest dependency by encapsulating the libtest interactions into a single dedicated module. That makes it easier to see what parts of libtest are actually used.
---
As a side-effect of moving the `test_opts` function into that dedicated module, this PR also ends up allowing `--fail-fast` to be passed on the command line, instead of requiring an environment variable.
---
There is still (at least) one other aspect of the libtest dependency that this PR does not address, namely the fact that we rely on libtest's output capture (via unstable std APIs) to capture the output that we print during individual tests. I hope to do something about that at some point.
r? jieyouxu
compiletest: Support matching diagnostics on lines below
Using `//~vvv ERROR`.
This is not needed often, but it's easy to support, and it allows to eliminate a class of `error-pattern`s that cannot be eliminated in any other way.
See the diff for the examples of such patterns coming from parser.
Some of them can be matched by `//~ ERROR` or `//~^ ERROR` as well (when the final newline is allowed), but it changes the shape of reported spans, so I chose to keep the spans by using `//~v ERROR`.
