This is a documentation-only deprecation for now.
Over time, we can
- warn and then remove on use of unstable environment variables
- warn on use of stable environment variables (no plan to remove due to
compatibility)
Longer term, we expect test runners, like `cargo test`, to provide the
necessary mechanisms for environmental or persistent configuration (e.g.
using cargo config which supports `.cargo/config.toml` as well as
environment variables).
This would include:
- `RUST_TEST_THREADS`
- `RUST_TEST_NOCAPTURE`
- `RUST_TEST_SHUFFLE` (unstable)
- `RUST_TEST_SHUFFLE_SEED` (unstable)
The primary outcomes for this change are
- Reducing the scope of what is expected for custom test harnesses to
implement
- Reduce the mechanisms that test runners, like `cargo test`, are
expected to track when they are being bypassed to protect against
negative interactions, e.g. `RUST_TEST_NOCAPTURE=1` when json output
is being read.
This improves consistency with commonly expected CLI conventions,
avoiding a common stutter people make when running tests (trying what
they expect and then having to check the docs to then user whats
accepted).
An alternative could have been to take a value, like `--capture <value>` (e.g. `pytest` does this).
Overall, we're shifting focus for features to custom test harnesses (see #134283).
Most of `pytest`s modes will likely be irrelevant in that situation.
As for the rest, its too early to tell which, if any, may be relevant,
so we're sticking with this small, quality of life improvement.
By deprecating `--nocapture`, we intend that custom test harnesses do
not need to support it for reasons outside of their own compatibility
requirements, much like the deprecation in #134283
I'm punting for now on the naming of `RUST_TEST_NOCAPTURE`.
I feel like T-testing-devex should do a wider look at environment
variables role in lib`test` before evaluating whether to
- Deprecate it in favor of the user passing CLI flags or the test runner
providing its own config
- Deprecate in favor of `RUST_TEST_NO_CAPTURE`
- Deprecate in favor of `RUST_TEST_CAPTURE`
Other CLI flags were evaluated for casing consistency:
- `--logfile` has the same problem but was deprecated in #134283Fixes#133073
Passing a `Result<(), &dyn Any>` to `calc_result` requires awkward code at both
call sites, for no real benefit. It's much easier to just pass the payload as
`Option<&dyn Any>`.
No functional change, except that the owned payload is dropped slightly later.
Error messages are supposed to start with lowercase letters, but a lot
of `io::const_error` messages did not. This fixes them to start with a
lowercase letter.
I did consider adding a const check for this to the macro, but some of
them start with proper nouns that make sense to uppercase them.
See https://doc.rust-lang.org/1.85.0/std/error/trait.Error.html
In [1], most dependencies of `std` and other sysroot crates were marked
private, but this did not happen for `alloc` and `test`. Update these
here, marking public standard library crates as the only non-private
dependencies.
[1]: https://github.com/rust-lang/rust/pull/111076
Use `const_error!` when possible
Replace usages of `io::Error::new(io::ErrorKind::Variant, "constant string")` with `io::const_error!(io::ErrorKind::Variant, "constant string")` to avoid allocations when possible. Additionally, fix `&&str` error messages in SGX and missing/misplaced trailing commas in `const_error!`.
Some miscellaneous edition-related library tweaks
Some library edition tweaks that can be done separately from upgrading the whole standard library to edition 2024 (which is blocked on getting the submodules upgraded, for example)
Update emscripten std tests
This disables a bunch of emscripten tests that test things emscripten doesn't support and re-enables a whole bunch of tests which now work just fine on emscripten.
Tested with `EMCC_CFLAGS="-s MAXIMUM_MEMORY=2GB" ./x.py test library/ --target wasm32-unknown-emscripten`.
rust-lang/testing-devex-team#9 proposed changing the behavior of `--logfile`.
The given reasons were:
(1) Bazel can't programmatically process stdout. This seems like a
limitation in Bazel and we recommend focusing on that. If we look at
the wider Rust ecosystem, Rustc and Cargo don't support any such
mechanism and the Cargo team rejected having one. Expecting this in
libtest when its not supported elsewhere seems too specialized.
(2) Tests that leak out non-programmatic output that intermixes with
programmatic output. We acknowledge this is a problem to be evaluated
but we need to make sure we are stepping back and gathering
requirements, rather than assuming `--logfile` will fit the needs.
Independent of the motive, regarding using or changing `--logfile`
(1) Most ways to do it would be a breaking change, like if we respect
any stable `--format`. As suggested above, we could specialize this to
new `--format` values but that would be confusing for some values to
apply but not others.
(2) Other ways of solving this add new features to lib`test` when we are
instead wanting to limit the feature set it has to minimize the
compatibility surface that has to be maintained and the burden it would
put on third party harnesses which are a focus area. Examples include
`--format compact` or a `--log-format` flag
(3) The existence of `--logfile` dates back quite a ways
(5cc050b265,
rust-lang/rust#2127) and the history gives the
impression this more of slipped through rather than being an intended
feature (see also
https://github.com/rust-lang/rust/pull/82350#discussion_r579732071).
Deprecation would better match to how it has been treated.
By deprecating this, we do not expect custom test harnesses
(rust-lang/testing-devex-team#2) to implement this.
T-testing-devex held an FCP for deprecating in rust-lang/testing-devex-team#9
though according to
[RFC #3455](https://rust-lang.github.io/rfcs/3455-t-test.html),
this is still subject to final approval from T-libs-api.
Clean and enable `rustdoc::unescaped_backticks` for `core/alloc/std/test/proc_macro`
I am not sure if the lint is supposed to be "ready enough" (since it is `allow` by default), but it does catch a couple issues in `core` (`alloc`, `std`, `test` and `proc_macro` are already clean), so I propose making it `warn` in all the crates rendered in the website.
Cc: `@GuillaumeGomez`
Fuchsia status code match arm
Adds a match arm for the Fuchsia status code upon a process abort. An additional change moves the Windows status code down into the match arm itself instead of being defined as a constant elsewhere.
r? tmandry
There are some comments describing multiple subsequent `use` items. When
the big `use` reformatting happens some of these `use` items will be
reordered, possibly moving them away from the comment. With this
additional level of formatting it's not really feasible to have comments
of this type. This commit removes them in various ways:
- merging separate `use` items when appropriate;
- inserting blank lines between the comment and the first `use` item;
- outright deletion (for comments that are relatively low-value);
- adding a separate "top-level" comment.
We also entirely skip formatting for four library files that contain
nothing but `pub use` re-exports, where reordering would be painful.
Most modules have such a blank line, but some don't. Inserting the blank
line makes it clearer that the `//!` comments are describing the entire
module, rather than the `use` declaration(s) that immediately follows.
zkvm: fix run_tests
`zkvm` is single-threaded, similar to `emscripten` and `wasm`. The `cfg` for `zkvm` seems to have been dropped. This PR adds the `cfg` again.
libtest: also measure time in Miri
A long time ago we disabled timekeeping of the default test harness in Miri, as otherwise it would fail to run without `-Zmiri-disable-isolation`. However, since then Miri gained a "fake clock" that lets it present some deterministic notion of time when isolation is enabled.
So we could now let libtest do timekeeping again when running in Miri. That's nice as it can help detect tests that run too long. However it can also be confusing as the results with isolation can be quite different than the real time.
``@rust-lang/miri`` what do you think?
