fix(libtest): Deprecate '--logfile' - #134283

epage · 2024-12-13T21:09:12Z

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 libtest 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 (5cc050b, #2127) and the history gives the
impression this more of slipped through rather than being an intended feature (see also
#82350 (comment)). 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, this is still subject to final approval from T-libs-api.

Closes rust-lang/testing-devex-team#9

rustbot · 2024-12-13T21:09:21Z

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Noratrieb · 2024-12-13T22:21:57Z

r? libs-api

rustbot · 2025-01-07T16:57:31Z

Some changes occurred in src/tools/cargo

cc @ehuss

traviscross · 2025-01-07T17:29:42Z

This was discussed in the libs-api call today. People on the call were a bit unclear about the context, the motivation, and the broader plan, so it would help if those things might be clarified. In particular:

The context: What is it that --log-file does now (setting aside the proposed change in behavior in Export machine-readable test results to a file testing-devex-team#9), when was it added, why was it added in the first place, why do people use it, how widely is it used, etc.?
The motivation: Why specifically are we unhappy with the current behavior or existence of --log-file, what do we gain by working toward removing it, and what is the cost of not doing so?
The plan: Would this deprecation be working toward a full removal? If so, what's the proposal for how and when that would be done, how the impact of breaking stability here could be mitigated, etc.? Also, is this part of e.g. some larger plan to e.g. simply the arguments in general and deprecate and remove other things?

Thanks for making the proposal here and for filling in the other details that might help the team to build the context needed to make a decision on this.

epage · 2025-01-07T18:29:12Z

Unsure if it was a formatting / presentation issue but most answers to these questions were in the PR description. Not all answers were included, in part because its hard to predict what all may be relevant and in part because this is the first libtest relevant work from T-testing-devex, making this the test case for how our shared responsibility for it will work.

This post re-formats the PR description around the questions and fills in some of the missing context.

What is it that --log-file does now

It will tee test output to a file using an undocumented, custom textual format

Example of a test run

ok error::rich_formats_validation_error
ok error::suggest_trailing
failed error::app_error
ok error::suggest_trailing_last
ok error::trailing_already_in_use

Example when passing --list

test action::append
test action::count
test action::count_with_default_value_if_present
test action::count_with_default_value_if_value

when was it added, why was it added in the first place

This was added Pre-1.0, see #2127

For the motivation, quoting from #2127

This is a short term fix for #2075.

When ehuss was writing end-user documentation for libtest (#82350), they said at #82350 (comment)

I was reluctant to document the specific format, since I don't know if it is intended to be stable or relied upon. It was added without much detail in #2127, and I'm not sure anyone actually uses it (I haven't seen it used before).

(while the format wasn't specified in that PR, the existence of the flag was)

why do people use it, how widely is it used, etc.?

Back at the time of #82350, ehuss was not aware of people using it. T-testing-devex is also not aware of people using it todqay.

It is difficult to evaluate how widely it is used as logfile is a very generic term to search github-wide. With more narrow searches

In this repo, there are 4 PRs or issues that reference it
On users, I only found
- https://users.rust-lang.org/t/capture-test-output-in-file/122306
- https://users.rust-lang.org/t/where-is-rust-test-log-file-generated/105838/2
On internals, I found no reference to it

Looking over those, I'm not seeing any situation where the person is successful with it, usually from #105424, meaning those posts likely do not represent someone actively using it.

The only desired use cases were

For debugging and scraping (https://users.rust-lang.org/t/capture-test-output-in-file/122306)
Bazel can't programmatically process stdout. They need output to be sent to a file and are blocked on --logfile for libtest doesn't respect --format. #57147

For this teeing use case, the Cargo team has rejected it for now in rust-lang/cargo#14555.

The motivation: Why specifically are we unhappy with the current behavior or existence of --log-file, what do we gain by working toward removing it, and what is the cost of not doing so?

The current format is undocumented, bespoke format with limited data. There are challenges with evolving this format or switching to an alternative. These could be worked through with enough effort but the value seems low while this puts more of a burden on custom test harnesses to support and is a responsibility that would generally belong in a test runner (e.g. cargo test). For context, in past discussions with T-libs-api, the emphasis was on minimizing the scope of libtest and instead putting the focus on new features in first-class custom test harness or in test runners.

By deprecating this,

We feature-freeze the behavior in libtest and make the intent clear to users
Remove the need for custom test harnesses to implement this behavior

The plan: Would this deprecation be working toward a full removal? If so, what's the proposal for how and when that would be done, how the impact of breaking stability here could be mitigated, etc.? Also, is this part of e.g. some larger plan to e.g. simply the arguments in general and deprecate and remove other things?

A full removal was not broached as that would be a breaking change. We had not considered a mitigation strategy but I'm unsure if it is worth coming up with one vs freezing the code.

The rest was covered in the previous answer but I'll repeat for ease of discover

The larger plan is to shift the focus of feature development in libtest to Cargo and custom test harness. In doing this, we may want to deprecate stable functionality that is redundant with Cargo. For unstable features, we may want to remove those in favor of them being implemented by Cargo or custom test harnesses. Finer details have not been worked out yet as right now our focus is more on json output to support shifting responsibilities to Cargo. As part of that, we are evaluating the needs for json output through writing a custom test harness which is letting us explore what other features will be needed as we work towards first-class custom test harnesses.

Amanieu · 2025-01-14T17:55:07Z

Thanks for the detailed response! We discussed this again in the libs-api meeting today and are happy to deprecate it.

@rfcbot merge

rfcbot · 2025-01-14T17:55:10Z

Team member @Amanieu has proposed to merge this. The next step is review by the rest of the tagged team members:

No concerns currently listed.

Once a majority of reviewers approve (and at most 2 approvals are outstanding), this will enter its final comment period. If you spot a major issue that hasn't been raised at any point in this process, please speak up!

See this document for info about what commands tagged team members can give me.

rfcbot · 2025-01-14T18:00:56Z

🔔 This is now entering its final comment period, as per the review above. 🔔

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 rust-lang#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 rust-lang#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 rust-lang#134283 Fixes rust-lang#133073

compiletest: Remove the `--logfile` flag This flag is deprecated in libtest (rust-lang#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 (rust-lang#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.

Rollup merge of rust-lang#139528 - Zalathar:no-logfile, r=jieyouxu compiletest: Remove the `--logfile` flag This flag is deprecated in libtest (rust-lang#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 (rust-lang#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.

Upstream changes relative to 1.85.1: Version 1.86.0 (2025-04-03) ========================== Language -------- - [Stabilize upcasting trait objects to supertraits.] (rust-lang/rust#134367) - [Allow safe functions to be marked with the `#[target_feature]` attribute.] (rust-lang/rust#134090) - [The `missing_abi` lint now warns-by-default.] (rust-lang/rust#132397) - Rust now lints about double negations, to catch cases that might have intended to be a prefix decrement operator (`--x`) as written in other languages. This was previously a clippy lint, `clippy::double_neg`, and is [now available directly in Rust as `double_negations`.] (rust-lang/rust#126604) - [More pointers are now detected as definitely not-null based on their alignment in const eval.] (rust-lang/rust#133700) - [Empty `repr()` attribute applied to invalid items are now correctly rejected.] (rust-lang/rust#133925) - [Inner attributes `#![test]` and `#![rustfmt::skip]` are no longer accepted in more places than intended.] (rust-lang/rust#134276) Compiler -------- - [Debug-assert that raw pointers are non-null on access.] (rust-lang/rust#134424) - [Change `-O` to mean `-C opt-level=3` instead of `-C opt-level=2` to match Cargo's defaults.] (rust-lang/rust#135439) - [Fix emission of `overflowing_literals` under certain macro environments.] (rust-lang/rust#136393) Platform Support ---------------- - [Replace `i686-unknown-redox` target with `i586-unknown-redox`.] (rust-lang/rust#136698) - [Increase baseline CPU of `i686-unknown-hurd-gnu` to Pentium 4.] (rust-lang/rust#136700) - New tier 3 targets: - [`{aarch64-unknown,x86_64-pc}-nto-qnx710_iosock`] (rust-lang/rust#133631). For supporting Neutrino QNX 7.1 with `io-socket` network stack. - [`{aarch64-unknown,x86_64-pc}-nto-qnx800`] (rust-lang/rust#133631). For supporting Neutrino QNX 8.0 (`no_std`-only). - [`{x86_64,i686}-win7-windows-gnu`] (rust-lang/rust#134609). Intended for backwards compatibility with Windows 7. `{x86_64,i686}-win7-windows-msvc` are the Windows MSVC counterparts that already exist as Tier 3 targets. - [`amdgcn-amd-amdhsa`](rust-lang/rust#134740). - [`x86_64-pc-cygwin`](rust-lang/rust#134999). - [`{mips,mipsel}-mti-none-elf`] (rust-lang/rust#135074). Initial bare-metal support. - [`m68k-unknown-none-elf`](rust-lang/rust#135085). - [`armv7a-nuttx-{eabi,eabihf}`, `aarch64-unknown-nuttx`, and `thumbv7a-nuttx-{eabi,eabihf}`] (rust-lang/rust#135757). Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - The type of `FromBytesWithNulError` in `CStr::from_bytes_with_nul(bytes: &[u8]) -> Result<&Self, FromBytesWithNulError>` was [changed from an opaque struct to an enum] (rust-lang/rust#134143), allowing users to examine why the conversion failed. - [Remove `RustcDecodable` and `RustcEncodable`.] (rust-lang/rust#134272) - [Deprecate libtest's `--logfile` option.] (rust-lang/rust#134283) - [On recent versions of Windows, `std::fs::remove_file` will now remove read-only files.] (rust-lang/rust#134679) Stabilized APIs --------------- - [`{float}::next_down`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_down) - [`{float}::next_up`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_up) - [`<[_]>::get_disjoint_mut`] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_mut) - [`<[_]>::get_disjoint_unchecked_mut`] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_unchecked_mut) - [`slice::GetDisjointMutError`] (https://doc.rust-lang.org/stable/std/slice/enum.GetDisjointMutError.html) - [`HashMap::get_disjoint_mut`] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_mut) - [`HashMap::get_disjoint_unchecked_mut`] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_unchecked_mut) - [`NonZero::count_ones`] (https://doc.rust-lang.org/stable/std/num/struct.NonZero.html#method.count_ones) - [`Vec::pop_if`] (https://doc.rust-lang.org/std/vec/struct.Vec.html#method.pop_if) - [`sync::Once::wait`] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait) - [`sync::Once::wait_force`] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait_force) - [`sync::OnceLock::wait`] (https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html#method.wait) These APIs are now stable in const contexts: - [`hint::black_box`] (https://doc.rust-lang.org/stable/std/hint/fn.black_box.html) - [`io::Cursor::get_mut`] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_mut) - [`io::Cursor::set_position`] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.set_position) - [`str::is_char_boundary`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.is_char_boundary) - [`str::split_at`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at) - [`str::split_at_checked`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_checked) - [`str::split_at_mut`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut) - [`str::split_at_mut_checked`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut_checked) Cargo ----- - [When merging, replace rather than combine configuration keys that refer to a program path and its arguments.] (rust-lang/cargo#15066) - [Error if both `--package` and `--workspace` are passed but the requested package is missing.] (rust-lang/cargo#15071) This was previously silently ignored, which was considered a bug since missing packages should be reported. - [Deprecate the token argument in `cargo login` to avoid shell history leaks.] (rust-lang/cargo#15057) - [Simplify the implementation of `SourceID` comparisons.] (rust-lang/cargo#14980) This may potentially change behavior if the canonicalized URL compares differently in alternative registries. Rustdoc ----- - [Add a sans-serif font setting.] (rust-lang/rust#133636) Compatibility Notes ------------------- - [The `wasm_c_abi` future compatibility warning is now a hard error.] (rust-lang/rust#133951) Users of `wasm-bindgen` should upgrade to at least version 0.2.89, otherwise compilation will fail. - [Remove long-deprecated no-op attributes `#![no_start]` and `#![crate_id]`.] (rust-lang/rust#134300) - [The future incompatibility lint `cenum_impl_drop_cast` has been made into a hard error.] (rust-lang/rust#135964) This means it is now an error to cast a field-less enum to an integer if the enum implements `Drop`. - [SSE2 is now required for "i686" 32-bit x86 hard-float targets; disabling it causes a warning that will become a hard error eventually.] (rust-lang/rust#137037) To compile for pre-SSE2 32-bit x86, use a "i586" target instead. Internal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Build the rustc on AArch64 Linux with ThinLTO + PGO.] (rust-lang/rust#133807) The ARM 64-bit compiler (AArch64) on Linux is now optimized with ThinLTO and PGO, similar to the optimizations we have already performed for the x86-64 compiler on Linux. This should make it up to 30% faster.

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 rust-lang#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 rust-lang#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 rust-lang#134283 Fixes rust-lang#133073

fix(test): Expose '--no-capture' in favor of `--nocapture` 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 rust-lang#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. I expect we'll warn about `--nocapture` being deprecated in the future after a sufficient transition period has been allowed. 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 rust-lang#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 rust-lang#134283 Regarding the implementation, I moved `--nocapture` out of `optgroups()`, into `parse_opts()`, out of an abundance of caution in passing the options without a deprecated value to the usage generation. However, the usage does not actually show optional flags, so this could potentially be dropped, simplifying the PR. Note: `compiletest` added `--no-capture` instead of `--nocapture` in rust-lang#134809 T-testing-devex FCP: rust-lang#133073 (comment) Fixes rust-lang#133073

Rollup merge of rust-lang#139224 - epage:nocapture, r=thomcc fix(test): Expose '--no-capture' in favor of `--nocapture` 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 rust-lang#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. I expect we'll warn about `--nocapture` being deprecated in the future after a sufficient transition period has been allowed. 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 rust-lang#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 rust-lang#134283 Regarding the implementation, I moved `--nocapture` out of `optgroups()`, into `parse_opts()`, out of an abundance of caution in passing the options without a deprecated value to the usage generation. However, the usage does not actually show optional flags, so this could potentially be dropped, simplifying the PR. Note: `compiletest` added `--no-capture` instead of `--nocapture` in rust-lang#134809 T-testing-devex FCP: rust-lang#133073 (comment) Fixes rust-lang#133073

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 rust-lang#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 rust-lang#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 rust-lang#134283 Fixes rust-lang#133073

fix(test): Expose '--no-capture' in favor of `--nocapture` 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 rust-lang#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. I expect we'll warn about `--nocapture` being deprecated in the future after a sufficient transition period has been allowed. 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 rust-lang#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 rust-lang#134283 Regarding the implementation, I moved `--nocapture` out of `optgroups()`, into `parse_opts()`, out of an abundance of caution in passing the options without a deprecated value to the usage generation. However, the usage does not actually show optional flags, so this could potentially be dropped, simplifying the PR. Note: `compiletest` added `--no-capture` instead of `--nocapture` in rust-lang#134809 T-testing-devex FCP: rust-lang#133073 (comment) Fixes rust-lang#133073

This MR contains the following updates: | Package | Update | Change | |---|---|---| | [rust](https://github.com/rust-lang/rust) | minor | `1.85.1` -> `1.86.0` | MR created with the help of [el-capitano/tools/renovate-bot](https://gitlab.com/el-capitano/tools/renovate-bot). **Proposed changes to behavior should be submitted there as MRs.** --- ### Release Notes <details> <summary>rust-lang/rust (rust)</summary> ### [`v1.86.0`](https://github.com/rust-lang/rust/blob/HEAD/RELEASES.md#Version-1860-2025-04-03) [Compare Source](rust-lang/rust@1.85.1...1.86.0) \========================== <a id="1.86.0-Language"></a> ## Language - [Stabilize upcasting trait objects to supertraits.](rust-lang/rust#134367) - [Allow safe functions to be marked with the `#[target_feature]` attribute.](rust-lang/rust#134090) - [The `missing_abi` lint now warns-by-default.](rust-lang/rust#132397) - Rust now lints about double negations, to catch cases that might have intended to be a prefix decrement operator (`--x`) as written in other languages. This was previously a clippy lint, `clippy::double_neg`, and is [now available directly in Rust as `double_negations`.](rust-lang/rust#126604) - [More pointers are now detected as definitely not-null based on their alignment in const eval.](rust-lang/rust#133700) - [Empty `repr()` attribute applied to invalid items are now correctly rejected.](rust-lang/rust#133925) - [Inner attributes `#![test]` and `#![rustfmt::skip]` are no longer accepted in more places than intended.](rust-lang/rust#134276) <a id="1.86.0-Compiler"></a> ## Compiler - [Debug-assert that raw pointers are non-null on access.](rust-lang/rust#134424) - [Change `-O` to mean `-C opt-level=3` instead of `-C opt-level=2` to match Cargo's defaults.](rust-lang/rust#135439) - [Fix emission of `overflowing_literals` under certain macro environments.](rust-lang/rust#136393) <a id="1.86.0-Platform-Support"></a> ## Platform Support - [Replace `i686-unknown-redox` target with `i586-unknown-redox`.](rust-lang/rust#136698) - [Increase baseline CPU of `i686-unknown-hurd-gnu` to Pentium 4.](rust-lang/rust#136700) - New tier 3 targets: - [`{aarch64-unknown,x86_64-pc}-nto-qnx710_iosock`](rust-lang/rust#133631). For supporting Neutrino QNX 7.1 with `io-socket` network stack. - [`{aarch64-unknown,x86_64-pc}-nto-qnx800`](rust-lang/rust#133631). For supporting Neutrino QNX 8.0 (`no_std`-only). - [`{x86_64,i686}-win7-windows-gnu`](rust-lang/rust#134609). Intended for backwards compatibility with Windows 7. `{x86_64,i686}-win7-windows-msvc` are the Windows MSVC counterparts that already exist as Tier 3 targets. - [`amdgcn-amd-amdhsa`](rust-lang/rust#134740). - [`x86_64-pc-cygwin`](rust-lang/rust#134999). - [`{mips,mipsel}-mti-none-elf`](rust-lang/rust#135074). Initial bare-metal support. - [`m68k-unknown-none-elf`](rust-lang/rust#135085). - [`armv7a-nuttx-{eabi,eabihf}`, `aarch64-unknown-nuttx`, and `thumbv7a-nuttx-{eabi,eabihf}`](rust-lang/rust#135757). Refer to Rust's \[platform support page]\[platform-support-doc] for more information on Rust's tiered platform support. <a id="1.86.0-Libraries"></a> ## Libraries - The type of `FromBytesWithNulError` in `CStr::from_bytes_with_nul(bytes: &[u8]) -> Result<&Self, FromBytesWithNulError>` was [changed from an opaque struct to an enum](rust-lang/rust#134143), allowing users to examine why the conversion failed. - [Remove `RustcDecodable` and `RustcEncodable`.](rust-lang/rust#134272) - [Deprecate libtest's `--logfile` option.](rust-lang/rust#134283) - [On recent versions of Windows, `std::fs::remove_file` will now remove read-only files.](rust-lang/rust#134679) <a id="1.86.0-Stabilized-APIs"></a> ## Stabilized APIs - [`{float}::next_down`](https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_down) - [`{float}::next_up`](https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_up) - [`<[_]>::get_disjoint_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_mut) - [`<[_]>::get_disjoint_unchecked_mut`](https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_unchecked_mut) - [`slice::GetDisjointMutError`](https://doc.rust-lang.org/stable/std/slice/enum.GetDisjointMutError.html) - [`HashMap::get_disjoint_mut`](https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_mut) - [`HashMap::get_disjoint_unchecked_mut`](https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_unchecked_mut) - [`NonZero::count_ones`](https://doc.rust-lang.org/stable/std/num/struct.NonZero.html#method.count_ones) - [`Vec::pop_if`](https://doc.rust-lang.org/std/vec/struct.Vec.html#method.pop_if) - [`sync::Once::wait`](https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait) - [`sync::Once::wait_force`](https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait_force) - [`sync::OnceLock::wait`](https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html#method.wait) These APIs are now stable in const contexts: - [`hint::black_box`](https://doc.rust-lang.org/stable/std/hint/fn.black_box.html) - [`io::Cursor::get_mut`](https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_mut) - [`io::Cursor::set_position`](https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.set_position) - [`str::is_char_boundary`](https://doc.rust-lang.org/stable/std/primitive.str.html#method.is_char_boundary) - [`str::split_at`](https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at) - [`str::split_at_checked`](https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_checked) - [`str::split_at_mut`](https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut) - [`str::split_at_mut_checked`](https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut_checked) <a id="1.86.0-Cargo"></a> ## Cargo - [When merging, replace rather than combine configuration keys that refer to a program path and its arguments.](rust-lang/cargo#15066) - [Error if both `--package` and `--workspace` are passed but the requested package is missing.](rust-lang/cargo#15071) This was previously silently ignored, which was considered a bug since missing packages should be reported. - [Deprecate the token argument in `cargo login` to avoid shell history leaks.](rust-lang/cargo#15057) - [Simplify the implementation of `SourceID` comparisons.](rust-lang/cargo#14980) This may potentially change behavior if the canonicalized URL compares differently in alternative registries. <a id="1.86.0-Rustdoc"></a> ## Rustdoc - [Add a sans-serif font setting.](rust-lang/rust#133636) <a id="1.86.0-Compatibility-Notes"></a> ## Compatibility Notes - [The `wasm_c_abi` future compatibility warning is now a hard error.](rust-lang/rust#133951) Users of `wasm-bindgen` should upgrade to at least version 0.2.89, otherwise compilation will fail. - [Remove long-deprecated no-op attributes `#![no_start]` and `#![crate_id]`.](rust-lang/rust#134300) - [The future incompatibility lint `cenum_impl_drop_cast` has been made into a hard error.](rust-lang/rust#135964) This means it is now an error to cast a field-less enum to an integer if the enum implements `Drop`. - [SSE2 is now required for "i686" 32-bit x86 hard-float targets; disabling it causes a warning that will become a hard error eventually.](rust-lang/rust#137037) To compile for pre-SSE2 32-bit x86, use a "i586" target instead. <a id="1.86.0-Internal-Changes"></a> ## Internal Changes These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Build the rustc on AArch64 Linux with ThinLTO + PGO.](rust-lang/rust#133807) The ARM 64-bit compiler (AArch64) on Linux is now optimized with ThinLTO and PGO, similar to the optimizations we have already performed for the x86-64 compiler on Linux. This should make it up to 30% faster. </details> --- ### Configuration 📅 **Schedule**: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined). 🚦 **Automerge**: Disabled by config. Please merge this manually once you are satisfied. ♻ **Rebasing**: Whenever MR becomes conflicted, or you tick the rebase/retry checkbox. 🔕 **Ignore**: Close this MR and you won't be reminded about this update again. --- - [ ] If you want to rebase/retry this MR, check this box --- This MR has been generated by [Renovate Bot](https://github.com/renovatebot/renovate).

Pkgsrc changes: * Drop support for building now old 1.76.0 rust natively on 32-bit NetBSD arm ports, pushing those to use the rust-bin variant instead. * Use of newer GCC on NetBSD/powerpc turned out to not be required, given that your kernel and user-land is new enough. >= 10.0 release? * Checksum updates. Upstream changes: Version 1.86.0 (2025-04-03) ========================== Language -------- - [Stabilize upcasting trait objects to supertraits.] (rust-lang/rust#134367) - [Allow safe functions to be marked with the `#[target_feature]` attribute.] (rust-lang/rust#134090) - [The `missing_abi` lint now warns-by-default.] (rust-lang/rust#132397) - Rust now lints about double negations, to catch cases that might have intended to be a prefix decrement operator (`--x`) as written in other languages. This was previously a clippy lint, `clippy::double_neg`, and is [now available directly in Rust as `double_negations`.] (rust-lang/rust#126604) - [More pointers are now detected as definitely not-null based on their alignment in const eval.] (rust-lang/rust#133700) - [Empty `repr()` attribute applied to invalid items are now correctly rejected.] (rust-lang/rust#133925) - [Inner attributes `#![test]` and `#![rustfmt::skip]` are no longer accepted in more places than intended.] (rust-lang/rust#134276) Compiler -------- - [Debug-assert that raw pointers are non-null on access.] (rust-lang/rust#134424) - [Change `-O` to mean `-C opt-level=3` instead of `-C opt-level=2` to match Cargo's defaults.] (rust-lang/rust#135439) - [Fix emission of `overflowing_literals` under certain macro environments.] (rust-lang/rust#136393) Platform Support ---------------- - [Replace `i686-unknown-redox` target with `i586-unknown-redox`.] (rust-lang/rust#136698) - [Increase baseline CPU of `i686-unknown-hurd-gnu` to Pentium 4.] (rust-lang/rust#136700) - New tier 3 targets: - [`{aarch64-unknown,x86_64-pc}-nto-qnx710_iosock`] (rust-lang/rust#133631). For supporting Neutrino QNX 7.1 with `io-socket` network stack. - [`{aarch64-unknown,x86_64-pc}-nto-qnx800`] (rust-lang/rust#133631). For supporting Neutrino QNX 8.0 (`no_std`-only). - [`{x86_64,i686}-win7-windows-gnu`] (rust-lang/rust#134609). Intended for backwards compatibility with Windows 7. `{x86_64,i686}-win7-windows-msvc` are the Windows MSVC counterparts that already exist as Tier 3 targets. - [`amdgcn-amd-amdhsa`](rust-lang/rust#134740). - [`x86_64-pc-cygwin`](rust-lang/rust#134999). - [`{mips,mipsel}-mti-none-elf`] (rust-lang/rust#135074). Initial bare-metal support. - [`m68k-unknown-none-elf`](rust-lang/rust#135085). - [`armv7a-nuttx-{eabi,eabihf}`, `aarch64-unknown-nuttx`, and `thumbv7a-nuttx-{eabi,eabihf}`] (rust-lang/rust#135757). Refer to Rust's [platform support page][platform-support-doc] for more information on Rust's tiered platform support. Libraries --------- - The type of `FromBytesWithNulError` in `CStr::from_bytes_with_nul(bytes: &[u8]) -> Result<&Self, FromBytesWithNulError>` was [changed from an opaque struct to an enum] (rust-lang/rust#134143), allowing users to examine why the conversion failed. - [Remove `RustcDecodable` and `RustcEncodable`.] (rust-lang/rust#134272) - [Deprecate libtest's `--logfile` option.] (rust-lang/rust#134283) - [On recent versions of Windows, `std::fs::remove_file` will now remove read-only files.] (rust-lang/rust#134679) Stabilized APIs --------------- - [`{float}::next_down`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_down) - [`{float}::next_up`] (https://doc.rust-lang.org/stable/std/primitive.f64.html#method.next_up) - [`<[_]>::get_disjoint_mut`] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_mut) - [`<[_]>::get_disjoint_unchecked_mut`] (https://doc.rust-lang.org/stable/std/primitive.slice.html#method.get_disjoint_unchecked_mut) - [`slice::GetDisjointMutError`] (https://doc.rust-lang.org/stable/std/slice/enum.GetDisjointMutError.html) - [`HashMap::get_disjoint_mut`] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_mut) - [`HashMap::get_disjoint_unchecked_mut`] (https://doc.rust-lang.org/std/collections/hash_map/struct.HashMap.html#method.get_disjoint_unchecked_mut) - [`NonZero::count_ones`] (https://doc.rust-lang.org/stable/std/num/struct.NonZero.html#method.count_ones) - [`Vec::pop_if`] (https://doc.rust-lang.org/std/vec/struct.Vec.html#method.pop_if) - [`sync::Once::wait`] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait) - [`sync::Once::wait_force`] (https://doc.rust-lang.org/stable/std/sync/struct.Once.html#method.wait_force) - [`sync::OnceLock::wait`] (https://doc.rust-lang.org/stable/std/sync/struct.OnceLock.html#method.wait) These APIs are now stable in const contexts: - [`hint::black_box`] (https://doc.rust-lang.org/stable/std/hint/fn.black_box.html) - [`io::Cursor::get_mut`] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.get_mut) - [`io::Cursor::set_position`] (https://doc.rust-lang.org/stable/std/io/struct.Cursor.html#method.set_position) - [`str::is_char_boundary`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.is_char_boundary) - [`str::split_at`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at) - [`str::split_at_checked`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_checked) - [`str::split_at_mut`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut) - [`str::split_at_mut_checked`] (https://doc.rust-lang.org/stable/std/primitive.str.html#method.split_at_mut_checked) Cargo ----- - [When merging, replace rather than combine configuration keys that refer to a program path and its arguments.] (rust-lang/cargo#15066) - [Error if both `--package` and `--workspace` are passed but the requested package is missing.] (rust-lang/cargo#15071) This was previously silently ignored, which was considered a bug since missing packages should be reported. - [Deprecate the token argument in `cargo login` to avoid shell history leaks.] (rust-lang/cargo#15057) - [Simplify the implementation of `SourceID` comparisons.] (rust-lang/cargo#14980) This may potentially change behavior if the canonicalized URL compares differently in alternative registries. Rustdoc ----- - [Add a sans-serif font setting.] (rust-lang/rust#133636) Compatibility Notes ------------------- - [The `wasm_c_abi` future compatibility warning is now a hard error.] (rust-lang/rust#133951) Users of `wasm-bindgen` should upgrade to at least version 0.2.89, otherwise compilation will fail. - [Remove long-deprecated no-op attributes `#![no_start]` and `#![crate_id]`.] (rust-lang/rust#134300) - [The future incompatibility lint `cenum_impl_drop_cast` has been made into a hard error.] (rust-lang/rust#135964) This means it is now an error to cast a field-less enum to an integer if the enum implements `Drop`. - [SSE2 is now required for "i686" 32-bit x86 hard-float targets; disabling it causes a warning that will become a hard error eventually.] (rust-lang/rust#137037) To compile for pre-SSE2 32-bit x86, use a "i586" target instead. Internal Changes ---------------- These changes do not affect any public interfaces of Rust, but they represent significant improvements to the performance or internals of rustc and related tools. - [Build the rustc on AArch64 Linux with ThinLTO + PGO.] (rust-lang/rust#133807) The ARM 64-bit compiler (AArch64) on Linux is now optimized with ThinLTO and PGO, similar to the optimizations we have already performed for the x86-64 compiler on Linux. This should make it up to 30% faster.

## Summary - scripts/targets/repeat-test.sh のプリフライトのコメントを、libtest の --logfile の実測に合わせて修正 Closes #3036 ## 対象外（out-of-scope） - #3036 へ調査結果コメントを投稿（1.99.0・1.86.0 deprecated・rust-lang/rust#134283・#49359・#140805・切り替え方式・見直しのきっかけ・実測 rc）。未実施 - libtest の --nocapture（1.88.0 で deprecated）を --no-capture へ置き換える追跡 issue の起票（repeat-test.sh の LOGARGS+=(--nocapture) ほか）。未実施 - --logfile から stable な代替（--test-results-output 等）への移行は stable 化後（見直しのきっかけ） 🤖 Generated with [Claude Code](https://claude.com/claude-code)  --- > [!NOTE] > **Low Risk** > Comment-only change in a CI helper script; no executable behavior is modified. > > **Overview** > Updates the **preflight** comment in `scripts/targets/repeat-test.sh` (issue **#3036**) so it matches measured **libtest** behavior. The old text said **`--list`** does not create a logfile; the new text notes that **`--list` with `--logfile`** can still create an **empty** logfile (observed on **1.99.0** with zero tests), that preflight does **not** validate file contents, and that cleanup after a successful check remains unchanged—per-run log verification still happens in the main loop. > > **No script logic changes**—documentation only. > > <sup>Reviewed by [Cursor Bugbot](https://cursor.com/bugbot) for commit 2e78a07. Bugbot is set up for automated code reviews on this repo. Configure [here](https://www.cursor.com/dashboard/bugbot).</sup>  Co-authored-by: Claude Sonnet 5.5 <noreply@anthropic.com>

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rustbot added S-waiting-on-review Status: Awaiting review from the assignee but also interested parties. T-libs Relevant to the library team, which will review and decide on the PR/issue. labels Dec 13, 2024

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epage force-pushed the logfile branch from 4b68c33 to 93e93b7 Compare December 13, 2024 21:17

rustbot added the T-libs-api [DEPRECATED; DO NOT USE] label Dec 13, 2024

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epage added the I-libs-api-nominated [DEPRECATED; DO NOT USE] label Dec 17, 2024

m-ou-se reviewed Jan 7, 2025

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Comment thread library/test/src/options.rs Resolved

epage force-pushed the logfile branch 2 times, most recently from eedd0a3 to 450aaa4 Compare January 7, 2025 16:57

epage force-pushed the logfile branch from 450aaa4 to 502f647 Compare January 7, 2025 16:59

Amanieu removed the T-libs Relevant to the library team, which will review and decide on the PR/issue. label Jan 14, 2025

Amanieu removed the I-libs-api-nominated [DEPRECATED; DO NOT USE] label Jan 14, 2025

rfcbot added finished-final-comment-period The final comment period is finished for this PR / Issue. and removed final-comment-period In the final comment period and will be merged soon unless new substantive objections are raised. labels Jan 24, 2025

epage mentioned this pull request Apr 1, 2025

fix(test): Expose '--no-capture' in favor of --nocapture #139224

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vigoo mentioned this pull request Apr 3, 2025

logfile parameter got deprecated in libtest vigoo/test-r#105

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Zalathar mentioned this pull request Apr 8, 2025

compiletest: Remove the --logfile flag #139528

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apiraino removed the to-announce Announce this issue on triage meeting label Apr 30, 2025

This was referenced Sep 5, 2025

libtest json output gets intermixed with non-captured output from tests #132135

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Running cargo test -- --logfile log.txt overrides test results when running multiple testers #105424

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aLiz-Nancy mentioned this pull request Oct 28, 2026

docs(ci): repeat-test のプリフライトの logfile 記述を実測に合わせる (REPAIR-12) Fandhe-AI/fandhe-container#3253

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aLiz-Nancy mentioned this pull request Oct 28, 2026

ci: repeat-test が使う libtest の --logfile の廃止に備えた恒久策を調べて決める (REPAIR-12) Fandhe-AI/fandhe-container#3036

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fix(libtest): Deprecate '--logfile' - #134283

fix(libtest): Deprecate '--logfile'#134283
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