Deprecate RUST_TEST_* env variables #145269
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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.
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We discussed this in the @rust-lang/libs-api meeting and are happy to accept this change. More generally, we're inclined to fully delegate all authority over libtest to the testing-devex team so this should not require a libs-api FCP: rust-lang/libs-team#633 |
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Sounds like this is good as-is then. If not, it's trivial enough to roll back given that it's solely text updates and not code. @bors r+ rollup |
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Deprecate RUST_TEST_* env variables Like with rust-lang#139224, 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. For testing-devex FCP, see rust-lang/testing-devex-team#10 Fixes rust-lang/testing-devex-team#10 History ------- At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope. At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem. **Originally:** `RUST_THREADS` was respected by the Rust runtime and libextra/test got this for free **2013:** rust-lang#7335 suggested splitting `RUST_TEST_TASKS` out of `RUST_THREADS`. In that issue and the implementation (rust-lang#8823). **2014:** rust-lang#13374 ask for support to disable capturing of stdout/stderr. `--nocapture` and `RUST_TEST_NOCAPTURE` were added together. **2015:** rust-lang#23525 renamed `RUST_TEST_TASKS` to `RUST_TEST_THREADS` **2016:** rust-lang#25636 asked to configure `RUST_TEST_THREADS` via `--test-threads` which was implemented in rust-lang#35414 **2021:** rust-lang#85440 asked for test randomization which was implemented in rust-lang#89082, adding `--shuffle` / RUST_TEST_SHUFFLE` and `--shuffle-seed SEED` / `RUST_TEST_SHUFFLE_SEED` Potentially relevant issues --------------------------- - rust-lang#74845
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Deprecate RUST_TEST_* env variables Like with rust-lang#139224, 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. For testing-devex FCP, see rust-lang/testing-devex-team#10 Fixes rust-lang/testing-devex-team#10 History ------- At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope. At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem. **Originally:** `RUST_THREADS` was respected by the Rust runtime and libextra/test got this for free **2013:** rust-lang#7335 suggested splitting `RUST_TEST_TASKS` out of `RUST_THREADS`. In that issue and the implementation (rust-lang#8823). **2014:** rust-lang#13374 ask for support to disable capturing of stdout/stderr. `--nocapture` and `RUST_TEST_NOCAPTURE` were added together. **2015:** rust-lang#23525 renamed `RUST_TEST_TASKS` to `RUST_TEST_THREADS` **2016:** rust-lang#25636 asked to configure `RUST_TEST_THREADS` via `--test-threads` which was implemented in rust-lang#35414 **2021:** rust-lang#85440 asked for test randomization which was implemented in rust-lang#89082, adding `--shuffle` / RUST_TEST_SHUFFLE` and `--shuffle-seed SEED` / `RUST_TEST_SHUFFLE_SEED` Potentially relevant issues --------------------------- - rust-lang#74845
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Deprecate RUST_TEST_* env variables Like with rust-lang#139224, 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. For testing-devex FCP, see rust-lang/testing-devex-team#10 Fixes rust-lang/testing-devex-team#10 History ------- At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope. At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem. **Originally:** `RUST_THREADS` was respected by the Rust runtime and libextra/test got this for free **2013:** rust-lang#7335 suggested splitting `RUST_TEST_TASKS` out of `RUST_THREADS`. In that issue and the implementation (rust-lang#8823). **2014:** rust-lang#13374 ask for support to disable capturing of stdout/stderr. `--nocapture` and `RUST_TEST_NOCAPTURE` were added together. **2015:** rust-lang#23525 renamed `RUST_TEST_TASKS` to `RUST_TEST_THREADS` **2016:** rust-lang#25636 asked to configure `RUST_TEST_THREADS` via `--test-threads` which was implemented in rust-lang#35414 **2021:** rust-lang#85440 asked for test randomization which was implemented in rust-lang#89082, adding `--shuffle` / RUST_TEST_SHUFFLE` and `--shuffle-seed SEED` / `RUST_TEST_SHUFFLE_SEED` Potentially relevant issues --------------------------- - rust-lang#74845
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Deprecate RUST_TEST_* env variables Like with rust-lang#139224, 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. For testing-devex FCP, see rust-lang/testing-devex-team#10 Fixes rust-lang/testing-devex-team#10 History ------- At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope. At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem. **Originally:** `RUST_THREADS` was respected by the Rust runtime and libextra/test got this for free **2013:** rust-lang#7335 suggested splitting `RUST_TEST_TASKS` out of `RUST_THREADS`. In that issue and the implementation (rust-lang#8823). **2014:** rust-lang#13374 ask for support to disable capturing of stdout/stderr. `--nocapture` and `RUST_TEST_NOCAPTURE` were added together. **2015:** rust-lang#23525 renamed `RUST_TEST_TASKS` to `RUST_TEST_THREADS` **2016:** rust-lang#25636 asked to configure `RUST_TEST_THREADS` via `--test-threads` which was implemented in rust-lang#35414 **2021:** rust-lang#85440 asked for test randomization which was implemented in rust-lang#89082, adding `--shuffle` / RUST_TEST_SHUFFLE` and `--shuffle-seed SEED` / `RUST_TEST_SHUFFLE_SEED` Potentially relevant issues --------------------------- - rust-lang#74845
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Rollup of 7 pull requests Successful merges: - #144642 (editorconfig: don't trim trailing whitespace in tests) - #144955 (search graph: lazily update parent goals) - #145153 (Handle macros with multiple kinds, and improve errors) - #145250 (Add regression test for former ICE involving malformed meta items containing interpolated tokens) - #145269 (Deprecate RUST_TEST_* env variables) - #145289 (chore(ci): upgrade checkout to v5) - #145303 (Docs: Link to payload_as_str() from payload().) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 7 pull requests Successful merges: - #144642 (editorconfig: don't trim trailing whitespace in tests) - #144955 (search graph: lazily update parent goals) - #145153 (Handle macros with multiple kinds, and improve errors) - #145250 (Add regression test for former ICE involving malformed meta items containing interpolated tokens) - #145269 (Deprecate RUST_TEST_* env variables) - #145289 (chore(ci): upgrade checkout to v5) - #145303 (Docs: Link to payload_as_str() from payload().) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup of 11 pull requests Successful merges: - #143467 (Add ASCII-related methods from `u8` and `MIN`/`MAX` to `core::ascii::Char`) - #144519 (Constify `SystemTime` methods) - #144642 (editorconfig: don't trim trailing whitespace in tests) - #144870 (Stabilize `path_file_prefix` feature) - #145269 (Deprecate RUST_TEST_* env variables) - #145274 (Remove unused `#[must_use]`) - #145289 (chore(ci): upgrade checkout to v5) - #145303 (Docs: Link to payload_as_str() from payload().) - #145308 (Adjust documentation of `dangling`) - #145320 (Allow cross-compiling the Cranelift dist component) - #145325 (Add `cast_init` and `cast_uninit` methods for pointers) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of #145269 - epage:test-env, r=jhpratt Deprecate RUST_TEST_* env variables Like with #139224, 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. For testing-devex FCP, see rust-lang/testing-devex-team#10 Fixes rust-lang/testing-devex-team#10 History ------- At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope. At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem. **Originally:** `RUST_THREADS` was respected by the Rust runtime and libextra/test got this for free **2013:** #7335 suggested splitting `RUST_TEST_TASKS` out of `RUST_THREADS`. In that issue and the implementation (#8823). **2014:** #13374 ask for support to disable capturing of stdout/stderr. `--nocapture` and `RUST_TEST_NOCAPTURE` were added together. **2015:** #23525 renamed `RUST_TEST_TASKS` to `RUST_TEST_THREADS` **2016:** #25636 asked to configure `RUST_TEST_THREADS` via `--test-threads` which was implemented in #35414 **2021:** #85440 asked for test randomization which was implemented in #89082, adding `--shuffle` / RUST_TEST_SHUFFLE` and `--shuffle-seed SEED` / `RUST_TEST_SHUFFLE_SEED` Potentially relevant issues --------------------------- - #74845
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Like with #139224, this is a documentation-only deprecation for now. Over time, we can
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.tomlas well as environment variables).This would include:
RUST_TEST_THREADSRUST_TEST_NOCAPTURERUST_TEST_SHUFFLE(unstable)RUST_TEST_SHUFFLE_SEED(unstable)The primary outcomes for this change are
cargo test, are expected to track when they are being bypassed to protect against negative interactions, e.g.RUST_TEST_NOCAPTURE=1when json output is being read.For testing-devex FCP, see rust-lang/testing-devex-team#10
Fixes rust-lang/testing-devex-team#10
History
At each step, I could not find evidence of design discussions on whether to support CLI, env, or both. The first env variable seems to come from the fact that it was being forked out of an existing env variable that had a much wider scope.
At best, this seems like a way to offer a more persistent configuration for these flags but environment variables hidden away in libtest is a bit clunky and this seems like the wrong layer to handle this problem.
Originally:
RUST_THREADSwas respected by the Rust runtime and libextra/test got this for free2013: #7335 suggested splitting
RUST_TEST_TASKSout ofRUST_THREADS. In that issue and the implementation (#8823).2014: #13374 ask for support to disable capturing of stdout/stderr.
--nocaptureandRUST_TEST_NOCAPTUREwere added together.2015: #23525 renamed
RUST_TEST_TASKStoRUST_TEST_THREADS2016: #25636 asked to configure
RUST_TEST_THREADSvia--test-threadswhich was implemented in #354142021: #85440 asked for test randomization which was implemented in #89082, adding
--shuffle/ RUST_TEST_SHUFFLEand--shuffle-seed SEED/RUST_TEST_SHUFFLE_SEED`Potentially relevant issues