Docs: added brief colon explanation

[zedddie16]

#131865

[rustbot]

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[rust-log-analyzer]

The job mingw-check-tidy failed! Check out the build log: (web) (plain)

Click to see the possible cause of the failure (guessed by this bot)

COPY host-x86_64/mingw-check/validate-toolstate.sh /scripts/
COPY host-x86_64/mingw-check/validate-error-codes.sh /scripts/

# NOTE: intentionally uses python2 for x.py so we can test it still works.
# validate-toolstate only runs in our CI, so it's ok for it to only support python3.
ENV SCRIPT TIDY_PRINT_DIFF=1 python2.7 ../x.py test \
           --stage 0 src/tools/tidy tidyselftest --extra-checks=py:lint,cpp:fmt
# This file is autogenerated by pip-compile with Python 3.10
# by the following command:
#
#    pip-compile --allow-unsafe --generate-hashes reuse-requirements.in
---
#13 2.959 Building wheels for collected packages: reuse
#13 2.960   Building wheel for reuse (pyproject.toml): started
#13 3.210   Building wheel for reuse (pyproject.toml): finished with status 'done'
#13 3.211   Created wheel for reuse: filename=reuse-4.0.3-cp310-cp310-manylinux_2_35_x86_64.whl size=132720 sha256=026f3bb0f1aa8090b861fd0a0939cb1a782396d84c8aab7875096557d637a0f6
#13 3.211   Stored in directory: /tmp/pip-ephem-wheel-cache-urwp_vgv/wheels/3d/8d/0a/e0fc6aba4494b28a967ab5eaf951c121d9c677958714e34532
#13 3.214 Installing collected packages: boolean-py, binaryornot, tomlkit, reuse, python-debian, markupsafe, license-expression, jinja2, chardet, attrs
#13 3.623 Successfully installed attrs-23.2.0 binaryornot-0.4.4 boolean-py-4.0 chardet-5.2.0 jinja2-3.1.4 license-expression-30.3.0 markupsafe-2.1.5 python-debian-0.1.49 reuse-4.0.3 tomlkit-0.13.0
#13 3.624 WARNING: Running pip as the 'root' user can result in broken permissions and conflicting behaviour with the system package manager. It is recommended to use a virtual environment instead: https://pip.pypa.io/warnings/venv
#13 4.184 Collecting virtualenv
#13 4.184 Collecting virtualenv
#13 4.236   Downloading virtualenv-20.27.1-py3-none-any.whl (3.1 MB)
#13 4.368      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 3.1/3.1 MB 24.1 MB/s eta 0:00:00
#13 4.426 Collecting platformdirs<5,>=3.9.1
#13 4.434   Downloading platformdirs-4.3.6-py3-none-any.whl (18 kB)
#13 4.456 Collecting distlib<1,>=0.3.7
#13 4.477      ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 469.0/469.0 KB 42.9 MB/s eta 0:00:00
#13 4.515 Collecting filelock<4,>=3.12.2
#13 4.522   Downloading filelock-3.16.1-py3-none-any.whl (16 kB)
#13 4.522   Downloading filelock-3.16.1-py3-none-any.whl (16 kB)
#13 4.605 Installing collected packages: distlib, platformdirs, filelock, virtualenv
#13 4.783 Successfully installed distlib-0.3.9 filelock-3.16.1 platformdirs-4.3.6 virtualenv-20.27.1
#13 DONE 4.9s

#14 [7/8] COPY host-x86_64/mingw-check/validate-toolstate.sh /scripts/
#14 DONE 0.0s
---
DirectMap4k:      182208 kB
DirectMap2M:     7157760 kB
DirectMap1G:    11534336 kB
##[endgroup]
Executing TIDY_PRINT_DIFF=1 python2.7 ../x.py test            --stage 0 src/tools/tidy tidyselftest --extra-checks=py:lint,cpp:fmt
+ TIDY_PRINT_DIFF=1 python2.7 ../x.py test --stage 0 src/tools/tidy tidyselftest --extra-checks=py:lint,cpp:fmt
    Finished `dev` profile [unoptimized] target(s) in 0.04s
##[endgroup]
downloading https://static.rust-lang.org/dist/2024-10-16/rustfmt-nightly-x86_64-unknown-linux-gnu.tar.xz
extracting /checkout/obj/build/cache/2024-10-16/rustfmt-nightly-x86_64-unknown-linux-gnu.tar.xz to /checkout/obj/build/x86_64-unknown-linux-gnu/rustfmt
---
Diff in /checkout/library/alloc/src/fmt.rs:589:
 pub use core::fmt::Alignment;
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::fmt::Error;
-#[unstable(feature = "debug_closure_helpers", issue = "117729")]
-pub use core::fmt::{from_fn, FromFn};
 #[stable(feature = "rust1", since = "1.0.0")]
-pub use core::fmt::{write, Arguments};
+pub use core::fmt::{Arguments, write};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::fmt::{Binary, Octal};
 #[stable(feature = "rust1", since = "1.0.0")]
Diff in /checkout/library/alloc/src/fmt.rs:601:
 pub use core::fmt::{DebugList, DebugMap, DebugSet, DebugStruct, DebugTuple};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::fmt::{Formatter, Result, Write};
+#[unstable(feature = "debug_closure_helpers", issue = "117729")]
+pub use core::fmt::{FromFn, from_fn};
 #[stable(feature = "rust1", since = "1.0.0")]
 pub use core::fmt::{LowerExp, UpperExp};
 #[stable(feature = "rust1", since = "1.0.0")]
fmt error: Running `"/checkout/obj/build/x86_64-unknown-linux-gnu/rustfmt/bin/rustfmt" "--config-path" "/checkout" "--edition" "2021" "--unstable-features" "--skip-children" "--check" "/checkout/library/core/tests/net/parser.rs" "/checkout/library/core/tests/net/ip_addr.rs" "/checkout/library/core/tests/net/socket_addr.rs" "/checkout/library/core/tests/net/mod.rs" "/checkout/library/core/tests/atomic.rs" "/checkout/library/core/tests/ptr.rs" "/checkout/library/core/tests/const_ptr.rs" "/checkout/library/core/tests/str.rs" "/checkout/library/alloc/src/alloc/tests.rs" "/checkout/library/core/tests/ffi/cstr.rs" "/checkout/library/alloc/src/slice.rs" "/checkout/library/alloc/src/string.rs" "/checkout/library/core/tests/cell.rs" "/checkout/library/core/tests/ffi.rs" "/checkout/library/alloc/src/rc/tests.rs" "/checkout/library/alloc/src/lib.miri.rs" "/checkout/library/alloc/src/tests.rs" "/checkout/library/alloc/src/boxed.rs" "/checkout/library/alloc/src/rc.rs" "/checkout/library/alloc/src/str.rs" "/checkout/library/core/tests/ops/control_flow.rs" "/checkout/library/core/tests/ops/from_residual.rs" "/checkout/library/core/tests/ascii.rs" "/checkout/library/core/tests/lib.rs" "/checkout/library/core/tests/pattern.rs" "/checkout/library/core/tests/tuple.rs" "/checkout/library/core/tests/option.rs" "/checkout/library/core/tests/panic/location.rs" "/checkout/library/core/tests/result.rs" "/checkout/library/alloc/src/ffi/c_str.rs" "/checkout/library/core/tests/macros.rs" "/checkout/library/alloc/src/ffi/c_str/tests.rs" "/checkout/library/alloc/src/ffi/mod.rs" "/checkout/library/alloc/src/raw_vec/tests.rs" "/checkout/library/alloc/src/lib.rs" "/checkout/library/alloc/src/macros.rs" "/checkout/library/core/tests/iter/traits/double_ended.rs" "/checkout/library/core/tests/iter/traits/accum.rs" "/checkout/library/core/tests/iter/traits/step.rs" "/checkout/library/core/tests/iter/traits/iterator.rs" "/checkout/library/core/tests/iter/traits/mod.rs" "/checkout/library/alloc/src/vec/extract_if.rs" "/checkout/library/alloc/src/vec/spec_from_iter_nested.rs" "/checkout/library/alloc/src/vec/splice.rs" "/checkout/library/alloc/src/vec/spec_extend.rs" "/checkout/library/alloc/src/vec/spec_from_elem.rs" "/checkout/library/alloc/src/vec/is_zero.rs" "/checkout/library/alloc/src/vec/partial_eq.rs" "/checkout/library/alloc/src/vec/in_place_drop.rs" "/checkout/library/alloc/src/vec/cow.rs" "/checkout/library/alloc/src/vec/set_len_on_drop.rs" "/checkout/library/alloc/src/vec/into_iter.rs" "/checkout/library/alloc/src/vec/in_place_collect.rs" "/checkout/library/alloc/src/vec/spec_from_iter.rs" "/checkout/library/alloc/src/vec/mod.rs" "/checkout/library/alloc/src/vec/drain.rs" "/checkout/library/alloc/src/testing/ord_chaos.rs" "/checkout/library/alloc/src/testing/crash_test.rs" "/checkout/library/alloc/src/testing/rng.rs" "/checkout/library/alloc/src/testing/mod.rs" "/checkout/library/alloc/src/fmt.rs" "/checkout/library/windows_targets/src/lib.rs" "/checkout/library/core/tests/iter/mod.rs" "/checkout/library/alloc/src/task.rs"` failed.
If you're running `tidy`, try again with `--bless`. Or, if you just want to format code, run `./x.py fmt` instead.
  local time: Tue Oct 29 20:13:36 UTC 2024
  network time: Tue, 29 Oct 2024 20:13:36 GMT
##[error]Process completed with exit code 1.
Post job cleanup.