move never type tests to subdirectories and add some comments

[WaffleLapkin]

This hopefully makes things a little bit clearer

[rustbot]

r? @petrochenkov

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[rust-log-analyzer]

The job tidy failed! Check out the build log: (web) (plain enhanced) (plain)

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

[TIMING:end] tool::Tidy { compiler: Compiler { stage: 0, host: x86_64-unknown-linux-gnu, forced_compiler: false }, target: x86_64-unknown-linux-gnu } -- 0.000
fmt check
fmt: checked 6724 files
tidy check
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-5500-1.rs` to `{reason}-issue-5500.rs`
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-44402.rs` to `{reason}-issue-44402.rs`
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-52443.rs` to `{reason}-issue-52443.rs`
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-51506.rs` to `{reason}-issue-51506.rs`
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-13352.rs` to `{reason}-issue-13352.rs`
tidy [ui_tests (tests)]: issue-number-only test names are not descriptive, consider renaming file `tests/ui/never_type/regress/issue-96335.rs` to `{reason}-issue-96335.rs`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-10176.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-13352.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-2149.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-44402.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-51506.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-52443.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-5500-1.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: file `/checkout/tests/ui/never_type/issue-96335.rs` no longer exists and should be removed from the exclusions in `src/tools/tidy/src/issues.txt`
tidy [ui_tests (tests)]: FAIL
tidy [rustdoc_json (src)]: `rustdoc-json-types` modified, checking format version
tidy: Skipping binary file check, read-only filesystem
removing old virtual environment
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'venv'
creating virtual environment at '/checkout/obj/build/venv' using 'python3.10' and 'virtualenv'
---
linting javascript files
Running eslint on rustdoc JS files
info: ES-Check: there were no ES version matching errors!  🎉
typechecking javascript files
tidy: The following check failed: ui_tests (tests)
Command `/checkout/obj/build/x86_64-unknown-linux-gnu/stage1-tools-bin/rust-tidy --root-path=/checkout --cargo-path=/checkout/obj/build/x86_64-unknown-linux-gnu/stage0/bin/cargo --output-dir=/checkout/obj/build --concurrency=4 --npm-path=/node/bin/yarn --ci=true --extra-checks=py,cpp,js,spellcheck` failed with exit code 1
Created at: src/bootstrap/src/core/build_steps/tool.rs:1612:23
Executed at: src/bootstrap/src/core/build_steps/test.rs:1382:29

Command has failed. Rerun with -v to see more details.
Bootstrap failed while executing `test src/tools/tidy tidyselftest --extra-checks=py,cpp,js,spellcheck`
Build completed unsuccessfully in 0:03:00
  local time: Tue Mar  3 13:36:06 UTC 2026
  network time: Tue, 03 Mar 2026 13:36:06 GMT
##[error]Process completed with exit code 1.