`mdbook test` fails on commit 26404744

[luandy64]

Followed the README to run mdbook test and got the following error.

2022-12-22 23:35:37 [ERROR] (mdbook::book): rustdoc returned an error:

--- stdout

running 2 tests
test /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md - Scoped_Threads (line 19) ... FAILED
test /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md - Scoped_Threads (line 5) - compile fail ... ok

failures:

---- /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md - Scoped_Threads (line 19) stdout ----
error[E0658]: use of unstable library feature 'scoped_threads'
 --> /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md:25:5
  |
7 |     thread::scope(|scope| {
  |     ^^^^^^^^^^^^^
  |
  = note: see issue #93203 <https://github.com/rust-lang/rust/issues/93203> for more information

error[E0658]: use of unstable library feature 'scoped_threads'
 --> /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md:26:15
  |
8 |         scope.spawn(|| {
  |               ^^^^^
  |
  = note: see issue #93203 <https://github.com/rust-lang/rust/issues/93203> for more information

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0658`.
Couldn't compile the test.

failures:
    /var/folders/3h/t8595zjd10l4248jh4z21h8r0000gn/T/mdbook-ozrGSf/concurrency/scoped-threads.md - Scoped_Threads (line 19)

test result: FAILED. 1 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 0.04s


--- stderr

[mgeisler]

Hi @luandy64, thanks for reporting this!

I believe the problem is that thread::scope became stable just a few releases ago in version 1.63.0. Can you try again with the current stable Rust release?

[mgeisler]

Hi @luandy64, mdbook test work in CI, so I believe the problem is just that your Rust version was too old. Please report back if you keep seeing the problem after a rustup update. Thanks!