ARROW-10929: [Rust] Change CI to use Stable Rust

[alamb]

This is a cherry-pick of jorgecarleitao@ca66d6d by @jorgecarleitao

It runs all tests except the simd using stable -- The SIMD feature still require nightly rust, but the default features do not (after #8698)

Update: It also silences a few clippy lints which start complaining on stable -- I'll comment inline

[github-actions]

https://issues.apache.org/jira/browse/ARROW-10929

[alamb]

🤔 the windows CI build is failing when using stable:

failures:

---- encodings::encoding::tests::test_bool stdout ----
thread 'encodings::encoding::tests::test_bool' panicked at 'Invalid byte when reading bool', parquet\src\util\bit_util.rs:73:18

[alamb]

Hmm, I ran everything under valgrind locally and it did not detect any errors and the test has passed on windows a subsequent run. However, now I am getting a clippy error. I will fix that.

[andygrove]

thinking the windows CI build is failing when using stable:

failures:

---- encodings::encoding::tests::test_bool stdout ----
thread 'encodings::encoding::tests::test_bool' panicked at 'Invalid byte when reading bool', parquet\src\util\bit_util.rs:73:18

I just saw this locally too and it passed on a second run. I filed https://issues.apache.org/jira/browse/ARROW-10943

[alamb]

this does not exist in stable clippy

[alamb]

Clippy is complaining about https://rust-lang.github.io/rust-clippy/master/index.html#rc_buffer - but I think in this case using the Arc is really about cheaply copying the String rather than it being mutable. The same happens for the other places I disabled this lint in this PR

I am not enough of a Rust expert to know if there is some better way to pass around a cheaply cloneable Vec or String that would appease Clippy.

[Dandandan]

Did it give an alternative in the suggestion?

Looks like Arc<str> and Arc<[T]> should be the alternatives

[jorgecarleitao]

I agree @Dandandan . I changed then a couple of times, but since the focus of this PR was the CI in stable, which includes build, tests, etc. I considered clippy to be a minor hassle that we can deal with later.

[alamb]

@Dandandan -- It did give alternatives but I did not figure out how to apply it.

The actually clippy lint didn't make a whole lot of sense to me as it seems to be focused on the mutability of the Arc/Rc's elements, which doesn't seem to apply here. From my reading of this code and the other callsites, the use case of using Arc<String> is not mutability of the contained String but rather cheaply copying it around.

Using Arc<str> doesn't make sense as the actual String is allocated at runtime (it is the formatted version of an explain plan)

[Dandandan]

There is some discussion about why it can make sense to use Arc<str> over Arc<String>:
https://users.rust-lang.org/t/arc-string-vs-arc-str/30571

of course, difference is minimal, only saving a bit of indirection/some bytes.

You can use into to convert a String or &str into a Arc<str> or Rc<str>
https://doc.rust-lang.org/std/sync/struct.Arc.html#impl-From%3CString%3E

Example:
https://play.rust-lang.org/?version=stable&mode=debug&edition=2018&gist=eb6db938ae03b001edca59aba1512d33

[codecov-io]

Codecov Report

Merging #8930 (5788152) into master (d65ba4e) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master    #8930   +/-   ##
=======================================
  Coverage   83.25%   83.25%           
=======================================
  Files         196      196           
  Lines       48116    48116           
=======================================
  Hits        40059    40059           
  Misses       8057     8057           

Impacted Files	Coverage Δ
rust/datafusion/src/logical_plan/expr.rs	76.76% <ø> (ø)
rust/datafusion/src/logical_plan/plan.rs	87.93% <ø> (ø)
rust/parquet/src/util/cursor.rs	83.18% <ø> (ø)
rust/parquet/src/util/memory.rs	89.57% <ø> (ø)
rust/arrow/src/array/array_struct.rs	88.68% <100.00%> (ø)

---

Continue to review full report at Codecov.

Legend - Click here to learn more
Δ = absolute <relative> (impact), ø = not affected, ? = missing data
Powered by Codecov. Last update d65ba4e...5788152. Read the comment docs.

[jorgecarleitao]

LGTM. Thanks for taking the time to address this. Good stuff!