[SPARK-23769][Core]Remove comments that unnecessarily disable Scalastyle check

[arucard21]

What changes were proposed in this pull request?

We re-enabled the Scalastyle checker on a line of code. It was previously disabled, but it does not violate any of the rules. So there's no reason to disable the Scalastyle checker here.

How was this patch tested?

We tested this by running build/mvn scalastyle:check after removing the comments that disable the checker. This check passed with no errors or warnings for Spark Core

[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building Spark Project Core 2.4.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] --- scalastyle-maven-plugin:1.0.0:check (default-cli) @ spark-core_2.11 ---
Saving to outputFile=<path to local dir>/spark/core/target/scalastyle-output.xml
Processed 485 file(s)
Found 0 errors
Found 0 warnings
Found 0 infos

We did not run all tests (with dev/run-tests) since this Scalastyle check seemed sufficient.

Co-contributors:

@chialun-yeh
@Hrayo712
@vpourquie

[HyukjinKwon]

Minor change does't need a JIRA though. Mind checking if there are similar instances while we are here?

[HyukjinKwon]

Also, I believe more correct way is ./dev/lint-scala

[arucard21]

@HyukjinKwon I just ran ./dev/lint-scala as well and the result is Scalastyle checks passed.

As I mentioned in the JIRA issue, we looked at all the instances of scalastyle:off comments in spark/core/src/main/scala (so only the production code of the Core component of Spark). This is the only one where we noticed that disabling the Scalastyle checker was entirely unnecessary.

But we found another instance where it would be very easy to fix (even for beginners like us), so I'll create a PR for that as well. Since you said a minor change doesn't need a JIRA, I'll create the pull request only.

[HyukjinKwon]

That's fine. Let's invlove another insrance here.

[HyukjinKwon]

ok to teat

[arucard21]

@HyukjinKwon I had actually already created a separate branch for the other fix and was already creating a separate PR for it. So the other fix is in #20882.

I also think that the typo in your previous comment may have caused Jenkins to miss the keyword(s) to correctly detect it.

[HyukjinKwon]

ok to test

[HyukjinKwon]

let's include that change here.

[arucard21]

let's include that change here.

OK, I'll push the change in a few minutes. Should I close the other PR then?

[HyukjinKwon]

yea please

[arucard21]

Just pushed another fix for Scalastyle code checking. It just replaces a URL with a shortened version so we don't violate the max line length. Also tested with ./dev/lint-scala and closed the other PR.

@HyukjinKwon Thanks for your help with this. I really appreciate it.

[SparkQA]

Test build #88526 has finished for PR 20880 at commit de5c33a.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[SparkQA]

Test build #88525 has finished for PR 20880 at commit b6088e2.

• This patch passes all tests.
• This patch merges cleanly.
• This patch adds no public classes.

[jiangxb1987]

LGTM

[HyukjinKwon]

Merged to master and branch-2.3.