yangjie01 e3058ba17c [SPARK-33441][BUILD] Add unused-imports compilation check and remove all unused-imports ... ### What changes were proposed in this pull request? This pr add a new Scala compile arg to `pom.xml` to defense against new unused imports: - `-Ywarn-unused-import` for Scala 2.12 - `-Wconf:cat=unused-imports:e` for Scala 2.13 The other fIles change are remove all unused imports in Spark code ### Why are the changes needed? Cleanup code and add guarantee to defense against new unused imports ### Does this PR introduce _any_ user-facing change? No ### How was this patch tested? Pass the Jenkins or GitHub Action Closes #30351 from LuciferYang/remove-imports-core-module. Authored-by: yangjie01 <yangjie01@baidu.com> Signed-off-by: HyukjinKwon <gurwls223@apache.org>		2020-11-19 14:20:39 +09:00
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main	[SPARK-33441][BUILD] Add unused-imports compilation check and remove all unused-imports	2020-11-19 14:20:39 +09:00
test	[SPARK-32398][TESTS][CORE][STREAMING][SQL][ML] Update to scalatest 3.2.0 for Scala 2.13.3+	2020-07-23 16:20:17 -07:00