[MAPREDUCE-7475] Fix non-idempotent unit tests

• Type: Bug
• Status: Resolved
• Priority: Minor
• Resolution: Fixed
• Affects Version/s: 3.4.0
• Fix Version/s: 3.5.0, 3.4.1
• Component/s: test
• Labels: pull-request-available

Environment

Ubuntu 22.04, Java 17

• Hadoop Flags: Reviewed
• Flags: Patch
• Assignee: Kaiyao Ke
• Reporter: Kaiyao Ke
• Created: 30/Apr/24 07:57
• Updated: 19/May/24 20:33
• Resolved: 19/May/24 20:33

Description

2 tests are not idempotent and fails upon repeated execution within the same JVM instance due to self-induced state pollution. Specifically, these tests try to make the directory TEST_ROOT_DIR and write to it. The tests do not clean up (remove) the directory after execution. Therefore, in the second execution, TEST_ROOT_DIR would already exist and the exception `Could not create test dir` would be thrown. Below are the 2 non-idempotent tests:

• org.apache.hadoop.mapred.TestOldCombinerGrouping.testCombiner
• org.apache.hadoop.mapreduce.TestNewCombinerGrouping.testCombiner

Issue Links

• links to: GitHub Pull Request #6785