[ZOOKEEPER-2266] Integrate JaCoCo Coverage Library

• Type: Improvement
• Status: Resolved
• Priority: Minor
• Resolution: Won't Fix
• Component/s: tests
• Labels: pull-request-available
• Flags: Patch
• Assignee: Norbert Kalmár
• Reporter: Akihiro Suda
• Created: 07/Sep/15 09:23
• Updated: 12/Oct/22 14:04
• Resolved: 12/Oct/22 14:04

Description

I would like to propose integration of JaCoCo coverage library with ZooKeeper.

Purposes

• To find poorly covered methods, and improve JUnit testcases to cover them
• To estimate causes of flaky testcases (e.g. ZOOKEEPER-2080, ZOOKEEPER-2252, ZOOKEEPER-1868) by comparing reports from succeeded experiments and failed ones (I'm recently interested in how we can systematically realize this.)

Advantages of JaCoCo

• Support recent JDKs (including JDK 8)
• Low overhead
• Released under EPL
  • Note: cobertura has been removed from the code base because it is released under GPL ( ZOOKEEPER-75, http://www.apache.org/legal/resolved.html#category-x )

Usage

$ ant test #(plus optionally, -Dtestcase=.. -Dtest.method=..)
$ ant jacoco-report
$ x-www-browser build/test/jacoco/reports/index.html &

Example: jacoco-report-example.zip

Possible Future Work

• Integrate to Jenkins buildbot so that we can check coverage after each of builds

Issue Links

• relates to: ZOOKEEPER-2294 Ant target generate-clover-reports is broken
• links to: GitHub Pull Request #1451