Thanks for reviewing, Thawan.
his is minor but you can make Zab1_0Test class extends ClientBase and use its createTmpDir() method instead of creating tmpDir manually.
I'd rather do that in a separate jira, since it touches test cases that are unrelated to this issue.
Please update comments such as //Setup a database... and //Set the last.. to reflect what actually happen
Sure, will do.
Can we also test that the leader take snapshot when it have quorum of supported? Not sure if it is possible, but if we don't shutdown the leader at the end of the test and start a follower, then we should be able to test that code path.
I suppose you're talking about checking this:
+ * Take snapshot once it has a quorum of followers supporting
This snapshot is not strictly necessary for correctness, but it is convenient to do one at that point. I'd rather not extend the test case to verify it, since its addition does not affect correctness.