+1 thanks for this effort!
On 2023/12/21 21:22:54 Alex Petrov wrote: > Hey folks, > > I am mostly done with a patch that brings Harry in-tree [1]. I will trigger > one more CI run overnight, and my intention was to merge it some time soon, > but I wanted to give a fair warning here, since this is a relatively large > patch. > > Good news for everyone that it: > a) touches no production code whatsoever. Only test (in-jvm dtest namely) > code that was using Harry already. > b) the only tests that are changed are ones that used a duplicate version > of placement simulator we had both for testing TCM, and in Harry > c) in addition, I have converted 3 existing TCM tests to a new API to have > some base for examples/usage. > > Since we were effectively relying on this code for a while now, and the > intention now is to converge to: > a) fewer different generators, and have a shareable version of generators > for everyone to use accross the base > b) a testing tool that can be useful for both trivial cases, and complex > scenarios > myself and many other Cassandra contributors have expressed an opinion that > bringing Harry in-tree will be highly benefitial. > > I strongly believe that bringing Harry in-tree will help to lower the barrier > for fuzz test and simplify co-development of Cassandra and Harry. Previously, > it has been rather difficult to debug edge cases because I had to either > re-compile an in-jvm dtest jar and bring it to Harry, or re-compile a Harry > jar and bring it to Cassandra, which is both tedious and time consuming. > Moreover, I believe we have missed at very least one RT regression [2] > because Harry was not in-tree, as its tests would've caught the issue even > with the model that existed. > > For other recently found issues, I think having Harry in-tree would have > substantially lowered a turnaround time, and allowed me to share repros with > developers of corresponding features much quicker. > > I do expect a slight learning curve for Harry, but my intention is to build a > web of simple tests (worked on some of them yesterday after conversation with > David already), which can follow the in-jvm-dtest pattern of > find-similar-test / copy / modify. There's already copious documentation, so > I do not believe not having docs for Harry was ever an issue, since there > have been plenty. > > You all are aware of my dedication to testing and quality of Apache > Cassandra, and I hope you also see the benefits of having a model checker > in-tree. > > Thank you and happy upcoming holidays, > --Alex > > [1] https://issues.apache.org/jira/browse/CASSANDRA-19210 > [2] https://issues.apache.org/jira/browse/CASSANDRA-18932 >
