SOLR-17156: introducing RandomNoReverseMergePolicyFactory

[mkhludnev]

healing BJQParserTest

https://issues.apache.org/jira/browse/SOLR-17156

[mkhludnev]

It needs to be spread across other block join tests as well.

[janhoy]

Cool!

[mkhludnev]

The scope has blown up. Are there other tests rely on block alignment?

[dsmiley]

No; please use SystemPropertiesRestoreRule instead. See its constructor that takes the key and value. No need to add BeforeClass/AfterClass logic to all these tests.
Hopefully no need to bother with touching test infrastructure (e.g. SolrTestCase).

[mkhludnev]

@dsmiley thanks for the guidance. I'll check it out.

[mkhludnev]

SystemPropertiesRestoreRule instead. See its constructor that takes the key and value.

I'm ok with this proposal @dsmiley. But I can't find any usage of two args constructor, so far all tests use systemSetPropertySolrTestsMergePolicyFactory. As far as I understand SystemPropertiesRestoreRule rule already applied and restores props thus, I don't need to bother about restoring in @AfterClass - ok.
Then if I use this rule, I need to copy-paste prop name from systemSetPropertySolrTestsMergePolicyFactory that doesn't seem good for me. if this bi-arg constructor works, should I use RuleChain or just @Rule?

Note: I changed SolrTestCase just to fix its' subclasses which don't inherit SolrTestCase4J.

[dsmiley]

if this bi-arg constructor works, should I use RuleChain or just @rule

RuleChain is for more compactly listing many rules and/or if the ordering is important and should be clear. Here, I think simply @ClassRule for an entire test source file (aka test suite).

Then if I use this rule, I need to copy-paste prop name from systemSetPropertySolrTestsMergePolicyFactory that doesn't seem good for me.

Could define the Map.of(...,...) constant in SolrTestCase. This rule accepts a Map constructor. I personally don't care; string literals don't bother me. Some people seem religious about avoiding them. 🤷

[dsmiley]

Nice

[mkhludnev]

I think it's test only change, thus it doesn't deserves CHANGES entry