Fix Diagnostics performance log hint from HealthMonitor

[JamesHazelcast]

It appears the log hint boolean check is inverted - currently the hint is only shown if diagnostics are already enabled; it should be the other way around.

[gbarnett-hz]

That seems confusing.

Small nitpick: maybe add test case to verify the log is presented only once when the initial state is false for hazelcast.diagnostics.enabled?

[pveentjer]

I'm not crazy about testing logging output. So I would not go for adding such a test.

[gbarnett-hz]

I'm not crazy about testing logging output. So I would not go for adding such a test.

Me too; but not on the output: the invocation given that the negation in multiple points made the data flow so confusing. Would have helped any future refactoring.

[JackPGreen]

I'm not crazy about testing logging output. So I would not go for adding such a test.

Me too; but not on the output: the invocation given that the negation in multiple points made the data flow so confusing. Would have helped any future refactoring.

I agree a test would be nice - it would’ve avoided this defect - but you’d need to decouple the check from the actual logger to assert the behaviour. And that’s quite a lot of overhead.

[pveentjer]

And you need to be able to control the logger which isn't always possible (or desirable) because it can make the code a lot more complex and that often isn't worth it.

[gbarnett-hz]

Indeed, depends on context. The only thing that (and as I noted it was a 'minor nitpick') adding a test would do is clarify the side effect of the entirely confusing boolean logic.