AssertJ Refaster rules for `Iterator#hasNext()`

[knutwannheden]

Running the JUnitToAssertJRules across some code I noticed that AssertThatIsTrue and AssertThatIsFalse transformed some JUnit assertTrue() and assertFalse() calls:

It seems like it would be a nice addition to have specific rules calling AbstractIteratorAssert#hasNext() and AbstractIteratorAssert#isExhausted() instead.

The example was found in hibernate/hibernate-tools: https://github.com/hibernate/hibernate-tools/blob/10431fc27866d295be9d2062ffdc9b1cd9099c16/jbt/src/test/java/org/hibernate/tool/orm/jbt/util/NativeConfigurationTest.java#L242-L247

[knutwannheden]

I suppose there would be a lot more interesting rules of this type that could be added. String#contains(CharSequence) comes to mind.

[knutwannheden]

Adding these type of rules to AssertJRules probably makes more sense.

[timtebeek]

In general this is a nice overview of recommended replacements for better assertions:
https://next.sonarqube.com/sonarqube/coding_rules?open=java%3AS5838&rule_key=java%3AS5838

On our side we're tackling these through

• Chained AssertJ assertions should be simplified to the corresponding dedicated assertion openrewrite/rewrite-testing-frameworks#556

But could be nice to have these covered with Refaster rules as well, for that early feedback.

[Stephan202]

I forgot about this issue. Some of the rules mentioned here I added in #1479, but there's more to do, so will keep it open for now.

[Stephan202]

I now also filed #1487. This still doesn't cover all of Sonar's S5838 rule, so will keep the issue open for a while longer.

[Stephan202]

For future reference, S5838 is implemented by this code, with rule defined here.