- Language: Java
- Rule: java:S6395 “Non-capturing groups without quantifier should not be used”
- SonarLint 9.1.0.81411 under Eclipse 4.30 (2023-12)
The rule wrongly raises an issue when non-capturing groups that (re)set flags are used (if the same group without setting flags would also raise it). Such groups can be semantically significant and their presence might be required (say, in String.split(String), since flags can’t otherwise be passed to the pattern).
"fooBar".split("(?i:b)"); is wrongly flagged.
For comparison, "fooBar".split("(?i)b") is not flagged, and "fooBar".split("(?:b)") is flagged, which is the expected behavior in both cases. Note that they have different semantics than the above example.