See SearchTranslationUnit(SearchSettings, TranslationUnit). The default implementation returns SearchSegment(SearchSettings, Segment), called for the source segment of translationUnit.

Note that a result is computed and returned although SupportsSearchForTranslationUnits is false by default.

See SearchTranslationUnit(SearchSettings, SubsegmentSearchSettings, SubsegmentSearchCondition, TranslationUnit). The default implementation simply returns null.