Julian>because we never had a test case that indicated how actual behavior differed from desired behavior
One of the tests has been included in Calcite sources for a while. Please refer to RexProgramFuzzyTest that I previously highlighted in "Search/Sarg: untested feature merged to the default branch" thread: https://lists.apache.org/thread.html/rce6e84d0e0cd5a227d64c9f670b43650833f43e0cbccb80e04f5e0cf%40%3Cdev.calcite.apache.org%3E Note: I believe "Sarg feature" should have been accompanied by the relevant additions to RefFuzzer, RexShrinker, and RexInterpreter as a part of the test coverage. Under the current implementation, users can't avoid/disable SEARCH/Sarg, and it is enabled by default, so the feature must come with tests. Vladimir
