Function test_case_over_jsonb_columns

src/expr/src/interpret.rs:1929–1975

unsupported foreign call in numeric decoding

()

    #[mz_ore::test]
    #[cfg_attr(miri, ignore)] // unsupported foreign call in numeric decoding
    fn test_case_over_jsonb_columns() {
        // Regression test for PER-6: when CASE picks between two JSON columns whose
        // observed keys are disjoint, filter pushdown must not prune parts where
        // accessing a key only present in one branch might yield NULL in the other.
        let arena = RowArena::new();

        // `(CASE WHEN col0 THEN col1 ELSE col2 END) ->> 'y' IS NULL`
        let expr = MirScalarExpr::If {
            cond: Box::new(MirScalarExpr::column(0)),
            then: Box::new(MirScalarExpr::column(1)),
            els: Box::new(MirScalarExpr::column(2)),
        }
        .call_binary(
            MirScalarExpr::literal_ok(Datum::from("y"), ReprScalarType::String),
            JsonbGetStringStringify,
        )
        .call_unary(UnaryFunc::IsNull(IsNull));

        let relation = ReprRelationType::new(vec![
            ReprScalarType::Bool.nullable(false),
            ReprScalarType::Jsonb.nullable(false),
            ReprScalarType::Jsonb.nullable(false),
        ]);
        let mut interpreter = ColumnSpecs::new(&relation, &arena);
        interpreter.push_column(0, ResultSpec::value_between(Datum::False, Datum::True));
        interpreter.push_column(
            1,
            ResultSpec::map_spec(
                [("x".into(), ResultSpec::value(Datum::String("a")))]
                    .into_iter()
                    .collect(),
            ),
        );
        interpreter.push_column(
            2,
            ResultSpec::map_spec(
                [("y".into(), ResultSpec::value(Datum::String("b")))]
                    .into_iter()
                    .collect(),
            ),
        );

        let range_out = interpreter.expr(&expr).range;
        // When the CASE selects column 1, "y" is absent and `->> 'y'` yields NULL, so
        // `IS NULL` is True. The filter must not prune a part that could match.
        assert!(range_out.may_contain(Datum::True));
    }

    #[mz_ore::test]
    fn test_like() {