presto-main/src/main/java/io/prestosql/sql/analyzer/FeaturesConfig.java/FeaturesConfig/isSpillerSpillPathsConfiguredIfSpillEnabled
class FeaturesConfig:    @AssertTrue(message = SPILLER_SPILL_PATH + " must be configured when " + SPILL_ENABLED + " is set to true")
    public boolean isSpillerSpillPathsConfiguredIfSpillEnabled()
    {
        return !isSpillEnabled() || !spillerSpillPaths.isEmpty();
    }