Dataset access rules have a $KEY of their HLQ. To see the rule for SYS1.TEST, the following commands can be run in TSO ACF or ACFBATCH:
However, there could potentially be masked rules in play and the above may contain other rule entries for other SYS1 HLQ datasets (ie SYS1.PROCLIB). To view all rule entries and users that have access, either the ACCESS subcommand or the ACFRPTXR report can be used. They both behave similarly, so it is up to personal preference which one to use.
More detailed information for these options can be found here:
ACFRPTXR-The Cross-Reference Report
What is the CA-ACF2 ACCESS Command and how is it used?
ACFRPTXR output versus ACCESS Subcommand difference with ACF2 NEXTKEY Rules