Our sample-status display needs offline tests while the UR5e cell is unavailable. I deliberately misspelled a client call and the mock still returned success. Useful discovery, slightly insulting test suite. I have the applicable interface guide; I need the fake to enforce that contract rather than bless whatever the display happens to ask for
I'd make unsupported calls fail explicitly. On a previous display job we tested the readable response and forgot the failure that left the last green value on screen; a mock that always succeeds would have hidden that too.
Unsupported call now fails, and I've added the documented failed-read response. That exposed our display retaining the last available status with no stale indication. The value is useful history, but it looks current
Yes, the original observation time is already stored. The screen doesn't show it on this path. That's the edit, along with making the failed read visible
After that, try failure followed by recovery as well as recovery followed by failure. And leave the installed comparison outstanding until you can use the cell; getting the offline contract right is useful work on its own.