Controller's unavailable, so I'm testing inspection parsing offline. Every mock method returns true. How do I make this catch an actual interface mistake instead of applauding every screen?
A substitute that always succeeds can hide the same problems as an incomplete inspection checklist. Use the documented return shapes for the version you're targeting, plus failures and malformed replies. Keep this about software behaviour, not simulated robot performance.
Found one already: screen treats any nonempty container as success. I'm adding the documented failure shape, then a good response followed by failure so stale values don't sneak through.
Also make unexpected calls fail visibly in the mock. Otherwise a misspelled method or wrong argument list can still get a cheerful true without exercising the interface you meant to use.
Will you check the revised display with its users as well? A technically correct unknown state still needs to be distinguishable from a fresh inspection result.