[coretl]

Allow the mock class to be chosen per device type anywhere in a device tree, including children that only exist after connect (PVI, Tango, Command).

Supersedes #1429, which lets init_devices choose mocks for the devices it creates but cannot reach children further down the tree.

Usage

with init_devices(mock={Motor: VeloAndAcclRespectingMotorMock}):
    motor = Motor("PREFIX:")             # gets VeloAndAcclRespectingMotorMock
    stage = ThingWithMotors("PREFIX:")   # so do its Motor children

ensure_connected(..., mock={...}) takes the same argument. Both validate mock at runtime and raise TypeError for a bad one; Device.connect is checked by static analysis only.

Behaviour changes

• init_devices(mock=...), ensure_connected(mock=...) and the new connect_devices take bool | Mapping[type[Device], bool | type[DeviceMock]], so you can mix real and mocked Devices anywhere in a tree (e.g. {Device: True, Motor: False}). An entry under Device is the default for the first level only. ensure_connected no longer accepts a DeviceMock instance.
• Device.connect(mock=...) takes bool | DeviceMock; a DeviceMock instance's mocked and mock_types decide the Device and its children.
• DeviceMock.__init__(name="", parent=None, mocked=True, *, mock_types=None). A real Device holds a DeviceMock too, so get_mock works on any connected Device and raises if its last connect has not succeeded.
• DeviceConnector.connect_mock and DeviceConnector.connect_real are replaced by one DeviceConnector.connect(device, mock, timeout, force_reconnect); overrides branch on mock.mocked and call super().connect(...). An out-of-tree connector that still overrides the old names is silently ignored, so its backend never connects: rename the override.
• Mocked connects are now cached like real ones. A second connect(mock=True) with the same choice keeps mock values and call records; pass force_reconnect=True to rebuild. Any connect that is not cached connects everything below it again.
• Children connect in parallel with the caller's timeout and force_reconnect, also under a mocked parent.
• The DeviceMock.connect hook now runs for Signals and Commands too.
• LazyMock is deprecated; use DeviceMock.

AI Disclaimer

The code and this description were generated with AI and reviewed/tweaked by the author.

[coretl]

Converting back to draft, I've got a simplified design in the works, I'll re-request review when it's ready...

[coretl]

@jwlodek this is now ready to review