Align PwrUSB power strip with the consolidated *Capability architecture

Problem: The PwrUSB family (PR #115) was branched before master consolidated all
capability mixins into hardwarelibrary/capabilities.py and renamed them
*Control -> *Capability. The clean merge left the power strip on the old
convention: a separate hardwarelibrary/powerstrips/capabilities.py with its own
Capability base and OutletSwitchingControl/DefaultOutletControl/
CurrentMeteringControl names, plus a duplicate capabilities()/hasCapability() on
PowerStripDevice. It imported and passed tests but was inconsistent with the
rest of the library, and mixins subclassed a different Capability base than the
canonical one (so isinstance against hardwarelibrary.capabilities found nothing).

Solution: Move the three mixins into the shared hardwarelibrary/capabilities.py
as OutletSwitchingCapability, DefaultOutletCapability, and
CurrentMeteringCapability (canonical Capability base); delete
powerstrips/capabilities.py. Reduce PowerStripDevice to a pure marker like
LaserSourceDevice, inheriting capabilities()/hasCapability() from
PhysicalDevice. Update pwrusb.py bases/imports, the package __init__ re-export,
tests, the skill doc, and the CHANGELOG entry accordingly.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

Author: dccote

.claude/skills/pyhardwarelibrary/SKILL.md

@@ -10,6 +10,12 @@ subclass with a uniform lifecycle and a small, predictable public API per family
 skill is for *using* devices to get work done (move, measure, set). To *write a new
 driver*, read `CLAUDE.md` and `README-4-New-device-coding-example.md` instead.
 
+**Developers: always pull `master` from origin before starting.** This repository evolves
+rapidly and its architecture shifts under you — capability mixins were recently renamed
+(`*Control` -> `*Capability`) and consolidated into a single `hardwarelibrary/capabilities.py`.
+Branch off an up-to-date `master` (`git pull` first) so you build against the current
+conventions, not a stale snapshot.
+
 **Use the primitives from `CommunicationPort` for all communications.** A driver's `do*`
 methods talk to hardware only through `self.port` — `writeData` / `readData` (and the
 `readString` / `writeString` / `writeStringReadMatch` helpers built on them). Do **not**
@@ -202,9 +208,9 @@ it declares.
 
 | Capability | Methods |
 |---|---|
-| `OutletSwitchingControl` | `turnOutletOn(n)`, `turnOutletOff(n)`, `setOutletState(n, isOn)`, `isOutletOn(n)`, `outletCount` |
-| `DefaultOutletControl` | `setOutletDefaultOn(n)`, `setOutletDefaultOff(n)`, `setOutletDefaultState(n, isOn)` |
-| `CurrentMeteringControl` | `current()` (A), `accumulatedCharge()` (Ah), `resetAccumulatedCharge()` |
+| `OutletSwitchingCapability` | `turnOutletOn(n)`, `turnOutletOff(n)`, `setOutletState(n, isOn)`, `isOutletOn(n)`, `outletCount` |
+| `DefaultOutletCapability` | `setOutletDefaultOn(n)`, `setOutletDefaultOff(n)`, `setOutletDefaultState(n, isOn)` |
+| `CurrentMeteringCapability` | `current()` (A), `accumulatedCharge()` (Ah), `resetAccumulatedCharge()` |
 
 ```python
 from hardwarelibrary.powerstrips import PwrUSBDevice

CHANGELOG.md

@@ -12,11 +12,12 @@ API changes can land even when the minor version is unchanged.
   power strip (USB HID `04d8:003f`, enumerates as "Simple HID Device Demo"). The
   family follows the interface-segregated capability-mixin pattern used by
   `sources/` and `daq/`: `PowerStripDevice` is a thin marker base over
-  `PhysicalDevice`, and behaviour comes from `OutletSwitchingControl`
+  `PhysicalDevice`, and behaviour comes from `OutletSwitchingCapability`
   (`turnOutletOn`/`turnOutletOff`/`setOutletState`/`isOutletOn`/`outletCount`,
-  outlets 1-based), `DefaultOutletControl` (per-outlet power-on default state),
-  and `CurrentMeteringControl` (`current()` in A, `accumulatedCharge()` in Ah,
-  `resetAccumulatedCharge()`). The strip speaks a single-byte HID report protocol
+  outlets 1-based), `DefaultOutletCapability` (per-outlet power-on default
+  state), and `CurrentMeteringCapability` (`current()` in A, `accumulatedCharge()`
+  in Ah, `resetAccumulatedCharge()`), all in the shared
+  `hardwarelibrary/capabilities.py`. The strip speaks a single-byte HID report protocol
   driven through a `HIDPort`; the protocol was reverse-engineered publicly and
   cross-checked against aarossig/pwrusbctl (Apache-2.0) and pwrusb.com, but the
   implementation is our own. Outlet state is cached on write because live

hardwarelibrary/capabilities.py

@@ -576,3 +576,102 @@ def getDigitalDirection(self, channel):
 
     def setDigitalDirection(self, channel):
         pass
+
+
+# ---------------------------------------------------------------------------
+# Power strip capabilities
+# ---------------------------------------------------------------------------
+
+
+class OutletSwitchingCapability(Capability):
+    """Switch individual outlets on and off and read their state.
+
+    Outlets are addressed by their physical label (1-based): the first
+    switchable outlet is outlet 1. Some strips also carry an always-on outlet
+    that is not switchable and is not counted here.
+    """
+
+    def turnOutletOn(self, outlet: int):
+        self.doSetOutletState(outlet, True)
+
+    def turnOutletOff(self, outlet: int):
+        self.doSetOutletState(outlet, False)
+
+    def setOutletState(self, outlet: int, isOn: bool):
+        self.doSetOutletState(outlet, isOn)
+
+    def isOutletOn(self, outlet: int) -> bool:
+        return self.doGetOutletState(outlet)
+
+    @property
+    def outletCount(self) -> int:
+        return self.doGetOutletCount()
+
+    @abstractmethod
+    def doSetOutletState(self, outlet: int, isOn: bool):
+        ...
+
+    @abstractmethod
+    def doGetOutletState(self, outlet: int) -> bool:
+        ...
+
+    @abstractmethod
+    def doGetOutletCount(self) -> int:
+        ...
+
+
+class DefaultOutletCapability(Capability):
+    """Set the power-on (boot) state of individual outlets.
+
+    Distinct from OutletSwitchingCapability: this configures the state each
+    outlet powers up in after the strip loses and regains mains power, not its
+    state right now.
+    """
+
+    def setOutletDefaultOn(self, outlet: int):
+        self.doSetOutletDefaultState(outlet, True)
+
+    def setOutletDefaultOff(self, outlet: int):
+        self.doSetOutletDefaultState(outlet, False)
+
+    def setOutletDefaultState(self, outlet: int, isOn: bool):
+        self.doSetOutletDefaultState(outlet, isOn)
+
+    @abstractmethod
+    def doSetOutletDefaultState(self, outlet: int, isOn: bool):
+        ...
+
+
+class CurrentMeteringCapability(Capability):
+    """Measure the strip's total current draw and accumulated charge.
+
+    Only metering-capable strips (e.g. the PowerUSB "Smart" model) implement
+    this; a driver mixes it in only when the hardware supports it. Values are in
+    SI units at this boundary: current in amperes, accumulated charge in
+    ampere-hours.
+    """
+
+    unit = "A"
+    isReadable = True
+    isWritable = False
+
+    def current(self) -> float:
+        return self.doGetCurrent()
+
+    def accumulatedCharge(self) -> float:
+        return self.doGetAccumulatedCharge()
+
+    def resetAccumulatedCharge(self):
+        self.doResetAccumulatedCharge()
+
+    @abstractmethod
+    def doGetCurrent(self) -> float:
+        ...
+
+    @abstractmethod
+    def doGetAccumulatedCharge(self) -> float:
+        ...
+
+    @abstractmethod
+    def doResetAccumulatedCharge(self):
+        ...

hardwarelibrary/powerstrips/__init__.py

@@ -1,6 +1,5 @@
-from .capabilities import (
-    Capability,
-    OutletSwitchingControl, DefaultOutletControl, CurrentMeteringControl,
+from hardwarelibrary.capabilities import (
+    OutletSwitchingCapability, DefaultOutletCapability, CurrentMeteringCapability,
 )
 from .powerstripdevice import PowerStripDevice
 from .pwrusb import PwrUSBDevice, DebugPwrUSBDevice, DebugPwrUSBPort

hardwarelibrary/powerstrips/capabilities.py

@@ -1,23 +1,9 @@
 from hardwarelibrary.physicaldevice import PhysicalDevice
-from hardwarelibrary.powerstrips.capabilities import Capability
 
 
 class PowerStripDevice(PhysicalDevice):
-    """Family marker base for controllable power strips (switched outlets).
-
-    A driver subclasses this and mixes in the capability classes from
-    capabilities.py (OutletSwitchingControl, DefaultOutletControl,
-    CurrentMeteringControl). The behaviour lives in the mixins; this base only
-    reports which capabilities a given driver actually implements.
-    """
-
-    def capabilities(self) -> list:
-        # The capability mixins, not the marker nor the device class itself
-        # (a driver is a Capability subclass too, but it is a PhysicalDevice).
-        return [klass for klass in type(self).__mro__
-                if issubclass(klass, Capability)
-                and klass is not Capability
-                and not issubclass(klass, PhysicalDevice)]
-
-    def hasCapability(self, capabilityClass) -> bool:
-        return isinstance(self, capabilityClass)
+    # A thin marker base for controllable power strips (switched outlets). The
+    # behavior comes from the *Capability mixins a driver combines with it;
+    # capability introspection (capabilities() / hasCapability()) is inherited
+    # from PhysicalDevice.
+    pass

hardwarelibrary/powerstrips/powerstripdevice.py

@@ -34,13 +34,13 @@
 from hardwarelibrary.communication.hidport import HIDPort
 from hardwarelibrary.communication.debugport import DebugPort
 from hardwarelibrary.powerstrips.powerstripdevice import PowerStripDevice
-from hardwarelibrary.powerstrips.capabilities import (
-    OutletSwitchingControl, DefaultOutletControl, CurrentMeteringControl,
+from hardwarelibrary.capabilities import (
+    OutletSwitchingCapability, DefaultOutletCapability, CurrentMeteringCapability,
 )
 
 
-class PwrUSBDevice(PowerStripDevice, OutletSwitchingControl,
-                   DefaultOutletControl, CurrentMeteringControl):
+class PwrUSBDevice(PowerStripDevice, OutletSwitchingCapability,
+                   DefaultOutletCapability, CurrentMeteringCapability):
     classIdVendor = 0x04d8
     classIdProduct = 0x003f
 

hardwarelibrary/powerstrips/pwrusb.py

@@ -4,7 +4,7 @@
 from hardwarelibrary.physicaldevice import PhysicalDevice
 from hardwarelibrary.powerstrips import (
     PwrUSBDevice, DebugPwrUSBDevice,
-    OutletSwitchingControl, DefaultOutletControl, CurrentMeteringControl,
+    OutletSwitchingCapability, DefaultOutletCapability, CurrentMeteringCapability,
 )
 
 
@@ -29,13 +29,13 @@ def testOutletCount(self):
 
     def testCapabilities(self):
         capabilities = self.device.capabilities()
-        self.assertIn(OutletSwitchingControl, capabilities)
-        self.assertIn(DefaultOutletControl, capabilities)
-        self.assertIn(CurrentMeteringControl, capabilities)
+        self.assertIn(OutletSwitchingCapability, capabilities)
+        self.assertIn(DefaultOutletCapability, capabilities)
+        self.assertIn(CurrentMeteringCapability, capabilities)
 
     def testHasCapability(self):
-        self.assertTrue(self.device.hasCapability(OutletSwitchingControl))
-        self.assertTrue(self.device.hasCapability(CurrentMeteringControl))
+        self.assertTrue(self.device.hasCapability(OutletSwitchingCapability))
+        self.assertTrue(self.device.hasCapability(CurrentMeteringCapability))
 
     def testAllOutletsStartOff(self):
         for outlet in (1, 2, 3):