Added basic test code for the profiled PID subsystem.

Author: cwstryker

tests/test_profiledpidsubsystem.py

@@ -0,0 +1,119 @@
+from types import MethodType
+from typing import Any
+
+import pytest
+from wpimath.controller import ProfiledPIDController, ProfiledPIDControllerRadians
+from wpimath.trajectory import TrapezoidProfile, TrapezoidProfileRadians
+
+from commands2 import ProfiledPIDSubsystem
+
+MAX_VELOCITY = 30  # Radians per second
+MAX_ACCELERATION = 500  # Radians per sec squared
+PID_KP = 50
+
+
+class EvalSubsystem(ProfiledPIDSubsystem):
+    def __init__(self, controller, state_factory):
+        self._state_factory = state_factory
+        super().__init__(controller, 0)
+
+
+def simple_use_output(self, output: float, setpoint: Any):
+    """A simple _useOutput method that saves the current state of the controller."""
+    self._output = output
+    self._setpoint = setpoint
+
+
+def simple_get_measurement(self) -> float:
+    """A simple _getMeasurement method that returns zero (frozen or stuck plant)."""
+    return 0.0
+
+
+controller_types = [
+    (
+        ProfiledPIDControllerRadians,
+        TrapezoidProfileRadians.Constraints,
+        TrapezoidProfileRadians.State,
+    ),
+    (ProfiledPIDController, TrapezoidProfile.Constraints, TrapezoidProfile.State),
+]
+controller_ids = ["radians", "dimensionless"]
+
+
+@pytest.fixture(params=controller_types, ids=controller_ids)
+def subsystem(request):
+    """
+    Fixture that returns an EvalSubsystem object for each type of controller.
+    """
+    controller, profile_factory, state_factory = request.param
+    profile = profile_factory(MAX_VELOCITY, MAX_ACCELERATION)
+    pid = controller(PID_KP, 0, 0, profile)
+    return EvalSubsystem(pid, state_factory)
+
+
+def test_profiled_pid_subsystem_init(subsystem):
+    """
+    Verify that the ProfiledPIDSubsystem can be initialized using
+    all supported profiled PID controller / trapezoid profile types.
+    """
+    assert isinstance(subsystem, EvalSubsystem)
+
+
+def test_profiled_pid_subsystem_not_implemented_get_measurement(subsystem):
+    """
+    Verify that the ProfiledPIDSubsystem._getMeasurement method
+    raises NotImplementedError.
+    """
+    with pytest.raises(NotImplementedError):
+        subsystem._getMeasurement()
+
+
+def test_profiled_pid_subsystem_not_implemented_use_output(subsystem):
+    """
+    Verify that the ProfiledPIDSubsystem._useOutput method raises
+    NotImplementedError.
+    """
+    with pytest.raises(NotImplementedError):
+        subsystem._useOutput(0, subsystem._state_factory())
+
+
+@pytest.mark.parametrize("use_float", [True, False])
+def test_profiled_pid_subsystem_set_goal(subsystem, use_float):
+    """
+    Verify that the ProfiledPIDSubsystem.setGoal method sets the goal.
+    """
+    if use_float:
+        subsystem.setGoal(1.0)
+        assert subsystem.getController().getGoal().position == 1.0
+        assert subsystem.getController().getGoal().velocity == 0.0
+    else:
+        subsystem.setGoal(subsystem._state_factory(1.0, 2.0))
+        assert subsystem.getController().getGoal().position == 1.0
+        assert subsystem.getController().getGoal().velocity == 2.0
+
+
+def test_profiled_pid_subsystem_enable_subsystem(subsystem):
+    """
+    Verify the subsystem can be enabled.
+    """
+    # Dynamically add _useOutput and _getMeasurement methods so the
+    # system can be enabled
+    setattr(subsystem, "_useOutput", MethodType(simple_use_output, subsystem))
+    setattr(subsystem, "_getMeasurement", MethodType(simple_get_measurement, subsystem))
+    # Enable the subsystem
+    subsystem.enable()
+    assert subsystem.isEnabled()
+
+
+def test_profiled_pid_subsystem_disable_subsystem(subsystem):
+    """
+    Verify the subsystem can be disabled.
+    """
+    # Dynamically add _useOutput and _getMeasurement methods so the
+    # system can be enabled
+    setattr(subsystem, "_useOutput", MethodType(simple_use_output, subsystem))
+    setattr(subsystem, "_getMeasurement", MethodType(simple_get_measurement, subsystem))
+    # Enable and then disable the subsystem
+    subsystem.enable()
+    subsystem.disable()
+    assert not subsystem.isEnabled()