docs: Update test docstrings to follow RocketPy NumPy style guidelines

tests/unit/motors/test_point_mass_motor.py

@@ -4,6 +4,11 @@
 
 
 def test_init_required_args():
+    """Tests that PointMassMotor initializes correctly with required arguments.
+
+    Verifies that the motor is properly instantiated and that basic properties
+    like dry_mass, propellant_initial_mass, and burn_time are correctly set.
+    """
     m = PointMassMotor(
         thrust_source=10, dry_mass=1.0, propellant_initial_mass=0.5, burn_time=1.2
     )
@@ -15,6 +20,12 @@ def test_init_required_args():
 
 
 def test_missing_required_args_raises():
+    """Tests that PointMassMotor raises errors for missing required arguments.
+
+    Verifies that ValueError is raised when propellant_initial_mass is None
+    or when burn_time is not provided with constant thrust. Also verifies
+    TypeError is raised for invalid thrust_source types.
+    """
     # TODO: in the future we would like to capture specific RocketPy Exceptions
     with pytest.raises(ValueError):
         PointMassMotor(10, 1.0, None, 1)
@@ -25,6 +36,11 @@ def test_missing_required_args_raises():
 
 
 def test_exhaustvelocity_and_totalmassflowrate():
+    """Tests that exhaust_velocity and total_mass_flow_rate return Function objects.
+
+    Verifies that both properties are callable functions with get_value method,
+    which is required for numerical evaluation during simulation.
+    """
     m = PointMassMotor(
         thrust_source=10, dry_mass=1.0, propellant_initial_mass=1.0, burn_time=2.0
     )
@@ -35,6 +51,11 @@ def test_exhaustvelocity_and_totalmassflowrate():
 
 
 def test_zero_inertias():
+    """Tests that all propellant inertia components are zero for point mass motor.
+
+    Verifies that propellant_I_11, propellant_I_22, and propellant_I_33 all
+    return zero, as expected for a point mass model without rotational dynamics.
+    """
     m = PointMassMotor(
         thrust_source=10, dry_mass=1.0, propellant_initial_mass=1.0, burn_time=2.0
     )
@@ -44,6 +65,11 @@ def test_zero_inertias():
 
 
 def test_callable_thrust():
+    """Tests that PointMassMotor accepts a callable function as thrust_source.
+
+    Verifies that when a lambda function is used for thrust_source, the motor
+    correctly evaluates thrust values at different times.
+    """
     m = PointMassMotor(
         thrust_source=lambda t: 100 * t,
         dry_mass=2,

tests/unit/rocket/test_point_mass_rocket.py

@@ -3,6 +3,11 @@
 
 
 def test_init_sets_basic_properties_correctly():
+    """Tests that PointMassRocket initializes with correct basic properties.
+
+    Verifies that radius, mass, motor assignment, and zero inertias are
+    correctly set when a PointMassRocket is created and a motor is added.
+    """
     motor = PointMassMotor(10, 1.0, 0.5, 1.0)
     rocket = PointMassRocket(
         radius=0.05,
@@ -19,7 +24,11 @@ def test_init_sets_basic_properties_correctly():
 
 
 def test_structural_and_total_mass():
-    """Test structural and total mass properties of point mass rocket."""
+    """Tests structural and total mass properties of PointMassRocket.
+
+    Verifies that the rocket's structural mass and total mass (including motor
+    dry mass and propellant) are calculated correctly at time t=0.
+    """
     motor = PointMassMotor(10, 1.0, 1.1, 2.0)
     rocket = PointMassRocket(
         radius=0.03,
@@ -37,7 +46,11 @@ def test_structural_and_total_mass():
 
 
 def test_add_motor_overwrites():
-    """Test that adding a motor overwrites the previous motor."""
+    """Tests that adding a new motor to PointMassRocket overwrites the previous motor.
+
+    Verifies that when add_motor is called multiple times, only the most
+    recently added motor is retained.
+    """
     motor1 = PointMassMotor(10, 1, 1.1, 2.0)
     motor2 = PointMassMotor(20, 2, 1.5, 3.0)
     rocket = PointMassRocket(0.02, 1.0, 0.0, 0.2, 0.5)

tests/unit/simulation/test_flight_3dof.py

@@ -8,11 +8,13 @@
 
 @pytest.fixture
 def point_mass_motor():
-    """Simple PointMassMotor for 3-DOF tests.
+    """Creates a simple PointMassMotor for 3-DOF flight tests.
 
     Returns
     -------
     rocketpy.PointMassMotor
+        A point mass motor with constant thrust of 10 N, 1.0 kg dry mass,
+        0.5 kg propellant mass, and 2.2 s burn time.
     """
     return PointMassMotor(
         thrust_source=10,
@@ -24,11 +26,18 @@ def point_mass_motor():
 
 @pytest.fixture
 def point_mass_rocket(point_mass_motor):
-    """Simple PointMassRocket for 3-DOF tests.
+    """Creates a simple PointMassRocket for 3-DOF flight tests.
+
+    Parameters
+    ----------
+    point_mass_motor : rocketpy.PointMassMotor
+        The motor to be added to the rocket.
 
     Returns
     -------
     rocketpy.PointMassRocket
+        A point mass rocket with 0.05 m radius, 2.0 kg mass, and the
+        provided motor attached at position 0.
     """
     rocket = PointMassRocket(
         radius=0.05,
@@ -44,7 +53,15 @@ def point_mass_rocket(point_mass_motor):
 def test_simulation_mode_sets_3dof_with_point_mass_rocket(
     example_plain_env, point_mass_rocket
 ):
-    """Test that simulation mode is correctly set to 3 DOF."""
+    """Tests that simulation mode is correctly set to 3 DOF for PointMassRocket.
+
+    Parameters
+    ----------
+    example_plain_env : rocketpy.Environment
+        A basic environment fixture for flight simulation.
+    point_mass_rocket : rocketpy.PointMassRocket
+        A point mass rocket fixture for 3-DOF simulation.
+    """
     flight = Flight(
         rocket=point_mass_rocket,
         environment=example_plain_env,
@@ -55,7 +72,18 @@ def test_simulation_mode_sets_3dof_with_point_mass_rocket(
 
 
 def test_3dof_simulation_mode_warning(example_plain_env, point_mass_rocket):
-    """Test that a warning is issued when 6 DOF is requested with PointMassRocket."""
+    """Tests that a warning is issued when 6 DOF mode is requested with PointMassRocket.
+
+    When a PointMassRocket is used with simulation_mode="6 DOF", the Flight
+    class should emit a UserWarning and automatically switch to 3 DOF mode.
+
+    Parameters
+    ----------
+    example_plain_env : rocketpy.Environment
+        A basic environment fixture for flight simulation.
+    point_mass_rocket : rocketpy.PointMassRocket
+        A point mass rocket fixture for 3-DOF simulation.
+    """
     with pytest.warns(UserWarning):
         flight = Flight(
             rocket=point_mass_rocket,
@@ -69,7 +97,18 @@ def test_3dof_simulation_mode_warning(example_plain_env, point_mass_rocket):
 def test_u_dot_generalized_3dof_returns_valid_result(
     example_plain_env, point_mass_rocket
 ):
-    """Test that 3-DOF equations of motion return valid results."""
+    """Tests that 3-DOF equations of motion return valid derivative results.
+
+    Verifies that the u_dot_generalized_3dof method returns a list or numpy
+    array representing the state derivative vector.
+
+    Parameters
+    ----------
+    example_plain_env : rocketpy.Environment
+        A basic environment fixture for flight simulation.
+    point_mass_rocket : rocketpy.PointMassRocket
+        A point mass rocket fixture for 3-DOF simulation.
+    """
     flight = Flight(
         rocket=point_mass_rocket,
         environment=example_plain_env,
@@ -82,7 +121,15 @@ def test_u_dot_generalized_3dof_returns_valid_result(
 
 
 def test_invalid_simulation_mode(example_plain_env, calisto):
-    """Test that invalid simulation mode raises ValueError."""
+    """Tests that invalid simulation mode raises ValueError.
+
+    Parameters
+    ----------
+    example_plain_env : rocketpy.Environment
+        A basic environment fixture for flight simulation.
+    calisto : rocketpy.Rocket
+        The Calisto rocket fixture from the test suite.
+    """
     with pytest.raises(ValueError):
         Flight(
             rocket=calisto,