Create test_particle_in_field.py (#9)

* Create test_particle_in_field.py

* Create basic working test

* Add ChargedParticle test

.gitignore

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+output/
+__pycache__/
+.DS_Store
+.coverage

test_particle_in_field.py

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+"""Tests the EMWave and ChargedParticle PhysicsModules"""
+
+import pytest
+from turbopy import Simulation
+from particle_in_field import EMWave, ChargedParticle
+
+wave_data = {"amplitude": 10, "omega": 18}
+particle_data = {"position": 25, "pusher": "ForwardEuler"}
+
+
+@pytest.fixture(name="sim_example")
+def fixture():
+    """"Creates a Simulation object to be used as the owner of an
+    EMWave object and a ChargedParticle PhysicsModule for testing"""
+    input_data = {"Grid": {"N": 10, "min": 20, "max": 30},
+                  "PhysicsModules": {"EMWave": wave_data,
+                                     "ChargedParticle": particle_data},
+                  "Tools": {"ForwardEuler": {}},
+                  "Clock": {"start_time": 0, "end_time": 1, "num_steps": 2}}
+    sim = Simulation(input_data)
+    sim.prepare_simulation()
+    return sim
+
+
+def test_emwave(sim_example):
+    """Tests the EMWave PhysicsModule"""
+    em_example = EMWave(sim_example, wave_data)
+    assert isinstance(em_example, EMWave)
+    assert em_example.c == 2.998e8
+    assert em_example.E0 == wave_data["amplitude"]
+    assert em_example.omega == wave_data["omega"]
+    assert em_example.k == wave_data["omega"] / 2.998e8
+
+
+def test_chargedparticle(sim_example):
+    """Tests the ChargedParticle PhysicsModule"""
+    charged_example = ChargedParticle(sim_example, particle_data)
+    assert isinstance(charged_example, ChargedParticle)
+    assert charged_example.E is None
+    assert charged_example.x == particle_data["position"]