[tests] more test coverage

meanas/test/test_fdfd_farfield.py

@@ -0,0 +1,74 @@
+import numpy
+import pytest
+
+from ..fdfd import farfield
+
+
+NEAR_SHAPE = (2, 3)
+E_NEAR = [numpy.zeros(NEAR_SHAPE, dtype=complex), numpy.zeros(NEAR_SHAPE, dtype=complex)]
+H_NEAR = [numpy.zeros(NEAR_SHAPE, dtype=complex), numpy.zeros(NEAR_SHAPE, dtype=complex)]
+
+
+def test_near_to_farfield_rejects_wrong_length_inputs() -> None:
+    with pytest.raises(Exception, match='E_near must be a length-2 list'):
+        farfield.near_to_farfield(E_NEAR[:1], H_NEAR, dx=0.2, dy=0.3)
+
+    with pytest.raises(Exception, match='H_near must be a length-2 list'):
+        farfield.near_to_farfield(E_NEAR, H_NEAR[:1], dx=0.2, dy=0.3)
+
+
+def test_near_to_farfield_rejects_mismatched_shapes() -> None:
+    bad_h_near = [H_NEAR[0], numpy.zeros((2, 4), dtype=complex)]
+
+    with pytest.raises(Exception, match='All fields must be the same shape'):
+        farfield.near_to_farfield(E_NEAR, bad_h_near, dx=0.2, dy=0.3)
+
+
+def test_near_to_farfield_uses_default_and_scalar_padding_shapes() -> None:
+    default_result = farfield.near_to_farfield(E_NEAR, H_NEAR, dx=0.2, dy=0.3)
+    scalar_result = farfield.near_to_farfield(E_NEAR, H_NEAR, dx=0.2, dy=0.3, padded_size=8)
+
+    assert default_result['E'][0].shape == (2, 4)
+    assert default_result['H'][0].shape == (2, 4)
+    assert scalar_result['E'][0].shape == (8, 8)
+    assert scalar_result['H'][0].shape == (8, 8)
+
+
+def test_far_to_nearfield_rejects_wrong_length_inputs() -> None:
+    ff = farfield.near_to_farfield(E_NEAR, H_NEAR, dx=0.2, dy=0.3, padded_size=8)
+
+    with pytest.raises(Exception, match='E_far must be a length-2 list'):
+        farfield.far_to_nearfield(ff['E'][:1], ff['H'], ff['dkx'], ff['dky'])
+
+    with pytest.raises(Exception, match='H_far must be a length-2 list'):
+        farfield.far_to_nearfield(ff['E'], ff['H'][:1], ff['dkx'], ff['dky'])
+
+
+def test_far_to_nearfield_rejects_mismatched_shapes() -> None:
+    ff = farfield.near_to_farfield(E_NEAR, H_NEAR, dx=0.2, dy=0.3, padded_size=8)
+    bad_h_far = [ff['H'][0], numpy.zeros((8, 4), dtype=complex)]
+
+    with pytest.raises(Exception, match='All fields must be the same shape'):
+        farfield.far_to_nearfield(ff['E'], bad_h_far, ff['dkx'], ff['dky'])
+
+
+def test_far_to_nearfield_uses_default_and_scalar_padding_shapes() -> None:
+    ff = farfield.near_to_farfield(E_NEAR, H_NEAR, dx=0.2, dy=0.3, padded_size=8)
+    default_result = farfield.far_to_nearfield(
+        [field.copy() for field in ff['E']],
+        [field.copy() for field in ff['H']],
+        ff['dkx'],
+        ff['dky'],
+    )
+    scalar_result = farfield.far_to_nearfield(
+        [field.copy() for field in ff['E']],
+        [field.copy() for field in ff['H']],
+        ff['dkx'],
+        ff['dky'],
+        padded_size=4,
+    )
+
+    assert default_result['E'][0].shape == (8, 8)
+    assert default_result['H'][0].shape == (8, 8)
+    assert scalar_result['E'][0].shape == (4, 4)
+    assert scalar_result['H'][0].shape == (4, 4)