Update to SimulationMap type (#2753)

* Just renaming only

* Tests and API stable now

* Stable

* Tests passing

Author: daquinteroflex

GroundedCPWViaFence.py

@@ -0,0 +1,51 @@
+from __future__ import annotations
+
+import collections.abc
+
+import pydantic.v1 as pydantic
+import pytest
+
+from tidy3d import SimulationMap
+
+from ..utils import SAMPLE_SIMULATIONS
+
+# Reusable test constants
+SIM_MAP_DATA = {
+    "sim_A": SAMPLE_SIMULATIONS["full_fdtd"],
+    "sim_B": SAMPLE_SIMULATIONS["full_fdtd"].updated_copy(run_time=2e-12),
+}
+
+
+def make_simulation_map() -> SimulationMap:
+    """Factory function to create a standard SimulationMap instance."""
+    return SimulationMap(keys=tuple(SIM_MAP_DATA.keys()), values=tuple(SIM_MAP_DATA.values()))
+
+
+def test_simulation_map_creation():
+    """Tests successful creation and basic properties of a SimulationMap."""
+    s_map = make_simulation_map()
+    assert isinstance(s_map, collections.abc.Mapping)
+    assert len(s_map) == len(SIM_MAP_DATA)
+    assert s_map["sim_A"] == SIM_MAP_DATA["sim_A"]
+    assert list(s_map.keys()) == list(SIM_MAP_DATA.keys())
+
+
+def test_simulation_map_invalid_type_raises_error():
+    """Tests that a ValidationError is raised for incorrect value types."""
+    invalid_data = {"sim_A": "not a simulation"}
+    with pytest.raises(pydantic.ValidationError):
+        SimulationMap(keys=tuple(invalid_data.keys()), values=tuple(invalid_data.values()))
+
+
+def test_simulation_map_getitem_success():
+    """Tests successful retrieval of a simulation by its string key."""
+    s_map = make_simulation_map()
+    assert s_map["sim_A"] == SIM_MAP_DATA["sim_A"]
+    assert s_map["sim_B"] == SIM_MAP_DATA["sim_B"]
+
+
+def test_simulation_map_getitem_key_error():
+    """Tests that a KeyError is raised when retrieving a non-existent key."""
+    s_map = make_simulation_map()
+    with pytest.raises(KeyError):
+        _ = s_map["not_a_real_key"]