revise

Author: dmarek-flex

tidy3d/components/microwave/path_integrals/impedance_spec.py

@@ -6,7 +6,7 @@
 
 import pydantic.v1 as pd
 
-from tidy3d.components.base import Tidy3dBaseModel
+from tidy3d.components.base import Tidy3dBaseModel, skip_if_fields_missing
 from tidy3d.components.microwave.path_integrals.types import (
     CurrentPathSpecTypes,
     VoltagePathSpecTypes,
@@ -17,21 +17,21 @@
 class AutoImpedanceSpec(Tidy3dBaseModel):
     """Specification for fully automatic transmission line impedance computation.
 
-    This specification automatically calculates impedance by calculating the current associated
-    with each conductor that intersects the mode plane.
+    This specification automatically calculates impedance by current
+    paths based on the simulation geometry and conductors that intersect the mode plane.
+    No user-defined path specifications are required.
     """
 
 
 class CustomImpedanceSpec(Tidy3dBaseModel):
     """Specification for custom transmission line voltages and currents in mode solvers.
 
     The :class:`.CustomImpedanceSpec` class specifies how quantities related to transmission line
-    modes are computed. For example, it defines the paths for line integrals, which are used to
+    modes are computed. It defines the paths for line integrals, which are used to
     compute voltage, current, and characteristic impedance of the transmission line.
 
-    Users may supply their own voltage and current path specifications to control where these integrals
-    are evaluated. If neither voltage nor current specifications are provided, an automatic choice of
-    paths will be made based on the simulation geometry and context.
+    Users must supply at least one of voltage or current path specifications to control where these integrals
+    are evaluated. Both voltage_spec and current_spec cannot be ``None`` simultaneously.
     """
 
     voltage_spec: Optional[VoltagePathSpecTypes] = pd.Field(
@@ -51,9 +51,12 @@ class CustomImpedanceSpec(Tidy3dBaseModel):
     )
 
     @pd.validator("current_spec", always=True)
+    @skip_if_fields_missing(["voltage_spec"])
     def check_path_spec_combinations(cls, val, values):
-        """In order to define voltage/current/impedance, either a voltage or current path specification
-        must be provided.
+        """Validate that at least one of voltage_spec or current_spec is provided.
+
+        In order to define voltage/current/impedance, either a voltage or current path specification
+        must be provided. Both cannot be ``None`` simultaneously.
         """
 
         voltage_spec = values["voltage_spec"]

tidy3d/components/mode/mode_solver.py

@@ -1381,8 +1381,7 @@ def _make_path_integrals(
         )
 
     def _add_microwave_data(self, mode_solver_data: ModeSolverData) -> ModeSolverData:
-        """Calculate and add microwave data to ``mode_solver_data`` which uses the path specifications.
-        Note: this modifies ``mode_solver_data`` in-place."""
+        """Calculate and add microwave data to ``mode_solver_data`` which uses the path specifications."""
         voltage_integrals, current_integrals = self._make_path_integrals()
         # Need to operate on the full symmetry expanded fields
         mode_solver_data_expanded = mode_solver_data.symmetry_expanded_copy