From 163804ecfbb2274f5ddde4ba501ab076b8ea9d5b Mon Sep 17 00:00:00 2001
From: dbochkov-flexcompute <daniil@flexcompute.com>
Date: Tue, 3 Dec 2024 10:31:35 -0600
Subject: [PATCH] pr comments

---
 tests/test_components/test_simulation.py |  2 +-
 tidy3d/components/simulation.py          | 19 ++++++++++---------
 2 files changed, 11 insertions(+), 10 deletions(-)

diff --git a/tests/test_components/test_simulation.py b/tests/test_components/test_simulation.py
index beab580acd..4c974d8117 100644
--- a/tests/test_components/test_simulation.py
+++ b/tests/test_components/test_simulation.py
@@ -3067,7 +3067,7 @@ def test_fixed_angle_sim():
         run_time=10 / fwidth,
     )
 
-    # assert sim.i
+    assert sim._is_fixed_angle
 
     with pytest.raises(pydantic.ValidationError):
         _ = sim.updated_copy(
diff --git a/tidy3d/components/simulation.py b/tidy3d/components/simulation.py
index cc420c7a23..dbe1b59dd0 100644
--- a/tidy3d/components/simulation.py
+++ b/tidy3d/components/simulation.py
@@ -2428,12 +2428,12 @@ def plane_wave_boundaries(cls, val, values):
                     num_bloch = sum(isinstance(bnd, BlochBoundary) for bnd in boundary)
                     if num_bloch > 0:
                         raise SetupError(
-                            "Fixed angle plane wave sources ('FixedAngleSpec' and `angle_theta != 0`) do "
+                            "Fixed angle plane wave sources ('FixedAngleSpec' and 'angle_theta' != 0) do "
                             f"not require the Bloch boundary along dimension {tan_dir}. "
                             "Either set the boundary conditions to 'Periodic' to proceed to simulate a plane "
                             "wave with frequency-independent propagation direction, or switch to "
-                            "'FixedInPlaneKSpec' specification to simulate a plane wave with "
-                            "frequency-dependent propagation direction."
+                            "'FixedInPlaneKSpec' specification to simulate a plane wave with a fixed "
+                            "in-plane Bloch vector (frequency-dependent propagation direction)."
                         )
                 else:
                     num_bloch = sum(isinstance(bnd, (Periodic, BlochBoundary)) for bnd in boundary)
@@ -2573,14 +2573,15 @@ def tfsf_with_symmetry(cls, val, values):
         return val
 
     @staticmethod
-    def _get_fixed_angle_sources(sources: Tuple[SourceType, ...]):
+    def _get_fixed_angle_sources(sources: Tuple[SourceType, ...]) -> Tuple[SourceType, ...]:
         """Get list of plane wave sources with ``FixedAngleSpec``."""
 
         return [
             source for source in sources if isinstance(source, PlaneWave) and source._is_fixed_angle
         ]
 
-    @pydantic.root_validator(skip_on_failure=True)
+    @pydantic.root_validator()
+    @skip_if_fields_missing(["sources", "structures", "medium", "monitors"], root=True)
     def check_fixed_angle_components(cls, values):
         """Error if a fixed-angle plane wave is combined with other sources
         or fully anisotropic mediums or gain mediums."""
@@ -3939,13 +3940,13 @@ def background_structure(self) -> Structure:
         return self.scene.background_structure
 
     @cached_property
-    def _fixed_angle_sources(self):
+    def _fixed_angle_sources(self) -> Tuple[SourceType, ...]:
         """List of plane wave sources with ``FixedAngleSpec``."""
         return self._get_fixed_angle_sources(self.sources)
 
     @cached_property
-    def _is_fixed_angle(self):
-        """List of plane wave sources with ``FixedAngleSpec``."""
+    def _is_fixed_angle(self) -> bool:
+        """Whether the simulation contains fixed angle sources."""
         return len(self._fixed_angle_sources) > 0
 
     # candidate for removal in 3.0
@@ -4373,7 +4374,7 @@ def plot_3d(self, width=800, height=800) -> None:
     """ Discretization """
 
     @cached_property
-    def _dt_fixed_angle_reduction_factor(self):
+    def _dt_fixed_angle_reduction_factor(self) -> float:
         """Reduction in time step due to plane wave source with ``FixedAngleSpec``."""
         if self._is_fixed_angle:
             theta = self._fixed_angle_sources[0].angle_theta