FIX: Exception error for multiple design (#5937)

Co-authored-by: pyansys-ci-bot <92810346+pyansys-ci-bot@users.noreply.github.com>

Author: ramin4667

doc/changelog.d/5937.fixed.md

@@ -0,0 +1 @@
+Exception error for multiple design

src/ansys/aedt/core/filtersolutions.py

@@ -22,6 +22,8 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+import warnings
+
 from ansys.aedt.core import settings
 import ansys.aedt.core.filtersolutions_core
 from ansys.aedt.core.filtersolutions_core.attributes import Attributes
@@ -45,11 +47,19 @@
 
 
 class FilterDesignBase:
-    """Provides the `FilterSolutions` main parameters applicable for all design types.
-    This class has access to ideal filter attributes and calculated output parameters.
-    """
+    """Provides the `FilterSolutions` main parameters applicable for all design types."""
+
+    _active_design = None
 
     def __init__(self, version=None):
+        if FilterDesignBase._active_design:
+            warnings.warn(
+                "FilterSolutions API currently supports only one design at a time. \n"
+                "Opening a new design will overwrite the existing design with default values.",
+                UserWarning,
+            )
+            FilterDesignBase._active_design.close()
+        FilterDesignBase._active_design = self
         self.version = version if version else settings.aedt_version
         ansys.aedt.core.filtersolutions_core._dll_interface(version)
         self.attributes = Attributes()
@@ -59,6 +69,33 @@ def __init__(self, version=None):
         self.transmission_zeros_bandwidth = TransmissionZeros(TableFormat.BANDWIDTH)
         self.export_to_aedt = ExportToAedt()
 
+    def close(self):
+        """Closes the current design and clears the active design."""
+        if FilterDesignBase._active_design == self:
+            print(f"Closing design: {self}")
+            self._cleanup_resources()
+            FilterDesignBase._active_design = None
+
+    def _cleanup_resources(self):
+        """Perform cleanup operations for the design."""
+        print("Cleaning up resources...")
+        self.attributes = None
+        self.ideal_response = None
+        self.graph_setup = None
+        self.transmission_zeros_ratio = None
+        self.transmission_zeros_bandwidth = None
+        self.export_to_aedt = None
+        self.source_impedance_table = None
+        self.load_impedance_table = None
+        self.multiple_bands_table = None
+        self.optimization_goals_table = None
+        self.topology = None
+        self.parasitics = None
+        self.leads_and_nodes = None
+        self.substrate = None
+        self.geometry = None
+        self.radial = None
+
 
 class LumpedDesign(FilterDesignBase):
     """Provides the `FilterSolutions` application interface for lumped filter designs.

tests/system/solvers/test_45_FilterSolutions/test_filter/test_attributes.py

@@ -22,6 +22,7 @@
 # OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 # SOFTWARE.
 
+import ansys.aedt.core.filtersolutions
 from ansys.aedt.core.filtersolutions_core.attributes import BesselRipplePercentage
 from ansys.aedt.core.filtersolutions_core.attributes import DiplexerType
 from ansys.aedt.core.filtersolutions_core.attributes import FilterClass
@@ -50,6 +51,24 @@
 @pytest.mark.skipif(is_linux, reason="FilterSolutions API is not supported on Linux.")
 @pytest.mark.skipif(config["desktopVersion"] < "2025.1", reason="Skipped on versions earlier than 2025.1")
 class TestClass:
+    def test_multiple_designs(self, lumped_design):
+        lumped_design.attributes.filter_class = FilterClass.BAND_PASS
+        assert lumped_design.attributes.filter_class == FilterClass.BAND_PASS
+        lumped_design.attributes.filter_type = FilterType.ELLIPTIC
+        assert lumped_design.attributes.filter_type == FilterType.ELLIPTIC
+        lumped_design.attributes.filter_order = 8
+        assert lumped_design.attributes.filter_order == 8
+        with pytest.warns(
+            UserWarning,
+            match="FilterSolutions API currently supports only one design at a time. \n"
+            "Opening a new design will overwrite the existing design with default values.",
+        ):
+            new_lumped_design = ansys.aedt.core.filtersolutions.LumpedDesign()
+        new_lumped_design = ansys.aedt.core.filtersolutions.LumpedDesign()
+        assert new_lumped_design.attributes.filter_class == FilterClass.LOW_PASS
+        assert new_lumped_design.attributes.filter_type == FilterType.BUTTERWORTH
+        assert new_lumped_design.attributes.filter_order == 5
+
     def test_filter_type(self, lumped_design):
         assert lumped_design.attributes.filter_type == FilterType.BUTTERWORTH
         assert hasattr(FilterType, "CHEBY") is False

tests/system/solvers/test_45_FilterSolutions/test_raise_error.py

@@ -36,3 +36,23 @@ def test_raise_error(self, lumped_design):
         with pytest.raises(RuntimeError) as info:
             lumped_design.transmission_zeros_ratio.row(0)
         assert info.value.args[0] == test_transmission_zeros.TestClass.no_transmission_zero_msg
+
+    @pytest.mark.skipif(config["desktopVersion"] < "2025.2", reason="Skipped on versions earlier than 2025.2")
+    def test_close_lumped_design(self, lumped_design):
+        lumped_design.close()
+        for attr_name in dir(lumped_design):
+            if attr_name.startswith("_") or callable(getattr(lumped_design, attr_name)):
+                continue
+            if attr_name in ["version"]:
+                continue
+            assert getattr(lumped_design, attr_name) is None
+
+    @pytest.mark.skipif(config["desktopVersion"] < "2025.2", reason="Skipped on versions earlier than 2025.2")
+    def test_close_distributed_design(self, distributed_design):
+        distributed_design.close()
+        for attr_name in dir(distributed_design):
+            if attr_name.startswith("_") or callable(getattr(distributed_design, attr_name)):
+                continue
+            if attr_name in ["version"]:
+                continue
+            assert getattr(distributed_design, attr_name) is None