FIX: raise Error if fail to craete terminal (#749)

Co-authored-by: ring630 <@gmail.com>

Author: hui-zhou-a

src/pyedb/dotnet/edb_core/cell/terminal/padstack_instance_terminal.py

@@ -84,8 +84,13 @@ def create(self, padstack_instance, name=None, layer=None, is_ref=False):
             isRef=is_ref,
         )
         terminal = PadstackInstanceTerminal(self._pedb, terminal)
-
-        return terminal if not terminal.is_null else False
+        if terminal.is_null:
+            msg = f"Failed to create terminal. "
+            if name in self._pedb.terminals:
+                msg += f"Terminal {name} already exists."
+            raise Exception(msg)
+        else:
+            return terminal
 
     def _get_parameters(self):
         """Gets the parameters of the padstack instance terminal."""

src/pyedb/dotnet/edb_core/cell/terminal/pingroup_terminal.py

@@ -56,7 +56,13 @@ def create(self, name, net_name, pin_group_name, is_ref=False):
             is_ref,
         )
         term = PinGroupTerminal(self._pedb, term)
-        return term if not term.is_null else False
+        if term.is_null:
+            msg = f"Failed to create terminal. "
+            if name in self._pedb.terminals:
+                msg += f"Terminal {name} already exists."
+            raise Exception(msg)
+        else:
+            return term
 
     def pin_group(self):
         """Gets the pin group the terminal refers to."""

src/pyedb/dotnet/edb_core/cell/terminal/point_terminal.py

@@ -59,4 +59,10 @@ def create(self, name, net, location, layer, is_ref=False):
             is_ref,
         )
         terminal = PointTerminal(self._pedb, terminal)
-        return terminal if not terminal.is_null else False
+        if terminal.is_null:
+            msg = f"Failed to create terminal. "
+            if name in self._pedb.terminals:
+                msg += f"Terminal {name} already exists."
+            raise Exception(msg)
+        else:
+            return terminal