Don't generate runway data for heliports.

Fixes https://github.com/dcs-liberation/dcs_liberation/issues/2710.

changelog.md

@@ -18,6 +18,7 @@ Saves from 6.x are not compatible with 7.0.
 
 * **[Data]** Fixed unit ID for the KS-19 AAA. KS-19 would not previously generate correctly in missions. A new game is required for this fix to take effect.
 * **[Flight Planning]** Automatic flight planning will no longer accidentally plan a recovery tanker instead of a theater refueling package. This fixes a potential crash during mission generation when opfor plans a refueling task at a sunk carrier. You'll need to skip the current turn to force opfor to replan their flights to get the fix.
+* **[Mission Generation]** Using heliports (airports without any runways) will no longer cause mission generation to fail.
 
 # 6.1.0
 

game/theater/controlpoint.py

@@ -878,6 +878,11 @@ class ControlPoint(MissionTarget, SidcDescribable, ABC):
     ) -> RunwayData:
         ...
 
+    def stub_runway_data(self) -> RunwayData:
+        return RunwayData(
+            self.full_name, runway_heading=Heading.from_degrees(0), runway_name=""
+        )
+
     @property
     def airdrome_id_for_landing(self) -> Optional[int]:
         return None
@@ -1138,6 +1143,14 @@ class Airfield(ControlPoint):
         conditions: Conditions,
         dynamic_runways: Dict[str, RunwayData],
     ) -> RunwayData:
+        if not self.airport.runways:
+            # Some airfields are heliports and don't have any runways. This isn't really
+            # the best fix, since we should still try to generate partial data for TACAN
+            # beacons, but it'll do for a bug fix, and the proper fix probably involves
+            # making heliports their own CP type.
+            # https://github.com/dcs-liberation/dcs_liberation/issues/2710
+            return self.stub_runway_data()
+
         assigner = RunwayAssigner(conditions)
         return assigner.get_preferred_runway(theater, self.airport)
 
@@ -1273,8 +1286,6 @@ class Carrier(NavalControlPoint):
         return SymbolSet.SEA_SURFACE, SeaSurfaceEntity.CARRIER
 
     def mission_types(self, for_player: bool) -> Iterator[FlightType]:
-        from game.ato import FlightType
-
         yield from super().mission_types(for_player)
         if self.is_friendly(for_player):
             yield from [
@@ -1379,9 +1390,7 @@ class OffMapSpawn(ControlPoint):
         dynamic_runways: Dict[str, RunwayData],
     ) -> RunwayData:
         logging.warning("TODO: Off map spawns have no runways.")
-        return RunwayData(
+        return self.stub_runway_data()
-            self.full_name, runway_heading=Heading.from_degrees(0), runway_name=""
-        )
 
     @property
     def runway_status(self) -> RunwayStatus:
@@ -1423,9 +1432,7 @@ class Fob(ControlPoint):
         dynamic_runways: Dict[str, RunwayData],
     ) -> RunwayData:
         logging.warning("TODO: FOBs have no runways.")
-        return RunwayData(
+        return self.stub_runway_data()
-            self.full_name, runway_heading=Heading.from_degrees(0), runway_name=""
-        )
 
     @property
     def runway_status(self) -> RunwayStatus: