core: fix error when missing traction in engineering allowances

Signed-off-by: Eloi Charpentier <[email protected]>

Author: eckter

core/envelope-sim/src/main/java/fr/sncf/osrd/envelope_sim/overlays/EnvelopeAcceleration.java

@@ -4,6 +4,8 @@
 import fr.sncf.osrd.envelope_sim.Action;
 import fr.sncf.osrd.envelope_sim.EnvelopeSimContext;
 import fr.sncf.osrd.envelope_sim.TrainPhysicsIntegrator;
+import fr.sncf.osrd.reporting.exceptions.ErrorType;
+import fr.sncf.osrd.reporting.exceptions.OSRDError;
 
 public class EnvelopeAcceleration {
     /** Accelerate, storing the resulting steps into consumer */
@@ -22,7 +24,7 @@ public static void accelerate(
             position += step.positionDelta;
             speed = step.endSpeed;
             if (!consumer.addStep(position, speed, step.timeDelta)) break;
-            assert (step.positionDelta != 0.0);
+            if (step.positionDelta == 0.0) throw new OSRDError(ErrorType.ImpossibleSimulationError);
         }
     }
 }

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/engineering_allowance/EngineeringAllowanceManager.kt

@@ -96,7 +96,7 @@ class EngineeringAllowanceManager(
         val cachedSegments = backwardsSegments.cacheable()
         for ((i, segment) in cachedSegments.withIndex()) {
             val (newBeginSpeed, newTravelTime) =
-                segment.computeAccelSequenceFromEndSpeed(currentSpeed)
+                segment.computeAccelSequenceFromEndSpeed(currentSpeed) ?: break
 
             val travelTimeDiff = max(0.0, newTravelTime - segment.travelTime)
             currentAddedDelay += travelTimeDiff

core/src/main/kotlin/fr/sncf/osrd/stdcm/graph/engineering_allowance/SimulationSegment.kt

@@ -9,6 +9,8 @@ import fr.sncf.osrd.envelope.part.constraints.SpeedConstraint
 import fr.sncf.osrd.envelope_sim.EnvelopeProfile
 import fr.sncf.osrd.envelope_sim.overlays.EnvelopeAcceleration
 import fr.sncf.osrd.path.interfaces.TrainPath
+import fr.sncf.osrd.reporting.exceptions.ErrorType
+import fr.sncf.osrd.reporting.exceptions.OSRDError
 import fr.sncf.osrd.stdcm.graph.STDCMEdge
 import fr.sncf.osrd.stdcm.graph.STDCMGraph
 import fr.sncf.osrd.utils.units.Distance
@@ -26,7 +28,7 @@ data class SimulationSegment(
     val maxAddedDelay: Double,
     // Function to compute an acceleration over this segment. Can be dummy values for tests,
     // wrap a full simulation pipeline in normal processing.
-    val computeAccelSequenceFromEndSpeed: (Double) -> SummarizedSimulationResult,
+    val computeAccelSequenceFromEndSpeed: (Double) -> SummarizedSimulationResult?,
 ) {
     init {
         positive(beginTime)
@@ -109,7 +111,7 @@ private fun computeAcceleration(
     pathProperties: TrainPath,
     endSpeed: Double,
     graph: STDCMGraph,
-): SummarizedSimulationResult {
+): SummarizedSimulationResult? {
     // TODO: we could look into using const accelerations here as well instead of using
     // envelopes. We'd need to estimate the max slope for each segment.
     // It's a performance / accuracy tradeoff.
@@ -133,13 +135,18 @@ private fun computeAcceleration(
             SpeedConstraint(0.0, EnvelopePartConstraintType.FLOOR),
             PositionConstraint(0.0, pathProperties.getLength().meters),
         )
-    EnvelopeAcceleration.accelerate(
-        context,
-        pathProperties.getLength().meters,
-        endSpeed,
-        overlayBuilder,
-        -1.0,
-    )
+    try {
+        EnvelopeAcceleration.accelerate(
+            context,
+            pathProperties.getLength().meters,
+            endSpeed,
+            overlayBuilder,
+            -1.0,
+        )
+    } catch (e: OSRDError) {
+        if (e.osrdErrorType == ErrorType.ImpossibleSimulationError) return null
+        throw e
+    }
     val speedupPart = speedupPartBuilder.build()
     val envelope = Envelope.make(speedupPart)
     val newTime = scaleAllowanceTime(graph, envelope.totalTime, pathProperties.getLength().distance)