Added tests of infinite numerical propagation.

src/test/java/org/orekit/propagation/numerical/FieldNumericalPropagatorTest.java

@@ -1726,6 +1726,30 @@ public class FieldNumericalPropagatorTest {
         }
     }
 
+    @Test
+    public void testInfinitePropagation() {
+        doTestInfinitePropagation(Decimal64Field.getInstance());
+    }
+
+    private <T extends CalculusFieldElement<T>>  void doTestInfinitePropagation(Field<T> field) {
+
+        Utils.setDataRoot("regular-data:atmosphere:potential/grgs-format");
+        GravityFieldFactory.addPotentialCoefficientsReader(new GRGSFormatReader("grim4s4_gr", true));
+
+        FieldNumericalPropagator<T> propagator = createPropagator(field);
+        propagator.setResetAtEnd(false);
+
+        // Stop condition
+        propagator.addEventDetector(new FieldDateDetector<T>(propagator.getInitialState().getDate().shiftedBy(60)));
+
+        // Propagate until the stop condition is reached
+        final FieldSpacecraftState<T> finalState =  propagator.propagate(FieldAbsoluteDate.getFutureInfinity(field));
+
+        // Check that the expected final state was reached
+        Assertions.assertEquals(60, finalState.getDate().durationFrom(propagator.getInitialState().getDate()).getReal());
+
+    }
+
     private static <T extends CalculusFieldElement<T>> void doTestShift(final FieldCartesianOrbit<T> orbit, final OrbitType orbitType,
                                                                     final PositionAngle angleType, final boolean withDerivatives,
                                                                     final double error60s, final double error120s,

src/test/java/org/orekit/propagation/numerical/NumericalPropagatorTest.java

@@ -1591,6 +1591,25 @@ public class NumericalPropagatorTest {
         }
     }
 
+    @Test
+    public void testInfinitePropagation() {
+
+        Utils.setDataRoot("regular-data:atmosphere:potential/grgs-format");
+        GravityFieldFactory.addPotentialCoefficientsReader(new GRGSFormatReader("grim4s4_gr", true));
+
+        final NumericalPropagator propag = createPropagator(initialState, OrbitType.KEPLERIAN, PositionAngle.TRUE);
+
+        // Stop condition
+        propag.addEventDetector(new DateDetector(initialState.getDate().shiftedBy(60)));
+
+        // Propagate until the stop condition is reached
+        final SpacecraftState finalState =  propag.propagate(AbsoluteDate.FUTURE_INFINITY);
+
+        // Check that the expected final state was reached
+        Assertions.assertEquals(60, finalState.getDate().durationFrom(initialState.getDate()));
+
+    }
+
     /** Record the dates treated by the handler.
      *  If they are out of an interval defined by a start and final date.
      */