Add day of month to day of week, X#Y syntax

Resolves jmrozanec#605

src/main/java/com/cronutils/mapper/CronMapper.java

@@ -29,7 +29,6 @@
 import com.cronutils.model.field.definition.FieldDefinition;
 import com.cronutils.model.field.expression.*;
 import com.cronutils.model.field.expression.visitor.FieldExpressionVisitorAdaptor;
-import com.cronutils.model.field.expression.visitor.ValueMappingFieldExpressionVisitor;
 import com.cronutils.model.field.value.FieldValue;
 import com.cronutils.model.field.value.IntegerFieldValue;
 import com.cronutils.model.field.value.SpecialChar;
@@ -286,12 +285,14 @@ static Function<CronField, CronField> dayOfWeekMapping(final DayOfWeekFieldDefin
             final FieldExpression expression = field.getExpression();
             FieldExpression dest = null;
             dest = expression.accept(new FieldExpressionVisitorAdaptor() {
+                @Override
                 public FieldExpression visit(Every every) {
                     return new Every(every.getExpression().accept(this), every.getPeriod());
                 }
 
+                @Override
                 public FieldExpression visit(On on) {
-                    return new On(mapDayOfWeek(sourceDef, targetDef, on.getTime()), on.getSpecialChar());
+                    return new On(mapDayOfWeek(sourceDef, targetDef, on.getTime()), on.getSpecialChar(),  on.getNth());
                 }
 
                 @Override

src/test/java/com/cronutils/Issue605Test.java

@@ -0,0 +1,43 @@
+package com.cronutils;
+
+import com.cronutils.mapper.CronMapper;
+import com.cronutils.model.Cron;
+import com.cronutils.model.CronType;
+import com.cronutils.model.definition.CronDefinition;
+import com.cronutils.model.definition.CronDefinitionBuilder;
+import com.cronutils.parser.CronParser;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import java.util.stream.Stream;
+
+import static com.cronutils.model.CronType.QUARTZ;
+import static com.cronutils.model.CronType.SPRING;
+import static org.junit.jupiter.api.Assertions.assertDoesNotThrow;
+
+class Issue605Test {
+
+    static Stream<Arguments> cronExpressions() {
+        return Stream.of(
+                Arguments.of(QUARTZ, CronMapper.fromQuartzToCron4j()),
+                Arguments.of(QUARTZ, CronMapper.fromQuartzToSpring()),
+                Arguments.of(QUARTZ, CronMapper.fromQuartzToUnix()),
+                Arguments.of(SPRING, CronMapper.fromSpringToQuartz())
+        );
+    }
+
+    @ParameterizedTest
+    @MethodSource("cronExpressions")
+    void testDayOfWeekMappingSpring(CronType cronType, CronMapper mapper) {
+        Cron cron = getCron(cronType, "0 0 0 ? * 5#1");
+        assertDoesNotThrow(() -> mapper.map(cron));
+    }
+
+    private Cron getCron(CronType cronType, @SuppressWarnings("SameParameterValue") final String quartzExpression) {
+        final CronDefinition cronDefinition = CronDefinitionBuilder.instanceDefinitionFor(cronType);
+        final CronParser parser = new CronParser(cronDefinition);
+        return parser.parse(quartzExpression);
+    }
+
+}

src/test/java/com/cronutils/utils/descriptor/TestDescriptor.java

@@ -5,6 +5,7 @@
 import java.util.Locale;
 import java.util.ResourceBundle;
 
+import com.cronutils.mapper.CronMapper;
 import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
@@ -351,11 +352,12 @@ public void testAtTimeOnThirdLastDayOfMonth() {
 		assertEquals("at 16:00:00pm, 3 days before the end of the month, every month", descriptor.describe(cron));
 	}
 
-	@Disabled
 	@Test
 	public void testAtTimeOnNthSpecificWeekdayOfMonth() {
 		final Cron cron = getCron("0 0 16 ? * 5#2 *");
-		assertEquals("at 16:00:00pm, on the 2nd Thursday of the month, every month", descriptor.describe(cron));
+		CronMapper quartzToUnixMapper = CronMapper.fromQuartzToUnix();
+		Cron mapped = quartzToUnixMapper.map(cron);
+		assertEquals("at 16:00 Thursday 2 of every month", descriptor.describe(mapped));
 	}
 
 	@Disabled