#363 - Polishing.

Added an integration test and tweaked the conversions to make it succeed.
The converter now does not rely on the driver to do the conversion anymore.

Original pull request: #360.

src/main/java/org/springframework/data/r2dbc/convert/R2dbcConverters.java

@@ -186,7 +186,7 @@ abstract class R2dbcConverters {
 			@Override
 			public T convert(Row source) {
 
-				Object object = source.get(0, targetType);
+				Object object = source.get(0);
 
 				return (object != null ? NumberUtils.convertNumberToTargetClass((Number) object, this.targetType) : null);
 			}

src/test/java/org/springframework/data/r2dbc/repository/AbstractR2dbcRepositoryIntegrationTests.java

@@ -285,6 +285,18 @@ public abstract class AbstractR2dbcRepositoryIntegrationTests extends R2dbcInteg
 		assertThat(count).hasEntrySatisfying("count", numberOf(2));
 	}
 
+	@Test // gh-363
+	public void derivedQueryWithCountProjection() {
+
+		shouldInsertNewItems();
+
+		repository.countByNameContains("SCH") //
+				.as(StepVerifier::create) //
+				.assertNext(i -> assertThat(i).isEqualTo(2))
+				.verifyComplete();
+
+	}
+
 	private Condition<? super Object> numberOf(int expected) {
 		return new Condition<>(it -> {
 			return it instanceof Number && ((Number) it).intValue() == expected;
@@ -312,6 +324,8 @@ public abstract class AbstractR2dbcRepositoryIntegrationTests extends R2dbcInteg
 
 		@Query("DELETE from legoset where manual = :manual")
 		Mono<Void> deleteAllByManual(int manual);
+
+		Mono<Integer> countByNameContains(String namePart);
 	}
 
 	@Getter

src/test/java/org/springframework/data/r2dbc/repository/query/PartTreeR2dbcQueryUnitTests.java

@@ -619,7 +619,7 @@ public class PartTreeR2dbcQueryUnitTests {
 				+ ".foo FROM " + TABLE + " WHERE " + TABLE + ".first_name = $1");
 	}
 
-	@Test // DATAJDBC-534
+	@Test // gh-363
 	public void createsQueryForCountProjection() throws Exception {
 
 		R2dbcQueryMethod queryMethod = getQueryMethod("countByFirstName", String.class);