Verify that projections work with subqueries.

Interface-based projections used to NOT work when the query had a subquery in it. But with the new query parser, it already handles it. So this simply captures the test providing that corner case. See #2008 Original Pull Request: #420

Author: gregturn

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/UserRepositoryFinderTests.java

@@ -315,4 +315,15 @@ void rejectsStreamExecutionIfNoSurroundingTransactionActive() {
 void executesNamedQueryWithConstructorExpression() {
 userRepository.findByNamedQueryWithConstructorExpression();
 }
+
+@Test // DATAJPA-1713, GH-2008
+public void selectProjectionWithSubselect() {
+
+List<UserRepository.NameOnly> dtos = userRepository.findProjectionBySubselect();
+
+assertThat(dtos).flatExtracting(UserRepository.NameOnly::getFirstname) //
+.containsExactly("Dave", "Carter", "Oliver August");
+assertThat(dtos).flatExtracting(UserRepository.NameOnly::getLastname) //
+.containsExactly("Matthews", "Beauford", "Matthews");
+}
 }

spring-data-jpa/src/test/java/org/springframework/data/jpa/repository/sample/UserRepository.java

@@ -718,6 +718,10 @@ List<String> findAllAndSortByFunctionResultNamedParameter(@Param("namedParameter
 nativeQuery = true)
 int mergeNativeStatement();
 
+// DATAJPA-1713, GH-2008
+@Query("select u from User u where u.firstname >= (select Min(u0.firstname) from User u0)")
+List<NameOnly> findProjectionBySubselect();
+
 interface RolesAndFirstname {
 
 String getFirstname();