Change "order by" pattern to match subqueries.

Fix alias detection bug occurring when using subqueries.
Closes spring-projects#2260

Author: TAndronicus

src/main/java/org/springframework/data/jpa/repository/query/QueryUtils.java

@@ -108,7 +108,7 @@ public abstract class QueryUtils {
 
 	private static final String EQUALS_CONDITION_STRING = "%s.%s = :%s";
 	private static final Pattern ORDER_BY = Pattern.compile("(order\\s+by\\s+)", CASE_INSENSITIVE);
-	private static final Pattern ORDER_BY_IN_WINDOW_CLAUSE = Pattern.compile("(over\\s*\\(\\s*[a-z ,]*order\\s+by\\s+[a-z ,]*\\s*\\))", CASE_INSENSITIVE);
+	private static final Pattern ORDER_BY_IN_WINDOW_OR_SUBSELECT = Pattern.compile("(\\(\\s*[a-z0-9 ,.*]*order\\s+by\\s+[a-z0-9 ,.]*\\s*\\))", CASE_INSENSITIVE);
 
 	private static final Pattern NAMED_PARAMETER = Pattern.compile(COLON_NO_DOUBLE_COLON + IDENTIFIER + "|#" + IDENTIFIER,
 			CASE_INSENSITIVE);
@@ -284,7 +284,7 @@ public static String applySorting(String query, Sort sort, @Nullable String alia
 	 * @return {@code true} if the query has {@code order by} clause, {@code false} otherwise
 	 */
 	private static boolean hasOrderByClause(String query) {
-		return countOccurences(ORDER_BY, query) > countOccurences(ORDER_BY_IN_WINDOW_CLAUSE, query);
+		return countOccurences(ORDER_BY, query) > countOccurences(ORDER_BY_IN_WINDOW_OR_SUBSELECT, query);
 	}
 
 	/**
@@ -416,10 +416,12 @@ private static String toJpaDirection(Order order) {
 	@Nullable
 	@Deprecated
 	public static String detectAlias(String query) {
-
+		String alias = null;
 		Matcher matcher = ALIAS_MATCH.matcher(query);
-
-		return matcher.find() ? matcher.group(2) : null;
+		while (matcher.find()) {
+			alias = matcher.group(2);
+		}
+		return alias;
 	}
 
 	/**

src/test/java/org/springframework/data/jpa/repository/query/QueryUtilsUnitTests.java

@@ -520,26 +520,48 @@ private static void assertCountQuery(String originalQuery, String countQuery) {
 	void applySortingAccountsForNativeWindowFunction() {
 		Sort sort = Sort.by(Order.desc("age"));
 
+		// order by absent
 		assertThat(QueryUtils.applySorting("select * from user u", sort))
 				.isEqualTo("select * from user u order by u.age desc");
+		// order by present
 		assertThat(QueryUtils.applySorting("select * from user u order by u.lastname", sort))
 				.isEqualTo("select * from user u order by u.lastname, u.age desc");
+		// partition by
 		assertThat(QueryUtils.applySorting("select dense_rank() over (partition by age) from user u", sort))
 				.isEqualTo("select dense_rank() over (partition by age) from user u order by u.age desc");
+		// order by in over clause
 		assertThat(QueryUtils.applySorting("select dense_rank() over (order by lastname) from user u", sort))
 				.isEqualTo("select dense_rank() over (order by lastname) from user u order by u.age desc");
+		// order by in over clause (additional spaces)
 		assertThat(QueryUtils.applySorting("select dense_rank() over ( order by lastname ) from user u", sort))
 				.isEqualTo("select dense_rank() over ( order by lastname ) from user u order by u.age desc");
+		// order by in over clause + at the end
 		assertThat(QueryUtils.applySorting("select dense_rank() over (order by lastname) from user u order by u.lastname", sort))
 				.isEqualTo("select dense_rank() over (order by lastname) from user u order by u.lastname, u.age desc");
+		// partition by + order by in over clause
 		assertThat(QueryUtils.applySorting("select dense_rank() over (partition by active, age order by lastname) from user u", sort))
 				.isEqualTo("select dense_rank() over (partition by active, age order by lastname) from user u order by u.age desc");
+		// partition by + order by in over clause + order by at the end
 		assertThat(QueryUtils.applySorting("select dense_rank() over (partition by active, age order by lastname) from user u order by active", sort))
 				.isEqualTo("select dense_rank() over (partition by active, age order by lastname) from user u order by active, u.age desc");
+		// partition by + order by in over clause + frame clause
 		assertThat(QueryUtils.applySorting("select dense_rank() over ( partition by active, age order by username rows between current row and unbounded following ) from user u", sort))
 				.isEqualTo("select dense_rank() over ( partition by active, age order by username rows between current row and unbounded following ) from user u order by u.age desc");
+		// partition by + order by in over clause + frame clause + order by at the end
 		assertThat(QueryUtils.applySorting("select dense_rank() over ( partition by active, age order by username rows between current row and unbounded following ) from user u order by active", sort))
 				.isEqualTo("select dense_rank() over ( partition by active, age order by username rows between current row and unbounded following ) from user u order by active, u.age desc");
+		// order by in subselect (select expression)
+		assertThat(QueryUtils.applySorting("select lastname, (select i.id from item i order by i.id limit 1) from user u", sort))
+				.isEqualTo("select lastname, (select i.id from item i order by i.id limit 1) from user u order by u.age desc");
+		// order by in subselect (select expression) + at the end
+		assertThat(QueryUtils.applySorting("select lastname, (select i.id from item i order by 1 limit 1) from user u order by active", sort))
+				.isEqualTo("select lastname, (select i.id from item i order by 1 limit 1) from user u order by active, u.age desc");
+		// order by in subselect (from expression)
+		assertThat(QueryUtils.applySorting("select * from (select * from user order by age desc limit 10) u", sort))
+				.isEqualTo("select * from (select * from user order by age desc limit 10) u order by age desc");
+		// order by in subselect (from expression) + at the end
+		assertThat(QueryUtils.applySorting("select * from (select * from user order by 1, 2, 3 desc limit 10) u order by u.active asc", sort))
+				.isEqualTo("select * from (select * from user order by 1, 2, 3 desc limit 10) u order by u.active asc, age desc");
 	}
 
 }