DATAJPA-960 - Fixed alias detection for queries not containing an alias.

We're now more lenient against manually defined queries that do not contain aliases when adding order by clauses to them. The alias detection now doesn't accidentally pick up "where" anymore in case no primary alias is declared and the code applying the order by clause only qualifies the expressions created if there actually is an alias in the first place.

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

@@ -110,7 +110,7 @@ public abstract class QueryUtils {
 		builder.append(IDENTIFIER_GROUP); // Entity name, can be qualified (any
 		builder.append("(?:\\sas)*"); // exclude possible "as" keyword
 		builder.append("(?:\\s)+"); // at least one space separating
-		builder.append("(\\w*)"); // the actual alias
+		builder.append("(?!(?:where))(\\w*)"); // the actual alias
 
 		ALIAS_MATCH = compile(builder.toString(), CASE_INSENSITIVE);
 
@@ -199,8 +199,7 @@ public abstract class QueryUtils {
 	 * @return
 	 */
 	public static String applySorting(String query, Sort sort) {
-
-		return applySorting(query, sort, DEFAULT_ALIAS);
+		return applySorting(query, sort, detectAlias(query));
 	}
 
 	/**
@@ -259,7 +258,8 @@ public abstract class QueryUtils {
 			}
 		}
 
-		String reference = qualifyReference ? String.format("%s.%s", alias, property) : property;
+		String reference = qualifyReference && StringUtils.hasText(alias) ? String.format("%s.%s", alias, property)
+				: property;
 		String wrapped = order.isIgnoreCase() ? String.format("lower(%s)", reference) : reference;
 
 		return String.format("%s %s", wrapped, toJpaDirection(order));

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

@@ -352,6 +352,15 @@ public class QueryUtilsUnitTests {
 		assertThat(hasConstructorExpression("select new foo.bar.FooBar(\na.id) from DtoA a "), is(true));
 	}
 
+	/**
+	 * @see DATAJPA-960
+	 */
+	@Test
+	public void doesNotQualifySortIfNoAliasDetected() {
+		assertThat(applySorting("from mytable where ?1 is null", new Sort("firstname")),
+				endsWith("order by firstname asc"));
+	}
+
 	private static void assertCountQuery(String originalQuery, String countQuery) {
 		assertThat(createCountQueryFor(originalQuery), is(countQuery));
 	}