Ensure that single-parameter DTOs work with JPQL queries.

Closes #1869.

Author: gregturn

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

@@ -114,8 +114,8 @@ 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_OR_SUBSELECT = Pattern.compile("\\([\\s\\S]*order\\s+by\\s[\\s\\S]*\\)",
-			CASE_INSENSITIVE);
+	private static final Pattern ORDER_BY_IN_WINDOW_OR_SUBSELECT = Pattern
+			.compile("\\([\\s\\S]*order\\s+by\\s[\\s\\S]*\\)", CASE_INSENSITIVE);
 
 	private static final Pattern NAMED_PARAMETER = Pattern.compile(COLON_NO_DOUBLE_COLON + IDENTIFIER + "|#" + IDENTIFIER,
 			CASE_INSENSITIVE);
@@ -591,8 +591,9 @@ public static String createCountQueryFor(String originalQuery, @Nullable String
 
 			String variable = matcher.matches() ? matcher.group(VARIABLE_NAME_GROUP_INDEX) : null;
 			boolean useVariable = StringUtils.hasText(variable) //
-					&& !variable.startsWith(" new") //
-					&& !variable.startsWith("count(") //
+					&& !variable.startsWith("new") // select [new com.example.User...
+					&& !variable.startsWith(" new") // select distinct[ new com.example.User...
+					&& !variable.startsWith("count(") // select [count(...
 					&& !variable.contains(",");
 
 			String complexCountValue = matcher.matches() && StringUtils.hasText(matcher.group(COMPLEX_COUNT_FIRST_INDEX))

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

@@ -736,6 +736,29 @@ void countQueryUsesCorrectVariable() {
 				.isEqualTo("select count(us) FROM users_statuses us WHERE (user_created_at BETWEEN :fromDate AND :toDate)");
 	}
 
+	@Test // GH-1869
+	void createsCountQueryForJoinsWithTwoArgs() {
+
+		assertCountQuery("select distinct new User(u.name, u.age) from User u left outer join u.roles r WHERE r = ?",
+				"select count(distinct u) from User u left outer join u.roles r WHERE r = ?");
+	}
+
+	@Test // GH-1869
+	void createsCountQueryForDtoWithOneArg() {
+
+		assertCountQuery(
+				"SELECT new org.springframework.data.jpa.repository.sample.FirstNameDto(u.firstname) from User u where u.firstname = ?",
+				"select count(u) from User u where u.firstname = ?");
+	}
+
+	@Test // GH-1869
+	void createsCountQueryForDtoWithTwoArgs() {
+
+		assertCountQuery(
+				"SELECT new org.springframework.data.jpa.repository.sample.NameOnlyDto(u.firstname, u.lastname) from User u where u.firstname = ?",
+				"select count(u) from User u where u.firstname = ?");
+	}
+
 	@Test // GH-2496, GH-2522, GH-2537, GH-2045
 	void orderByShouldWorkWithSubSelectStatements() {