Fix missing DISTINCT in count queries.

The `COUNT_MATCH` does not consider line breaks after the `from` clause or the `where` clause. This leads to a no match scenario in the construction of the count query. With the fix we now consider line breaks/whitespaces after the `from` and `where` clause.

See #2341
Related tickets: #2177

Author: DiegoKrupitza

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

@@ -147,7 +147,7 @@ public abstract class QueryUtils {
 		builder.append(IDENTIFIER_GROUP);
 		builder.append("(.*)");
 
-		COUNT_MATCH = compile(builder.toString(), CASE_INSENSITIVE);
+		COUNT_MATCH = compile(builder.toString(), CASE_INSENSITIVE | DOTALL);
 
 		Map<PersistentAttributeType, Class<? extends Annotation>> persistentAttributeTypes = new HashMap<>();
 		persistentAttributeTypes.put(ONE_TO_ONE, OneToOne.class);
@@ -490,7 +490,8 @@ public static String createCountQueryFor(String originalQuery, @Nullable String
 			boolean useVariable = StringUtils.hasText(variable) //
 					&& !variable.startsWith(" new") //
 					&& !variable.startsWith("count(") //
-					&& !variable.contains(","); //
+					&& !variable.contains(",") //
+					&& !variable.contains("*");
 
 			String complexCountValue = matcher.matches() && StringUtils.hasText(matcher.group(COMPLEX_COUNT_FIRST_INDEX))
 					? COMPLEX_COUNT_VALUE

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

@@ -423,6 +423,11 @@ void createCountQuerySupportsWhitespaceCharacters() {
 						"  where user.age = 18\n ");
 	}
 
+	@Test // GH-2341
+	void createCountQueryStarCharacterConverted() {
+		assertThat(createCountQueryFor("select * from User user")).isEqualTo("select count(user) from User user");
+	}
+
 	@Test
 	void createCountQuerySupportsLineBreaksInSelectClause() {
 
@@ -524,6 +529,28 @@ void findProjectionClauseWithIncludedFrom() {
 		assertThat(QueryUtils.getProjection("select x, frommage, y from t")).isEqualTo("x, frommage, y");
 	}
 
+	@Test // GH-2341
+	void countProjectionDistrinctQueryIncludesNewLineAfterFromAndBeforeJoin() {
+		String originalQuery = "SELECT DISTINCT entity1\nFROM Entity1 entity1\nLEFT JOIN Entity2 entity2 ON entity1.key = entity2.key";
+
+		assertCountQuery(originalQuery,
+				"select count(DISTINCT entity1) FROM Entity1 entity1\nLEFT JOIN Entity2 entity2 ON entity1.key = entity2.key");
+	}
+
+	@Test // GH-2341
+	void countProjectionDistinctQueryIncludesNewLineAfterEntity() {
+		String originalQuery = "SELECT DISTINCT entity1\nFROM Entity1 entity1 LEFT JOIN Entity2 entity2 ON entity1.key = entity2.key";
+		assertCountQuery(originalQuery,
+				"select count(DISTINCT entity1) FROM Entity1 entity1 LEFT JOIN Entity2 entity2 ON entity1.key = entity2.key");
+	}
+
+	@Test // GH-2341
+	void countProjectionDistinctQueryIncludesNewLineAfterEntityAndBeforeWhere() {
+		String originalQuery = "SELECT DISTINCT entity1\nFROM Entity1 entity1 LEFT JOIN Entity2 entity2 ON entity1.key = entity2.key\nwhere entity1.id = 1799";
+		assertCountQuery(originalQuery,
+				"select count(DISTINCT entity1) FROM Entity1 entity1 LEFT JOIN Entity2 entity2 ON entity1.key = entity2.key\nwhere entity1.id = 1799");
+	}
+
 	private static void assertCountQuery(String originalQuery, String countQuery) {
 		assertThat(createCountQueryFor(originalQuery)).isEqualTo(countQuery);
 	}