DATAREDIS-843 - Adapt compare-and-set to changed transaction rollback response.

We now consider a transactional rollback that returns an empty EXEC result as rollback for the CAS (compare-and-set) operation. Previously, we checked only that the response of EXEC is not null. A rollback returns an empty list which was previously considered a successful CAS operation.

The code for CAS is now extracted to CompareAndSet and is reused from RedisAtomic implementations.

Original Pull Request: #349

src/test/java/org/springframework/data/redis/support/atomic/CompareAndSetIntegrationTests.java

@@ -0,0 +1,136 @@
+/*
+ * Copyright 2018 the original author or authors.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package org.springframework.data.redis.support.atomic;
+
+import static org.assertj.core.api.Assertions.*;
+
+import java.util.Collection;
+
+import org.junit.After;
+import org.junit.AfterClass;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.junit.runners.Parameterized;
+import org.junit.runners.Parameterized.Parameters;
+import org.springframework.data.redis.ConnectionFactoryTracker;
+import org.springframework.data.redis.connection.RedisConnection;
+import org.springframework.data.redis.connection.RedisConnectionFactory;
+import org.springframework.data.redis.core.RedisTemplate;
+import org.springframework.data.redis.core.ValueOperations;
+import org.springframework.data.redis.serializer.GenericToStringSerializer;
+import org.springframework.data.redis.serializer.StringRedisSerializer;
+
+/**
+ * Integration tests for {@link CompareAndSet}.
+ *
+ * @author Mark Paluch
+ */
+@RunWith(Parameterized.class)
+public class CompareAndSetIntegrationTests {
+
+	private static final String KEY = "key";
+
+	private final RedisConnectionFactory factory;
+	private final RedisTemplate<String, Long> template;
+	private final ValueOperations<String, Long> valueOps;
+
+	public CompareAndSetIntegrationTests(RedisConnectionFactory factory) {
+
+		this.factory = factory;
+
+		this.template = new RedisTemplate<>();
+		this.template.setConnectionFactory(factory);
+		this.template.setKeySerializer(StringRedisSerializer.UTF_8);
+		this.template.setValueSerializer(new GenericToStringSerializer<>(Long.class));
+		this.template.afterPropertiesSet();
+
+		this.valueOps = this.template.opsForValue();
+
+		ConnectionFactoryTracker.add(factory);
+	}
+
+	@After
+	public void stop() {
+		RedisConnection connection = factory.getConnection();
+		connection.flushDb();
+		connection.close();
+	}
+
+	@AfterClass
+	public static void cleanUp() {
+		ConnectionFactoryTracker.cleanUp();
+	}
+
+	@Parameters
+	public static Collection<Object[]> testParams() {
+		return AtomicCountersParam.testParams();
+	}
+
+	@Test // DATAREDIS-843
+	public void shouldUpdateCounter() {
+
+		long expected = 5;
+		long actual = 5;
+		long update = 6;
+
+		CompareAndSet<Long> cas = new CompareAndSet<>(() -> actual, newValue -> valueOps.set(KEY, newValue), KEY, expected,
+				update);
+
+		Boolean executed = this.template.execute(cas);
+
+		assertThat(executed).isTrue();
+		assertThat(valueOps.get(KEY)).isEqualTo(update);
+	}
+
+	@Test // DATAREDIS-843
+	public void expectationNotMet() {
+
+		long expected = 5;
+		long actual = 7;
+		long update = 6;
+
+		CompareAndSet<Long> cas = new CompareAndSet<>(() -> actual, newValue -> valueOps.set(KEY, newValue), KEY, expected,
+				update);
+
+		Boolean executed = this.template.execute(cas);
+
+		assertThat(executed).isFalse();
+		assertThat(valueOps.get(KEY)).isNull();
+	}
+
+	@Test // DATAREDIS-843
+	public void concurrentUpdate() {
+
+		long expected = 5;
+		long actual = 5;
+		long update = 6;
+		long concurrentlyUpdated = 7;
+
+		CompareAndSet<Long> cas = new CompareAndSet<>(() -> actual, newValue -> {
+
+			RedisConnection connection = this.factory.getConnection();
+			connection.set(KEY.getBytes(), Long.toString(concurrentlyUpdated).getBytes());
+			connection.close();
+
+			valueOps.set(KEY, newValue);
+		}, KEY, expected, update);
+
+		Boolean executed = this.template.execute(cas);
+
+		assertThat(executed).isFalse();
+		assertThat(valueOps.get(KEY)).isEqualTo(concurrentlyUpdated);
+	}
+}

src/test/java/org/springframework/data/redis/support/atomic/RedisAtomicDoubleTests.java

@@ -69,12 +69,6 @@ public class RedisAtomicDoubleTests extends AbstractRedisAtomicsTests {
 		ConnectionFactoryTracker.add(factory);
 	}
 
-	@Before
-	public void setUp() {
-		// Most atomic Double ops involve incrByFloat, which is new as of 2.6
-		assumeTrue(RedisTestProfileValueSource.matches("redisVersion", "2.6"));
-	}
-
 	@After
 	public void stop() {
 		RedisConnection connection = factory.getConnection();