Prevent pausing of the logging system

When the test context framework pauses a cached context, the logging
lifecycle's stop() cleans up the logging system. With Logback this
uninstalls the JUL bridge handler for the whole JVM and nothing
reinstalls it when the context is restarted, so JUL output is lost
in later tests that reuse the context.

This commit makes the lifecycle non-pauseable so that cleanup only
happens on close, as it already does for the web server lifecycles.

See gh-51959

Signed-off-by: Raphael Vullriede <raphael@osslabz.net>

core/spring-boot-test/build.gradle

@@ -61,6 +61,7 @@ dependencies {
 	testRuntimeOnly("org.aspectj:aspectjrt")
 	testRuntimeOnly("org.aspectj:aspectjweaver")
 	testRuntimeOnly("org.junit.vintage:junit-vintage-engine")
+	testRuntimeOnly("org.slf4j:jul-to-slf4j")
 }
 
 tasks.named("compileTestJava") {

core/spring-boot-test/src/test/java/org/springframework/boot/test/context/LoggingApplicationListenerTcfCacheContextPausingTests.java

@@ -0,0 +1,93 @@
+/*
+ * Copyright 2012-present 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
+ *
+ *      https://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.boot.test.context;
+
+import java.util.logging.Logger;
+
+import org.junit.jupiter.api.ClassOrderer;
+import org.junit.jupiter.api.Nested;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.TestClassOrder;
+import org.junit.jupiter.api.extension.ExtendWith;
+
+import org.springframework.boot.SpringBootConfiguration;
+import org.springframework.boot.context.logging.LoggingApplicationListener;
+import org.springframework.boot.test.system.CapturedOutput;
+import org.springframework.boot.test.system.OutputCaptureExtension;
+import org.springframework.context.annotation.Import;
+import org.springframework.test.context.TestPropertySource;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests for {@link LoggingApplicationListener} when the test context framework pauses a
+ * context while it's in the cache.
+ *
+ * @author Raphael Vullriede
+ */
+@SpringBootTest
+@ExtendWith(OutputCaptureExtension.class)
+@TestClassOrder(ClassOrderer.ClassName.class)
+class LoggingApplicationListenerTcfCacheContextPausingTests {
+
+	private static void assertJulOutputIsLogged(CapturedOutput output) {
+		Logger.getLogger("test").severe("Hello from JUL");
+		assertThat(output).contains("Hello from JUL");
+	}
+
+	@Nested
+	@Import(TestConfig.class)
+	@TestPropertySource(properties = "context=one")
+	class ContextOne {
+
+		@Test
+		void test(CapturedOutput output) {
+			assertJulOutputIsLogged(output);
+		}
+
+	}
+
+	@Nested
+	@Import(TestConfig.class)
+	@TestPropertySource(properties = "context=two")
+	class ContextTwo {
+
+		@Test
+		void test(CapturedOutput output) {
+			assertJulOutputIsLogged(output);
+		}
+
+	}
+
+	@Nested
+	@Import(TestConfig.class)
+	@TestPropertySource(properties = "context=one")
+	class ReuseContextOne {
+
+		@Test
+		void test(CapturedOutput output) {
+			assertJulOutputIsLogged(output);
+		}
+
+	}
+
+	@SpringBootConfiguration(proxyBeanMethods = false)
+	static class TestConfig {
+
+	}
+
+}

core/spring-boot/src/main/java/org/springframework/boot/context/logging/LoggingApplicationListener.java

@@ -488,6 +488,11 @@ public class LoggingApplicationListener implements GenericApplicationListener {
 			return Integer.MIN_VALUE + 1;
 		}
 
+		@Override
+		public boolean isPauseable() {
+			return false;
+		}
+
 	}
 
 }