jvz commented on code in PR #804:
URL: https://github.com/apache/logging-log4j2/pull/804#discussion_r846847224
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log4j-api-java9/src/test/java/org/apache/logging/log4j/util/java9/ServiceLoaderUtilTest.java:
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@@ -0,0 +1,77 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.logging.log4j.util.java9;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import java.lang.invoke.MethodHandles;
+import java.util.Collections;
+import java.util.List;
+import java.util.ServiceConfigurationError;
+import java.util.stream.Collectors;
+
+import org.apache.logging.log4j.util.PropertySource;
+import org.apache.logging.log4j.util.ServiceLoaderUtil;
+import org.apache.logging.log4j.util.java9.test.BetterService;
+import org.apache.logging.log4j.util.java9.test.Service;
+import org.junit.jupiter.api.Test;
+
+public class ServiceLoaderUtilTest {
+
+@Test
+public void testServiceResolution() {
+// Run only if we are a module
+if (ServiceLoaderUtil.class.getModule().isNamed()) {
Review Comment:
You can use `assumeTrue()` from JUnit here.
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log4j-api-java9/src/test/java/org/apache/logging/log4j/util/java9/ServiceLoaderUtilTest.java:
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@@ -0,0 +1,77 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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.apache.logging.log4j.util.java9;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
+import java.lang.invoke.MethodHandles;
+import java.util.Collections;
+import java.util.List;
+import java.util.ServiceConfigurationError;
+import java.util.stream.Collectors;
+
+import org.apache.logging.log4j.util.PropertySource;
+import org.apache.logging.log4j.util.ServiceLoaderUtil;
+import org.apache.logging.log4j.util.java9.test.BetterService;
+import org.apache.logging.log4j.util.java9.test.Service;
+import org.junit.jupiter.api.Test;
+
+public class ServiceLoaderUtilTest {
+
+@Test
+public void testServiceResolution() {
+// Run only if we are a module
+if (ServiceLoaderUtil.class.getModule().isNamed()) {
+List services = Collections.emptyList();
+// Service from test module
+try {
+services = ServiceLoaderUtil.loadServices(Service.class,
MethodHandles.lookup())
+.collect(Collectors.toList());
+} catch (ServiceConfigurationError e) {
Review Comment:
Nit: these types of tests can use `assertDoesNotThrow(() -> ...)`
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log4j-api-java9/src/test/java/org/apache/logging/log4j/util/java9/ServiceLoaderUtilTest.java:
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@@ -0,0 +1,77 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one or more
+ * contributor license agreements. See the NOTICE file distributed with
+ * this work for additional information regarding copyright ownership.
+ * The ASF licenses this file to You 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 languag
