Converting tests to junit5 (#4699)

* started converting tests to junit5

* replaced TempFolder with JUnit TempDir

* migrated some test classes to JUnit5

* migrated a parameterized testclass to junit5

* Update core/pom.xml

Co-authored-by: Mark Waite <mark.earl.waite@gmail.com>

* replaced junit4 with junit5-vintage engine

Co-authored-by: Mark Waite <mark.earl.waite@gmail.com>

core/pom.xml

@@ -40,6 +40,7 @@ THE SOFTWARE.
   <properties>
     <staplerFork>true</staplerFork>
     <hamcrest.version>2.2</hamcrest.version>
+    <junit.jupiter.version>5.6.2</junit.jupiter.version>
   </properties>
 
   <dependencyManagement>
@@ -428,8 +429,27 @@ THE SOFTWARE.
       <artifactId>spring-aop</artifactId>
     </dependency>
     <dependency>
-      <groupId>junit</groupId>
+      <groupId>org.junit.jupiter</groupId>
-      <artifactId>junit</artifactId>
+      <artifactId>junit-jupiter-api</artifactId>
+      <version>${junit.jupiter.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter-engine</artifactId>
+      <version>${junit.jupiter.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.vintage</groupId>
+      <artifactId>junit-vintage-engine</artifactId>
+      <version>${junit.jupiter.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>org.junit.jupiter</groupId>
+      <artifactId>junit-jupiter</artifactId>
+      <version>${junit.jupiter.version}</version>
       <scope>test</scope>
     </dependency>
     <dependency>

core/src/test/java/hudson/ClassicPluginStrategyTest.java

@@ -25,12 +25,14 @@ package hudson;
 
 import hudson.util.VersionNumber;
 import jenkins.plugins.DetachedPluginsUtil;
-import org.junit.Assert;
+import org.junit.jupiter.api.Test;
-import org.junit.Test;
 
 import java.util.List;
 
 import static jenkins.plugins.DetachedPluginsUtil.DetachedPlugin;
+import static org.junit.jupiter.api.Assertions.assertNotNull;
+import static org.junit.jupiter.api.Assertions.assertNull;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 /**
  * @author <a href="mailto:tom.fennelly@gmail.com">tom.fennelly@gmail.com</a>
@@ -41,21 +43,21 @@ public class ClassicPluginStrategyTest {
     public void test_getDetachedPlugins() {
         List<DetachedPlugin> list = DetachedPluginsUtil.getDetachedPlugins(new VersionNumber("1.296"));
 
-        Assert.assertTrue(list.size() >= 14); // There were 14 at the time of writing this test
+        assertTrue(list.size() >= 14); // There were 14 at the time of writing this test
-        Assert.assertNotNull(findPlugin("maven-plugin", list));
+        assertNotNull(findPlugin("maven-plugin", list));
-        Assert.assertNotNull(findPlugin("subversion", list));
+        assertNotNull(findPlugin("subversion", list));
 
         // Narrow the list to since "1.310" (the subversion detach version).
         list = DetachedPluginsUtil.getDetachedPlugins(new VersionNumber("1.310"));
         // Maven should no longer be in the list, but subversion should.
-        Assert.assertNull(findPlugin("maven-plugin", list));
+        assertNull(findPlugin("maven-plugin", list));
-        Assert.assertNotNull(findPlugin("subversion", list));
+        assertNotNull(findPlugin("subversion", list));
 
         // Narrow the list to since "1.311" (after the subversion detach version).
         list = DetachedPluginsUtil.getDetachedPlugins(new VersionNumber("1.311"));
         // Neither Maven or subversion should be in the list.
-        Assert.assertNull(findPlugin("maven-plugin", list));
+        assertNull(findPlugin("maven-plugin", list));
-        Assert.assertNull(findPlugin("subversion", list));
+        assertNull(findPlugin("subversion", list));
     }
 
     private DetachedPlugin findPlugin(String shortName, List<DetachedPlugin> list) {

core/src/test/java/hudson/EnvVarsTest.java

@@ -25,15 +25,20 @@ package hudson;
 
 import hudson.EnvVars.OverrideOrderCalculator;
 
-import java.util.*;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.HashSet;
+import java.util.List;
+import java.util.TreeMap;
 
 import com.google.common.collect.Sets;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+
 /**
  * @author Kohsuke Kawaguchi
  */
@@ -118,7 +123,7 @@ public class EnvVarsTest {
 
         OverrideOrderCalculator calc = new OverrideOrderCalculator(env, overrides);
         List<String> order = calc.getOrderedVariableNames();
-        assertEquals(Arrays.asList("PATH"), order);
+        assertEquals(Collections.singletonList("PATH"), order);
     }
 
     @Test

core/src/test/java/hudson/MarkupTextTest.java

@@ -23,14 +23,14 @@
  */
 package hudson;
 
-import static org.junit.Assert.assertEquals;
-
 import hudson.MarkupText.SubText;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 import java.util.List;
 import java.util.regex.Pattern;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 /**
  * @author Kohsuke Kawaguchi
  */
@@ -60,8 +60,8 @@ public class MarkupTextTest {
     public void findTokensOnSubText() {
         MarkupText t = new MarkupText("Fixed 2 issues in this commit, fixing issue 155, 145");
         List<SubText> tokens = t.findTokens(Pattern.compile("issue .*"));
-        assertEquals("Expected one token", 1, tokens.size());
+        assertEquals(1, tokens.size(), "Expected one token");
-        assertEquals("Expected single token was incorrect", "issue 155, 145", tokens.get(0).group(0));
+        assertEquals("issue 155, 145", tokens.get(0).group(0), "Expected single token was incorrect");
         for (SubText st : tokens.get(0).findTokens(Pattern.compile("([0-9]+)")))
             st.surroundWith("<$1>","<$1>");
 

core/src/test/java/hudson/PluginManagerTest.java

@@ -28,35 +28,40 @@ import java.io.File;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import org.apache.tools.ant.filters.StringInputStream;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
+import org.junit.jupiter.api.io.TempDir;
 import org.xml.sax.SAXException;
 import java.io.IOException;
 import java.net.MalformedURLException;
 import java.net.URL;
+import java.nio.file.Path;
 import java.util.jar.Attributes;
 import java.util.jar.Manifest;
 import java.util.zip.ZipEntry;
 import java.util.zip.ZipOutputStream;
 import org.apache.commons.io.FileUtils;
+import org.jvnet.hudson.test.Issue;
+
 import static org.hamcrest.CoreMatchers.*;
+import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.core.IsInstanceOf.instanceOf;
 import static org.hamcrest.core.StringContains.containsString;
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.fail;
-import static org.junit.Assert.fail;
+
-import org.junit.Rule;
-import org.junit.rules.TemporaryFolder;
-import org.jvnet.hudson.test.Issue;
- 
 /**
  * Tests of {@link PluginManager}.
  */
 public class PluginManagerTest {
 
-    @Rule public TemporaryFolder tmp = new TemporaryFolder();
+    @TempDir Path tmp;
 
-    @Test public void parseRequestedPlugins() throws Exception {
+    @Test
-        assertEquals("{other=2.0, stuff=1.2}", new LocalPluginManager(tmp.getRoot())
+    public void parseRequestedPlugins() throws Exception {
+        Path output = Files.createFile(
+                tmp.resolve("output.txt")
+        );
+        assertEquals("{other=2.0, stuff=1.2}", new LocalPluginManager(output.toFile())
                 .parseRequestedPlugins(new StringInputStream("<root><stuff plugin='stuff@1.0'><more plugin='other@2.0'><things plugin='stuff@1.2'/></more></stuff></root>")).toString());
     }
 
@@ -145,12 +150,11 @@ public class PluginManagerTest {
                 "Plugin-Developers: ";
     
     private File createHpiWithManifest() throws IOException {
-        File newFolder = tmp.newFolder("myJar");
         String manifestPath = "META-INF/MANIFEST.MF";
         new File("META-INF").mkdir();
-        FileUtils.write(new File(newFolder, manifestPath), SAMPLE_MANIFEST_FILE, StandardCharsets.UTF_8);
+        FileUtils.write(new File(tmp.toFile(), manifestPath), SAMPLE_MANIFEST_FILE, StandardCharsets.UTF_8);
         
-        final File f = new File(tmp.getRoot(), "my.hpi");
+        final File f = new File(tmp.toFile(), "my.hpi");
         try(ZipOutputStream out = new ZipOutputStream(Files.newOutputStream(f.toPath()))) {
             ZipEntry e = new ZipEntry(manifestPath);
             out.putNextEntry(e);

core/src/test/java/hudson/PluginWrapperTest.java

@@ -10,36 +10,37 @@ import java.util.jar.Attributes;
 import java.util.jar.Manifest;
 
 import jenkins.model.Jenkins;
-import org.junit.After;
+import org.junit.jupiter.api.AfterAll;
-import org.junit.Before;
+import org.junit.jupiter.api.BeforeAll;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.mockito.invocation.InvocationOnMock;
 import org.mockito.stubbing.Answer;
 
-import static org.hamcrest.CoreMatchers.containsString;
-import static org.junit.Assert.assertEquals;
-import static org.junit.Assert.assertFalse;
-import static org.hamcrest.MatcherAssert.assertThat;
-import static org.junit.Assert.assertTrue;
-import static org.junit.Assert.fail;
 import org.jvnet.hudson.test.Issue;
+
+import static org.hamcrest.CoreMatchers.containsString;
+import static org.hamcrest.MatcherAssert.assertThat;
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+import static org.junit.jupiter.api.Assertions.fail;
 import static org.mockito.ArgumentMatchers.any;
 import static org.mockito.Mockito.mock;
 import static org.mockito.Mockito.when;
 
 public class PluginWrapperTest {
 
-    private Locale loc;
+    private static Locale loc;
     
-    @Before
+    @BeforeAll
-    public void before() throws Exception {
+    public static void before() {
         Jenkins.VERSION = "2.0"; // Some value needed - tests will overwrite if necessary
         loc = Locale.getDefault();
         Locale.setDefault(new Locale("en", "GB"));
     }
 
-    @After
+    @AfterAll
-    public void after() {
+    public static void after() {
         Locale.setDefault(loc);
     }
     
@@ -62,7 +63,7 @@ public class PluginWrapperTest {
     }
 
     @Test
-    public void jenkinsCoreTooOld() throws Exception {
+    public void jenkinsCoreTooOld() {
         PluginWrapper pw = pluginWrapper("fake").requiredCoreVersion("3.0").buildLoaded();
         try {
             pw.resolvePluginDependencies();
@@ -73,7 +74,7 @@ public class PluginWrapperTest {
     }
 
     @Test
-    public void dependencyNotInstalled() throws Exception {
+    public void dependencyNotInstalled() {
         PluginWrapper pw = pluginWrapper("dependee").deps("dependency:42").buildLoaded();
         try {
             pw.resolvePluginDependencies();
@@ -84,7 +85,7 @@ public class PluginWrapperTest {
     }
 
     @Test
-    public void dependencyOutdated() throws Exception {
+    public void dependencyOutdated() {
         pluginWrapper("dependency").version("3").buildLoaded();
         PluginWrapper pw = pluginWrapper("dependee").deps("dependency:5").buildLoaded();
         try {
@@ -96,7 +97,7 @@ public class PluginWrapperTest {
     }
 
     @Test
-    public void dependencyFailedToLoad() throws Exception {
+    public void dependencyFailedToLoad() {
         pluginWrapper("dependency").version("5").buildFailed();
         PluginWrapper pw = pluginWrapper("dependee").deps("dependency:3").buildLoaded();
         try {

core/src/test/java/hudson/ProxyConfigurationTest.java

@@ -23,12 +23,12 @@
  */
 package hudson;
 
-import static org.junit.Assert.assertEquals;
+import org.junit.jupiter.api.Test;
-
-import org.junit.Test;
 
 import java.net.Proxy;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 public class ProxyConfigurationTest {
 
     @Test

core/src/test/java/hudson/console/UrlAnnotatorTest.java

@@ -23,13 +23,13 @@
  */
 package hudson.console;
 
-import static org.junit.Assert.assertEquals;
 import hudson.MarkupText;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
-
 import org.jvnet.hudson.test.Issue;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
 /**
  * @author Alan Harder
  */

core/src/test/java/hudson/slaves/ComputerLauncherTest.java

@@ -31,31 +31,32 @@ import java.io.PrintStream;
 import java.io.StringReader;
 
 import org.apache.commons.io.output.NullOutputStream;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hudson.test.Issue;
 
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertThrows;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 
 public class ComputerLauncherTest {
 
-    @Test(expected=IOException.class) public void jdk7() throws IOException {
+    @Test public void jdk7() {
-        assertChecked("java version \"1.7.0_05\"\nJava(TM) SE Runtime Environment (build 1.7.0_05-b05)\nJava HotSpot(TM) Server VM (build 23.1-b03, mixed mode)\n", "1.7.0");
+        assertThrows(IOException.class, () -> assertChecked("java version \"1.7.0_05\"\nJava(TM) SE Runtime Environment (build 1.7.0_05-b05)\nJava HotSpot(TM) Server VM (build 23.1-b03, mixed mode)\n", "1.7.0"));
     }
 
-    @Test(expected=IOException.class) public void openJDK7() throws IOException {
+    @Test public void openJDK7() {
-        assertChecked("openjdk version \"1.7.0-internal\"\nOpenJDK Runtime Environment (build 1.7.0-internal-pkgsrc_2010_01_03_06_54-b00)\nOpenJDK 64-Bit Server VM (build 17.0-b04, mixed mode)\n", "1.7.0");
+        assertThrows(IOException.class, () -> assertChecked("openjdk version \"1.7.0-internal\"\nOpenJDK Runtime Environment (build 1.7.0-internal-pkgsrc_2010_01_03_06_54-b00)\nOpenJDK 64-Bit Server VM (build 17.0-b04, mixed mode)\n", "1.7.0"));
     }
 
-    @Test(expected=IOException.class) public void jdk6() throws IOException {
+    @Test public void jdk6() {
-        assertChecked("java version \"1.6.0_33\"\nJava(TM) SE Runtime Environment (build 1.6.0_33-b03)\nJava HotSpot(TM) Server VM (build 20.8-b03, mixed mode)\n", "1.6.0");
+        assertThrows(IOException.class, () -> assertChecked("java version \"1.6.0_33\"\nJava(TM) SE Runtime Environment (build 1.6.0_33-b03)\nJava HotSpot(TM) Server VM (build 20.8-b03, mixed mode)\n", "1.6.0"));
     }
 
-    @Test(expected=IOException.class) public void jdk5() throws IOException {
+    @Test public void jdk5() {
-        ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.5.0_22\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_22-b03)\nJava HotSpot(TM) Server VM (build 1.5.0_22-b03, mixed mode)\n")));
+        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.5.0_22\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.5.0_22-b03)\nJava HotSpot(TM) Server VM (build 1.5.0_22-b03, mixed mode)\n"))));
     }
 
-    @Test(expected=IOException.class) public void j2sdk4() throws IOException {
+    @Test public void j2sdk4() {
-        ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.4.2_19\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_19-b04)\nJava HotSpot(TM) Client VM (build 1.4.2_19-b04, mixed mode)\n")));
+        assertThrows(IOException.class, () -> ComputerLauncher.checkJavaVersion(new PrintStream(new NullOutputStream()), "-", new BufferedReader(new StringReader("java version \"1.4.2_19\"\nJava(TM) 2 Runtime Environment, Standard Edition (build 1.4.2_19-b04)\nJava HotSpot(TM) Client VM (build 1.4.2_19-b04, mixed mode)\n"))));
     }
 
     @Test public void jdk8() throws IOException {
@@ -102,7 +103,6 @@ public class ComputerLauncherTest {
         ByteArrayOutputStream os = new ByteArrayOutputStream();
         ComputerLauncher.checkJavaVersion(new PrintStream(os), "bin/java", new BufferedReader(new StringReader(text)));
         String logged = os.toString();
-        assertTrue(logged, logged.contains(Messages.ComputerLauncher_JavaVersionResult("bin/java", spec)));
+        assertTrue(logged.contains(Messages.ComputerLauncher_JavaVersionResult("bin/java", spec)), logged);
     }
-
 }

core/src/test/java/hudson/slaves/NodeListTest.java

@@ -23,8 +23,8 @@
  */
 package hudson.slaves;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.jupiter.api.Assertions.assertEquals;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertTrue;
 import static org.mockito.Mockito.*;
 
 import jenkins.model.Jenkins;
@@ -35,7 +35,7 @@ import java.io.File;
 import java.nio.charset.Charset;
 
 import org.apache.commons.io.FileUtils;
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 
 /**
  * @author Kohsuke Kawaguchi

core/src/test/java/hudson/triggers/SCMTriggerTest.java

@@ -23,7 +23,7 @@
  */
 package hudson.triggers;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hudson.test.Issue;
 
 /**

core/src/test/java/jenkins/model/labels/LabelAutoCompleteSeederTest.java

@@ -24,63 +24,47 @@
 
 package jenkins.model.labels;
 
-import java.util.Arrays;
+import java.util.Collections;
-import java.util.Collection;
 import java.util.List;
-import org.junit.Test;
+import java.util.stream.Stream;
-import org.junit.runner.RunWith;
+
-import org.junit.runners.Parameterized;
+import org.junit.jupiter.params.ParameterizedTest;
+import org.junit.jupiter.params.provider.Arguments;
+import org.junit.jupiter.params.provider.MethodSource;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
 
-import static org.junit.Assert.assertEquals;
 
 /**
  *
  * @author dty
  */
-@RunWith(Parameterized.class)
 public class LabelAutoCompleteSeederTest {
 
-    public static class TestData {
+    static Stream<Arguments> localParameters()
-        private final String seed;
+    {
-        private final List<String> expected;
+        return Stream.of(
-        
+                Arguments.of("", Collections.singletonList("")),
-        public TestData(String seed, String... expected) {
+                Arguments.of("\"", Collections.singletonList("")),
-            this.seed = seed;
+                Arguments.of("\"\"", Collections.singletonList("")),
-            this.expected = Arrays.asList(expected);
+                Arguments.of("freebsd", Collections.singletonList("freebsd")),
-        }
+                Arguments.of(" freebsd", Collections.singletonList("freebsd")),
-    }
+                Arguments.of("freebsd ", Collections.singletonList("")),
-    
+                Arguments.of("freebsd 6", Collections.singletonList("6")),
-    @Parameterized.Parameters
+                Arguments.of("\"freebsd", Collections.singletonList("freebsd")),
-    public static Collection<Object[]> data() {
+                Arguments.of("\"freebsd ", Collections.singletonList("freebsd ")),
-        return Arrays.asList( new Object[][] {
+                Arguments.of("\"freebsd\"", Collections.singletonList("")),
-                    { new TestData("", "") },
+                Arguments.of("\"freebsd\" ", Collections.singletonList("")),
-                    { new TestData("\"", "") },
+                Arguments.of("\"freebsd 6", Collections.singletonList("freebsd 6")),
-                    { new TestData("\"\"", "") },
+                Arguments.of("\"freebsd 6\"", Collections.singletonList(""))
-                    { new TestData("freebsd", "freebsd") },
+        );
-                    { new TestData(" freebsd", "freebsd") },
-                    { new TestData("freebsd ", "") },
-                    { new TestData("freebsd 6", "6") },
-                    { new TestData("\"freebsd", "freebsd") },
-                    { new TestData("\"freebsd ", "freebsd ") },
-                    { new TestData("\"freebsd\"", "") },
-                    { new TestData("\"freebsd\" ", "") },
-                    { new TestData("\"freebsd 6", "freebsd 6") },
-                    { new TestData("\"freebsd 6\"", "") },
-               });
     }
 
-    private final String seed;
+    @ParameterizedTest( name = "{index}" )
-    private final List<String> expected;
+    @MethodSource( "localParameters" )
-
+    public void testAutoCompleteSeeds(String underTest, List<String> expected) {
-    public LabelAutoCompleteSeederTest(TestData dataSet) {
+        LabelAutoCompleteSeeder seeder = new LabelAutoCompleteSeeder(underTest);
-        this.seed = dataSet.seed;
-        this.expected = dataSet.expected;
-    }
-
-    @Test
-    public void testAutoCompleteSeeds() throws Exception {
-        LabelAutoCompleteSeeder seeder = new LabelAutoCompleteSeeder(seed);
         assertEquals(expected, seeder.getSeeds());
-    }
 
+    }
 }

core/src/test/java/jenkins/util/AtmostOneTaskExecutorTest.java

@@ -1,13 +1,16 @@
 package jenkins.util;
 
 import hudson.util.OneShotEvent;
+import org.junit.Test;
+
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
 import java.util.concurrent.atomic.AtomicInteger;
-import static org.junit.Assert.assertEquals;
+
-import static org.junit.Assert.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertEquals;
-import org.junit.Test;
+import static org.junit.jupiter.api.Assertions.assertFalse;
+
 
 public class AtmostOneTaskExecutorTest {
 

core/src/test/java/jenkins/util/TimerTest.java

@@ -1,11 +1,8 @@
 package jenkins.util;
 
-import static org.junit.Assert.fail;
-
 import groovy.lang.GroovyClassLoader;
 import hudson.triggers.SafeTimerTask;
-import org.junit.Assert;
+import org.junit.jupiter.api.Test;
-import org.junit.Test;
 import org.jvnet.hudson.test.Issue;
 
 import java.util.concurrent.CountDownLatch;
@@ -13,6 +10,9 @@ import java.util.concurrent.ScheduledExecutorService;
 import java.util.concurrent.ScheduledFuture;
 import java.util.concurrent.TimeUnit;
 
+import static org.junit.jupiter.api.Assertions.assertEquals;
+import static org.junit.jupiter.api.Assertions.fail;
+
 public class TimerTest {
 
     /**
@@ -35,7 +35,7 @@ public class TimerTest {
 
         SafeTimerTask task2 = new SafeTimerTask() {
             @Override
-            protected void doRun() throws Exception {
+            protected void doRun() {
                 stopLatch.countDown();
             }
         };
@@ -60,7 +60,7 @@ public class TimerTest {
         final CountDownLatch startLatch = new CountDownLatch(threadCount);
 
         final ClassLoader[] contextClassloaders = new ClassLoader[threadCount];
-        ScheduledFuture[] futures = new ScheduledFuture[threadCount];
+        ScheduledFuture<?>[] futures = new ScheduledFuture[threadCount];
         final ClassLoader bogusClassloader = new GroovyClassLoader();
 
         Runnable timerTest = new Runnable() {
@@ -88,12 +88,12 @@ public class TimerTest {
         };
 
         Thread t = new Thread(timerTest);
-        t.run();
+        t.start();
         t.join(1000L);
 
         for (int i=0; i<threadCount; i++) {
             futures[i].get();
-            Assert.assertEquals(Timer.class.getClassLoader(), contextClassloaders[i]);
+            assertEquals(Timer.class.getClassLoader(), contextClassloaders[i]);
         }
     }
 }

core/src/test/java/jenkins/util/UrlHelperTest.java

@@ -1,10 +1,11 @@
 package jenkins.util;
 
-import org.junit.Test;
+import org.junit.jupiter.api.Test;
 import org.jvnet.hudson.test.Issue;
 
-import static org.junit.Assert.assertFalse;
+import static org.junit.jupiter.api.Assertions.assertFalse;
-import static org.junit.Assert.assertTrue;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
 
 public class UrlHelperTest {