IPV6 follow-up

src/main/java/org/jvnet/hudson/test/RealJenkinsRule.java

@@ -185,7 +185,7 @@ public final class RealJenkinsRule implements TestRule {
 
     private int timeout = Integer.getInteger("jenkins.test.timeout", new DisableOnDebug(null).isDebugging() ? 0 : 600);
 
-    private String host = httpListenAddress;
+    private String host = "localhost";
 
     Process proc;
 
@@ -292,13 +292,13 @@ public RealJenkinsRule withTimeout(int timeout) {
 
     /**
      * Sets a custom host name for the Jenkins root URL.
-     * <p>By default, this is the same as the {@link #httpListenAddress}.
-     * But you may wish to set it to something else that resolves to the loopback address,
+     * <p>By default, this is just {@code localhost}.
+     * But you may wish to set it to something else that resolves to localhost,
      * such as {@code some-id.127.0.0.1.nip.io}.
      * This is particularly useful when running multiple copies of Jenkins (and/or other services) in one test case,
      * since browser cookies are sensitive to host but not port and so otherwise {@link HttpServletRequest#getSession}
      * might accidentally be shared across otherwise distinct services.
-     * <p>Calling this method does <em>not</em> change the fact that Jenkins will be configured to listen only on the loopback address for security reasons
+     * <p>Calling this method does <em>not</em> change the fact that Jenkins will be configured to listen only on localhost for security reasons
      * (so others in the same network cannot access your system under test, especially if it lacks authentication).
      */
     public RealJenkinsRule withHost(String host) {

src/test/java/org/jvnet/hudson/test/RealJenkinsRuleTest.java

@@ -27,6 +27,7 @@
 import static org.hamcrest.MatcherAssert.assertThat;
 import static org.hamcrest.Matchers.arrayContainingInAnyOrder;
 import static org.hamcrest.Matchers.containsString;
+import static org.hamcrest.Matchers.instanceOf;
 import static org.hamcrest.Matchers.is;
 import static org.hamcrest.Matchers.nullValue;
 import static org.junit.Assert.assertEquals;
@@ -53,6 +54,8 @@
 import java.io.IOException;
 import java.io.UncheckedIOException;
 import java.net.HttpURLConnection;
+import java.net.Inet6Address;
+import java.net.InetAddress;
 import java.nio.charset.StandardCharsets;
 import java.nio.file.Files;
 import java.util.concurrent.atomic.AtomicReference;
@@ -92,6 +95,14 @@ private static void _smokes(JenkinsRule r) throws Throwable {
         assertEquals(rr.getUrl().toExternalForm(), rr.runRemotely(RealJenkinsRuleTest::_getJenkinsUrlFromRemote));
     }
 
+    @Test public void ipv6() throws Throwable {
+        // Use -Djava.net.preferIPv6Addresses=true if dualstack
+        assumeThat(InetAddress.getLoopbackAddress(), instanceOf(Inet6Address.class));
+        rr.withHost("::1").startJenkins();
+        var externalForm = rr.getUrl().toExternalForm();
+        assertEquals(externalForm, rr.runRemotely(RealJenkinsRuleTest::_getJenkinsUrlFromRemote));
+    }
+
     @Test public void testThrowsException() {
         assertThat(assertThrows(RealJenkinsRule.StepException.class, () -> rr.then(RealJenkinsRuleTest::throwsException)).getMessage(),
             containsString("IllegalStateException: something is wrong"));