Set loopback users back to initial value after test

(cherry picked from commit 46b245f)

Author: acogoluegnes

Diff for: src/test/java/com/rabbitmq/client/test/functional/ConnectionRecovery.java

@@ -23,7 +23,6 @@
 import com.rabbitmq.client.test.BrokerTestCase;
 import com.rabbitmq.client.test.TestUtils;
 import com.rabbitmq.tools.Host;
-import org.junit.jupiter.api.Disabled;
 import org.junit.jupiter.api.Test;
 
 import java.io.IOException;
@@ -368,7 +367,6 @@ private void testClientNamedQueueRecoveryWith(String q, boolean noWait) throws I
     }
 
     // bug 26552
-    @Disabled
     @Test public void clientNamedTransientAutoDeleteQueueAndBindingRecovery() throws IOException, InterruptedException, TimeoutException {
         String q   = UUID.randomUUID().toString();
         String x   = "tmp-fanout";

Diff for: src/test/java/com/rabbitmq/client/test/server/LoopbackUsers.java

@@ -48,14 +48,26 @@ public class LoopbackUsers {
     @Test public void loopback() throws IOException, TimeoutException {
 	      if (!Host.isOnDocker()) {
             String addr = findRealIPAddress().getHostAddress();
-            assertGuestFail(addr);
-            Host.rabbitmqctl("eval 'application:set_env(rabbit, loopback_users, []).'");
-            assertGuestSucceed(addr);
-            Host.rabbitmqctl("eval 'application:set_env(rabbit, loopback_users, [<<\"guest\">>]).'");
-            assertGuestFail(addr);
+            String initialValue = getLoopbackUsers();
+            try {
+                setLoopbackUsers("[]");
+                assertGuestSucceed(addr);
+                setLoopbackUsers("[<<\"guest\">>]");
+                assertGuestFail(addr);
+            } finally {
+                setLoopbackUsers(initialValue);
+            }
         }
     }
 
+    private static String getLoopbackUsers() throws IOException {
+        return Host.rabbitmqctl("eval '{ok, V} = application:get_env(rabbit, loopback_users), V.'").output();
+    }
+
+    private static void setLoopbackUsers(String value) throws IOException {
+        Host.rabbitmqctl(String.format("eval 'application:set_env(rabbit, loopback_users, %s).'", value));
+    }
+
     private void assertGuestSucceed(String addr) throws IOException, TimeoutException {
         succeedConnect("guest", addr);
         succeedConnect("guest", "localhost");

Diff for: src/test/java/com/rabbitmq/tools/Host.java

@@ -80,7 +80,7 @@ public static ProcessState executeCommand(String command) throws IOException
         return new ProcessState(pr, inputState, errorState);
     }
 
-    static class ProcessState {
+    public static class ProcessState {
 
         private final Process process;
         private final InputStreamPumpState inputState;
@@ -93,7 +93,7 @@ static class ProcessState {
             this.errorState = errorState;
         }
 
-        private String output() {
+        public String output() {
             return inputState.buffer.toString();
         }