apacheGH-283: Add a test verifying the number of password prompts

Author: tomaswolf

sshd-core/src/test/java/org/apache/sshd/client/ClientTest.java

@@ -1342,6 +1342,68 @@ public String getUpdatedPassword(ClientSession clientSession, String prompt, Str
         assertNull("Session closure not signalled", clientSessionHolder.get());
     }
 
+    @Test // See GH-283
+    public void testPasswordPrompts() throws Exception {
+        CoreModuleProperties.PASSWORD_PROMPTS.set(client, 1);
+
+        client.setUserAuthFactories(Collections.singletonList(UserAuthKeyboardInteractiveFactory.INSTANCE));
+        client.start();
+
+        try (ClientSession session = client.connect(getCurrentTestName(), TEST_LOCALHOST, port).verify(CONNECT_TIMEOUT)
+                .getSession()) {
+            assertNotNull("Client session creation not signalled", clientSessionHolder.get());
+            AtomicInteger count = new AtomicInteger();
+            session.setUserInteraction(new UserInteraction() {
+                @Override
+                public boolean isInteractionAllowed(ClientSession session) {
+                    return true;
+                }
+
+                @Override
+                public void serverVersionInfo(ClientSession clientSession, List<String> lines) {
+                    assertSame("Mismatched server version info session", session, clientSession);
+                }
+
+                @Override
+                public void welcome(ClientSession clientSession, String banner, String lang) {
+                    assertSame("Mismatched welcome session", session, clientSession);
+                }
+
+                @Override
+                public String[] interactive(ClientSession clientSession, String name, String instruction, String lang,
+                        String[] prompt, boolean[] echo) {
+                    assertSame("Mismatched interactive session", session, clientSession);
+                    int n = count.incrementAndGet();
+                    if (n == 1) {
+                        return new String[] { "bogus" };
+                    }
+                    return new String[] { getCurrentTestName() };
+                }
+
+                @Override
+                public String getUpdatedPassword(ClientSession clientSession, String prompt, String lang) {
+                    throw new UnsupportedOperationException("Unexpected call");
+                }
+            });
+
+            AuthFuture future = session.auth();
+            assertTrue("Failed to complete authentication on time", future.await(CLOSE_TIMEOUT));
+            assertTrue("Authentication should have failed", future.isFailure());
+            assertEquals("Mismatched authentication attempts count", 1, count.get());
+            count.set(0);
+            CoreModuleProperties.PASSWORD_PROMPTS.set(client, 2);
+            future = session.auth();
+            assertTrue("Failed to complete authentication on time", future.await(CLOSE_TIMEOUT));
+            assertFalse("Authentication should not have failed", future.isFailure());
+            assertTrue("Authentication should have succeeded", future.isSuccess());
+            assertEquals("Mismatched authentication attempts count", 2, count.get());
+        } finally {
+            client.stop();
+        }
+
+        assertNull("Session closure not signalled", clientSessionHolder.get());
+    }
+
     @Test
     public void testKeyboardInteractiveInSessionUserInteractiveFailure() throws Exception {
         final int maxPrompts = 3;