From 0408ee5b946142da9457b5bf596cb84d33d409e3 Mon Sep 17 00:00:00 2001
From: Andy Stadler <stadler@google.com>
Date: Fri, 25 Mar 2011 15:08:34 -0700
Subject: [PATCH] DO NOT MERGE - Fix NPE in pop3 checkcapabilities

* This happens if an open fails immediately (error message in the
  initial banner) followed by a checkSettings.
* The fix is to harden checkSettings to force a clean connection
  every time.

Bug: 2170147
Backport of: If7403bf517477d2b03b21d71caab511fe45e234c

Change-Id: Ia6cc0e3ab0c8a8a78b5d8b8fb7b8ba4b4cdd3ef2
---
 .../android/email/mail/store/Pop3Store.java   |  4 ++
 .../email/mail/store/Pop3StoreUnitTests.java  | 37 +++++++++++++++++--
 2 files changed, 38 insertions(+), 3 deletions(-)

diff --git a/src/com/android/email/mail/store/Pop3Store.java b/src/com/android/email/mail/store/Pop3Store.java
index 9990fde5b..7e6480d01 100644
--- a/src/com/android/email/mail/store/Pop3Store.java
+++ b/src/com/android/email/mail/store/Pop3Store.java
@@ -171,6 +171,10 @@ public class Pop3Store extends Store {
     @Override
     public void checkSettings() throws MessagingException {
         Pop3Folder folder = new Pop3Folder("INBOX");
+        // Close any open or half-open connections - checkSettings should always be "fresh"
+        if (mTransport.isOpen()) {
+            folder.close(false);
+        }
         try {
             folder.open(OpenMode.READ_WRITE, null);
             folder.checkSettings();
diff --git a/tests/src/com/android/email/mail/store/Pop3StoreUnitTests.java b/tests/src/com/android/email/mail/store/Pop3StoreUnitTests.java
index 4a210262d..75714f3d1 100644
--- a/tests/src/com/android/email/mail/store/Pop3StoreUnitTests.java
+++ b/tests/src/com/android/email/mail/store/Pop3StoreUnitTests.java
@@ -21,12 +21,12 @@ import com.android.email.mail.Address;
 import com.android.email.mail.FetchProfile;
 import com.android.email.mail.Flag;
 import com.android.email.mail.Folder;
-import com.android.email.mail.Message;
-import com.android.email.mail.MessagingException;
-import com.android.email.mail.Transport;
 import com.android.email.mail.Folder.FolderType;
 import com.android.email.mail.Folder.OpenMode;
+import com.android.email.mail.Message;
 import com.android.email.mail.Message.RecipientType;
+import com.android.email.mail.MessagingException;
+import com.android.email.mail.Transport;
 import com.android.email.mail.internet.MimeMessage;
 import com.android.email.mail.transport.MockTransport;
 
@@ -204,6 +204,37 @@ public class Pop3StoreUnitTests extends AndroidTestCase {
         }
     }
 
+    /**
+     * Test a strange case that causes open to proceed without mCapabilities
+     *  open - fail with "-" error code
+     *  then check capabilities
+     */
+    public void testCheckSettingsCapabilities() throws MessagingException {
+
+        MockTransport mockTransport = openAndInjectMockTransport();
+
+        // First, preload an open that fails for some reason
+        mockTransport.expect(null, "-ERR from the Mock Transport.");
+
+        // And watch it fail
+        try {
+            Pop3Store.Pop3Folder folder = mStore.new Pop3Folder("INBOX");
+            folder.open(OpenMode.READ_WRITE, null);
+            fail("Should have thrown exception");
+        } catch (MessagingException me) {
+            // Expected - continue.
+        }
+
+        // Now try again (assuming a slightly different connection setup - successful)
+        // Note, checkSettings is going to try to close the connection again, so we expect
+        // one extra QUIT before we spin it up again
+        mockTransport.expect("QUIT", "");
+        mockTransport.expectClose();
+        setupOpenFolder(mockTransport, 0, "UIDL");
+        mockTransport.expect("QUIT", "");
+        mStore.checkSettings();
+    }
+
     /**
      * Test small Store & Folder functions that manage folders & namespace
      */