diff -r 000000000000 -r 6474c204b198 mobile/android/tests/background/junit3/src/fxa/authenticator/TestAccountPickler.java
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mobile/android/tests/background/junit3/src/fxa/authenticator/TestAccountPickler.java	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,120 @@
+/* Any copyright is dedicated to the Public Domain.
+   http://creativecommons.org/publicdomain/zero/1.0/ */
+
+package org.mozilla.gecko.background.fxa.authenticator;
+
+import org.mozilla.gecko.background.helpers.AndroidSyncTestCase;
+import org.mozilla.gecko.background.sync.TestSyncAccounts;
+import org.mozilla.gecko.fxa.FxAccountConstants;
+import org.mozilla.gecko.fxa.authenticator.AccountPickler;
+import org.mozilla.gecko.fxa.authenticator.AndroidFxAccount;
+import org.mozilla.gecko.fxa.login.Separated;
+import org.mozilla.gecko.fxa.login.State;
+import org.mozilla.gecko.sync.Utils;
+
+import android.accounts.Account;
+import android.accounts.AccountManager;
+import android.test.InstrumentationTestCase;
+import android.test.RenamingDelegatingContext;
+
+public class TestAccountPickler extends AndroidSyncTestCase {
+  private final static String FILENAME_PREFIX = "TestAccountPickler-";
+  private final static String PICKLE_FILENAME = "pickle";
+
+  public Account account;
+  public RenamingDelegatingContext context;
+  public AccountManager accountManager;
+
+  @Override
+  public void setUp() {
+    this.account = null;
+    // Randomize the filename prefix in case we don't clean up correctly.
+    this.context = new RenamingDelegatingContext(getApplicationContext(), FILENAME_PREFIX +
+        Math.random() * 1000001 + "-");
+    this.accountManager = AccountManager.get(context);
+  }
+
+  @Override
+  public void tearDown() {
+    if (this.account != null) {
+      deleteAccount(this, this.accountManager, this.account);
+      this.account = null;
+    }
+    this.context.deleteFile(PICKLE_FILENAME);
+  }
+
+  public static void deleteAccount(final InstrumentationTestCase test,
+      final AccountManager accountManager, final Account account) {
+    TestSyncAccounts.deleteAccount(test, accountManager, account);
+  }
+
+  private boolean accountsExist() {
+    // Note that we don't use FirefoxAccounts.firefoxAccountsExist because it unpickles.
+    return AccountManager.get(context).getAccountsByType(FxAccountConstants.ACCOUNT_TYPE).length > 0;
+  }
+
+  public AndroidFxAccount addDummyAccount() throws Exception {
+    final String email = "iu@fakedomain.io";
+    final State state = new Separated(email, "uid", false); // State choice is arbitrary.
+    final AndroidFxAccount account = AndroidFxAccount.addAndroidAccount(context, email,
+        "profile", "serverURI", "tokenServerURI", state);
+    assertNotNull(account);
+    assertTrue(accountsExist()); // Sanity check.
+    this.account = account.getAndroidAccount(); // To remove in tearDown() if we throw.
+    return account;
+  }
+
+  public void testPickleAndUnpickle() throws Exception {
+    final AndroidFxAccount inputAccount = addDummyAccount();
+    // Sync is enabled by default so we do a more thorough test by disabling it.
+    inputAccount.disableSyncing();
+
+    AccountPickler.pickle(inputAccount, PICKLE_FILENAME);
+
+    // unpickle adds an account to the AccountManager so delete it first.
+    deleteAccount(this, this.accountManager, inputAccount.getAndroidAccount());
+    assertFalse(accountsExist());
+
+    final AndroidFxAccount unpickledAccount =
+        AccountPickler.unpickle(context, PICKLE_FILENAME);
+    assertNotNull(unpickledAccount);
+    this.account = unpickledAccount.getAndroidAccount(); // To remove in tearDown().
+    assertAccountsEquals(inputAccount, unpickledAccount);
+  }
+
+  public void testDeletePickle() throws Exception {
+    final AndroidFxAccount account = addDummyAccount();
+    AccountPickler.pickle(account, PICKLE_FILENAME);
+
+    final String s = Utils.readFile(context, PICKLE_FILENAME);
+    assertNotNull(s);
+    assertTrue(s.length() > 0);
+
+    AccountPickler.deletePickle(context, PICKLE_FILENAME);
+    org.mozilla.gecko.background.sync.TestAccountPickler.assertFileNotPresent(
+        context, PICKLE_FILENAME);
+  }
+
+  private void assertAccountsEquals(final AndroidFxAccount expected,
+      final AndroidFxAccount actual) throws Exception {
+    // TODO: Write and use AndroidFxAccount.equals
+    // TODO: protected.
+    //assertEquals(expected.getAccountVersion(), actual.getAccountVersion());
+    assertEquals(expected.getProfile(), actual.getProfile());
+    assertEquals(expected.getAccountServerURI(), actual.getAccountServerURI());
+    assertEquals(expected.getAudience(), actual.getAudience());
+    assertEquals(expected.getTokenServerURI(), actual.getTokenServerURI());
+    assertEquals(expected.getSyncPrefsPath(), actual.getSyncPrefsPath());
+    assertEquals(expected.isSyncing(), actual.isSyncing());
+    assertEquals(expected.getEmail(), actual.getEmail());
+    assertStateEquals(expected.getState(), actual.getState());
+  }
+
+  private void assertStateEquals(final State expected, final State actual) throws Exception {
+    // TODO: Write and use State.equals. Thus, this is only thorough for the State base class.
+    assertEquals(expected.getStateLabel(), actual.getStateLabel());
+    assertEquals(expected.email, actual.email);
+    assertEquals(expected.uid, actual.uid);
+    assertEquals(expected.verified, actual.verified);
+  }
+}