[Demonstration 1]

[Buggy Method]
@Test
public void testLookupUpstreamImapServerNoAccount() throws Exception {
    LdapProvisioning mockProvisioning = PowerMock.createMock(LdapProvisioning.class);
    EasyMock.expect(mockProvisioning.get(Key.AccountBy.name, QUSER)).andReturn(null);
    EasyMock.expect(mockProvisioning.getConfig()).andReturn(config).anyTimes();
    Provisioning.setInstance(mockProvisioning);
    PowerMock.mockStatic(Provisioning.class);
    handler = Whitebox.newInstance(NginxLookupExtension.NginxLookupHandler.class);
    Whitebox.setInternalState(handler, "prov", mockProvisioning);
    PowerMock.mockStatic(ImapLoadBalancingMechanism.class);
    PowerMock.suppress(PowerMock.constructor(ImapLoadBalancingMechanism.class));
    AttributeManager mockAttributeManager = PowerMock.createMock(AttributeManager.class);
    EasyMock.expect(mockAttributeManager.isEphemeral("zimbraImapLoadBalancingAlgorithm")).andReturn(false);
    EasyMock.expect(mockAttributeManager.getAttributeInfo("zimbraImapLoadBalancingAlgorithm")).andReturn(null);
    Whitebox.setInternalState(config, "mAttrMgr", mockAttributeManager);
    NginxLookupExtension.NginxLookupRequest request = Whitebox.newInstance(NginxLookupExtension.NginxLookupRequest.class);
    Whitebox.setInternalState(request, "user", QUSER);
    Whitebox.setInternalState(request, "httpReq", mockServletReq);
    PowerMock.replayAll();
    Server server = Whitebox.invokeMethod(handler, "lookupUpstreamImapServer", request);
    assertEquals("Server objects should be null", null, server);
    PowerMock.verifyAll();
}

[Buggy Hunk]
Server server = Whitebox.invokeMethod(handler, "lookupUpstreamImapServer", request);

[Patch]
Pair<Server, Boolean> server = Whitebox.invokeMethod(handler, "lookupUpstreamImapServer", request);

[Demonstration 2]

[Buggy Method]
@Test
public void testListBlobIds() throws Exception {
    expect(mockStore.openHDFSConnection()).andReturn(mockFs);
    expect(mockFs.listStatus((Path) anyObject())).andReturn(createTestFileStatus()).times(2);
    expect(mockStore.getId()).andReturn(URI.create("hdfs://localhost:9000/")).times(2);
    replay(mockStore, mockFs);
    HDFSBlobStoreConnection connection = createTestConnection();
    HDFSIdIterator it = (HDFSIdIterator) connection.listBlobIds("/");
    assertNotNull(it);
}

[Buggy Hunk]
expect(mockStore.openHDFSConnection()).andReturn(mockFs);

[Patch]
expect(mockStore.getFilesystem()).andReturn(mockFs);

[Demonstration 3]

[Buggy Method]
public static <TActual extends IOrderedIterable<T>, T> OrderedIterableAssert<TActual, T> AssertThat(@NullFeasible final TActual actual) {
    return new OrderedIterableAssert<TActual, T>(actual);
}

[Buggy Hunk]
OrderedIterableAssert<TActual, T> AssertThat(@NullFeasible final TActual actual) {

[Patch]
AbstractOrderedIterableAssert<?, TActual, T> AssertThat(@NullFeasible final TActual actual) {