/**
 * Function attach file to email
 */
public PageReference attachFileToEmail() {

    // In case have file 
    if(attachment.Name != null) {
        // Get parentID
        EmailTemplate parentTemplate = [SELECT Id FROM EmailTemplate LIMIT 1];

        // Set ParentId and Description
        attachment.ParentId = parentTemplate.Id;
        try {
            // Insert file
            insert attachment;

            // Clear body file
            attachment.Body = null;

            if(attachment.Id != null) {
                uploadedAttachments.add(attachment);
            }
        } catch (DMLException e) {
            ApexPages.addMessage(new ApexPages.message(ApexPages.severity.ERROR,UPDATE_FILE_FAILD_ERROR_MESSAGE));
        } finally {
            attachment = new Attachment(); 
        } 
    } else {
            ApexPages.addMessage(new ApexPages.message(ApexPages.severity.ERROR,NO_CHOSE_FILE_ERROR_MESSAGE));
    } 

    return null;

}

My function:

My unit test:

/**
 * attachFileToEmail test
 * Insert success
 */
@isTest
static void AttachFileToEmailSuccessTestCase1() {
    // Create data
    Task[] results;
    BulkEmailSenderControllerTest mgr = new BulkEmailSenderControllerTest();
    BulkEmailSenderController controller = new BulkEmailSenderController();
    mgr.createEmailTemplateData();

    // Create data
    controller.attachment.Name='Unit Test Attachment';
    Blob bodyBlob=Blob.valueOf('Unit Test Attachment Body');
    controller.attachment.body = bodyBlob;
    controller.attachment.parentId = [SELECT Id FROM EmailTemplate LIMIT 1].Id;

    // Running test
    Test.startTest();

    controller.attachFileToEmail();

    Test.stopTest();

    // Compare
    System.assertEquals(1, controller.uploadedAttachments.size());
}

When I run test in Eclipse, this unit test is pass . However on Developer Console Tool is failed with message (System.AssertException: Assertion Failed: Expected: 1, Actual: 0).

Please help my problem.