Python 如何在Django功能测试中触发空值验证？

我是Django的新手，现在正在阅读“使用Python进行测试驱动开发”的学习手册。 但是，当我想要测试空值验证时，单元测试是可以的，但是功能测试失败了

我现在使用的是Django 2.1，Python3。我已经尽力检查了问题的原因，但是仍然没有通过功能测试

models.py

...
class Item(models.Model):
    text = models.TextField(default='')
    list = models.ForeignKey(List, default=None, on_delete=models.CASCADE)

views.py

...
def new_list(request):
    list_ = List.objects.create()
    item = Item.objects.create(text=request.POST['item_text'],list=list_)
    try:
        item.full_clean()
        item.save()
    except ValidationError:
        list_.delete()
        error = "You can't have an empty list item"
        return render(request, 'home.html', {"error": error})

    return redirect(list_)

test_views.py（单元测试成功）

测试列表项目验证.py（功能测试失败）

base.html（所有html文件都从此扩展）

。。。
{%if错误%}
{{error}}
{%endif%}

---

我希望单元测试和功能测试都是正确的，但实际结果是单元测试通过了，但功能测试失败了。这本书很棒。我自己读。我相信这是你缺少的部分：

def test_cannot_add_empty_list_items(self):
    # Edith goes to the home page and accidentally tries to submit
    # an empty list item. She hits Enter on the empty input box
    self.browser.get(self.live_server_url)
    self.get_item_input_box().send_keys(Keys.ENTER)

    '''
    If you keep reading a little farther, it should tell you that modern browsers
    will not submit forms when fields that are 'required' left are blank.
    '''
    # The browser intercepts the request, and does not load the
    # list page
    self.wait_for(lambda: self.browser.find_elements_by_css_selector(
        '#id_text:invalid'  
    ))

如果你继续往下读，它会告诉你，“当

必填字段保留为空时，现代浏览器不会提交
表单
。它会给你上面的代码修改

...
def test_cannot_add_empty_list_items(self):
    self.browser.get(self.live_server_url)
    self.browser.find_element_by_id('id_new_item').send_keys(Keys.ENTER)
    error = self.browser.find_element_by_css_selector('.has-error')
    self.assertEqual(error.text, "You can't have an empty list item")

...
{% if error %}
    <div class="form-group has-error">
        <span class="help-block">{{ error }}</span>
    </div>
{% endif %}

def test_cannot_add_empty_list_items(self):
    # Edith goes to the home page and accidentally tries to submit
    # an empty list item. She hits Enter on the empty input box
    self.browser.get(self.live_server_url)
    self.get_item_input_box().send_keys(Keys.ENTER)

    '''
    If you keep reading a little farther, it should tell you that modern browsers
    will not submit forms when fields that are 'required' left are blank.
    '''
    # The browser intercepts the request, and does not load the
    # list page
    self.wait_for(lambda: self.browser.find_elements_by_css_selector(
        '#id_text:invalid'  
    ))