行为：使用动态示例编写场景大纲

Question

小黄瓜/行为Examples

Gherkin 语法特性test automation using examples:

Feature: Scenario Outline (tutorial04)

  Scenario Outline: Use Blender with <thing>
    Given I put "<thing>" in a blender
    When I switch the blender on
    Then it should transform into "<other thing>"

    Examples: Amphibians
        | thing         | other thing |
        | Red Tree Frog | mush        |
        | apples        | apple juice |

    Examples: Consumer Electronics
        | thing         | other thing |
        | iPhone        | toxic waste |
        | Galaxy Nexus  | toxic waste |

测试套件将运行四次，每个示例运行一次，结果类似于：

我的问题

如何使用Examples 部分中的机密数据进行测试？例如，我想使用用户 ID 或 SSN 号测试内部 API，而不将数据硬编码在功能文件中。

有没有办法从外部源动态加载Examples？

更新：在behave项目上打开了github issue。

Answer 1

我想出了另一个解决方案（behave-1.2.6）：

我设法使用before_feature 为场景大纲动态创建示例。

给定一个功能文件 (x.feature)：

Feature: Verify squared numbers

  Scenario Outline: Verify square for <number>
    Then the <number> squared is <result>

Examples: Static
  | number | result |
  |   1    |    1   | 
  |   2    |    4   |
  |   3    |    9   |
  |   4    |   16   |

  # Use the tag to mark this outline
  @dynamic
  Scenario Outline: Verify square for <number>
    Then the <number> squared is <result>

Examples: Dynamic
  | number | result |
  |   .    |    .   | 

还有步骤文件（steps/x.step）：

from behave import step

@step('the {number:d} squared is {result:d}')
def step_impl(context, number, result):
    assert number*number == result

诀窍是在environment.py 中使用before_feature，因为它已经将示例表解析为场景大纲，但尚未从大纲生成场景。

import behave
import copy

def before_feature(context, feature):
    features = (s for s in feature.scenarios if type(s) == behave.model.ScenarioOutline and
                'dynamic' in s.tags)
    for s in features:
        for e in s.examples:
            orig = copy.deepcopy(e.table.rows[0])
            e.table.rows = []
            for num in range(1,5):
                n = copy.deepcopy(orig)
                # This relies on knowing that the table has two rows.
                n.cells = ['{}'.format(num), '{}'.format(num*num)]
                e.table.rows.append(n)

这仅适用于带有@dynamic 标记的场景大纲。

结果是：

behave -k --no-capture
Feature: Verify squared numbers # features/x.feature:1

  Scenario Outline: Verify square for 1 -- @1.1 Static  # features/x.feature:8
    Then the 1 squared is 1                             # features/steps/x.py:3

  Scenario Outline: Verify square for 2 -- @1.2 Static  # features/x.feature:9
    Then the 2 squared is 4                             # features/steps/x.py:3

  Scenario Outline: Verify square for 3 -- @1.3 Static  # features/x.feature:10
    Then the 3 squared is 9                             # features/steps/x.py:3

  Scenario Outline: Verify square for 4 -- @1.4 Static  # features/x.feature:11
    Then the 4 squared is 16                            # features/steps/x.py:3

  @dynamic
  Scenario Outline: Verify square for 1 -- @1.1 Dynamic  # features/x.feature:19
    Then the 1 squared is 1                              # features/steps/x.py:3

  @dynamic
  Scenario Outline: Verify square for 2 -- @1.2 Dynamic  # features/x.feature:19
    Then the 2 squared is 4                              # features/steps/x.py:3

  @dynamic
  Scenario Outline: Verify square for 3 -- @1.3 Dynamic  # features/x.feature:19
    Then the 3 squared is 9                              # features/steps/x.py:3

  @dynamic
  Scenario Outline: Verify square for 4 -- @1.4 Dynamic  # features/x.feature:19
    Then the 4 squared is 16                             # features/steps/x.py:3

1 feature passed, 0 failed, 0 skipped
8 scenarios passed, 0 failed, 0 skipped
8 steps passed, 0 failed, 0 skipped, 0 undefined
Took 0m0.005s

这依赖于将具有正确形状的示例表作为最终表，在我的示例中，有两行。我也不大惊小怪地创建新的behave.model.Row 对象，我只是从表中复制一个并更新它。为了更加丑陋，如果您使用的是文件，则可以将文件名放在示例表中。

Answer 2

来到这里寻找其他东西，但由于我以前和 Cucumber 有过类似的情况，也许有人也会最终解决这个问题，寻找可能的解决方案。我解决这个问题的方法是使用BDD variables，稍后我可以在运行时在我的step_definitions 中处理它。在我的 python 代码中，我可以检查 Gherkin 变量的值并将其映射到需要的值。

对于这个例子：

Scenario Outline: Use Blender with <thing>
     Given I put "<thing>" in a blender
     When I switch the blender on
     Then it should transform into "<other thing>"

    Examples: Amphibians
        | thing         | other thing            |
        | Red Tree Frog | mush                   |
        | iPhone        | data.iPhone.secret_key | # can use .yaml syntax here as well

会翻译成这样的 step_def 代码：

@given('I put "{thing}" in a blender')
def step_then_should_transform_into(context, other_thing):   
  if other_thing == BddVariablesEnum.SECRET_KEY: 
    basic_actions.load_secrets(context, key)

所以你所要做的就是定义好DSL层。

Answer 3

关于在测试中使用 SSN 号码的问题，我只是 use fake SSNs 而不担心我会泄露人们的私人信息。

好的，但是更大的问题呢？您想使用场景大纲和无法放入功能文件的示例。每当我遇到这个问题时，我所做的就是描述我需要的数据，并让步骤实现 create 用于测试的实际数据集或 fetch 来自现有测试数据库的数据集。

Scenario Outline: Accessing the admin interface
  Given a user who <status> an admin has logged in
  Then the user <ability> see the admin interface

Examples: Users
  | status | ability |
  | is     | can     |
  | is not | cannot  |

无需在功能文件中显示有关用户的任何详细信息。步骤实现负责根据status 的值创建或获取适当类型的用户。