参数化是自动化测试的一种常用技巧，可以将测试代码中的某些输入使用参数来代替。以百度搜索功能为例，每次测试搜索场景，都需要测试不同的搜索内容，在这个过程里面，除了数据在变化，测试步骤都是重复的，这时就可以使用参数化的方式来解决测试数据变化，测试步骤不变的问题。
参数化就是把测试需要用到的参数写到数据集合里，让程序自动去这个集合里面取值，每条数据都生成一条对应的测试用例，直到集合里的值全部取完。
使用方法
使用 Appium 测试框架编写测试用例时，通常会结合单元测试框架一起使用。使用测试框架的参
- Python 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">@pytest.mark.parametrize("argvnames",argvalues) </pre>
- Java 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">@ParameterizedTest @ValueSource(strings = argvalues) </pre>
不同语言的单测框架支持的参数传递方式也不一样。一般情况，会在测试用例上添加一个装饰器，以python语言的 pytest 为例，在测试用例上添加参数化需要的装饰器 @pytest.mark.parametrize() ，这里需要传入两个参数 “argnamest” 与 “argvalues”，第一个参数需要一个或者多个变量来接收列表中的每组数据，第二个参数传递存储数据的列表。测试用例需要使用同名的字符串接收测试数据（与“argvnames”里面的名字一致），且列表有多少个元素就会生成并执行多个测试用例。下面示例使用使用参数化定义三组数据，每组数据都存放在一个元组中，分别将元组中的数据传入（test_input,expected）参数中，示例代码如下：
- Python 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">`# content of test_expectation.py
import pytest
@pytest.mark.parametrize("test_input,expected", [("3+5", 8), ("2+4", 6), ("6*9", 42)])
def test_eval(test_input, expected):
assert eval(test_input) == expected` </pre>
运行结果如下：
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">`...
test_expectation.py ..F
test_input = '6*9', expected = 42
@pytest.mark.parametrize("test_input,expected",
[("3+5", 8), ("2+4", 6), ("6*9", 42)])
def test_eval(test_input, expected):
assert eval(test_input) == expected
E AssertionError: assert 54 == 42
E + where 54 = eval('6*9')
test_expectation.py:6: AssertionError` </pre>
- Java 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">public class BookParamTest { @ParameterizedTest @MethodSource("intProvider") void testWithExplicitLocalMethodSource(int first,int second,int sum) { assertEquals(first + second , sum); } static Stream<Arguments> intProvider() { return Stream.of( arguments( 3 , 5 , 8), arguments( 3 , 5 , 6), arguments( 6 , 9 , 42) ); } } </pre>
运行结果如下：
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">`...
org.opentest4j.AssertionFailedError:
Expected :8
Actual :6
<Click to see difference>
at org.junit.jupiter.api.AssertionUtils.fail(AssertionUtils.java:55)
at org.junit.jupiter.api.AssertionUtils.failNotEqual(AssertionUtils.java:62)
at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:150)
at org.junit.jupiter.api.AssertEquals.assertEquals(AssertEquals.java:145)
at org.junit.jupiter.api.Assertions.assertEquals(Assertions.java:527)
...` </pre>
上面的运行结果可以看出，执行的三条测试用例分别对应三组数据，测试步骤完全相同，只是传入的测试数据发生了变化。
案例
使用“雪球”应用，打开雪球 APP，点击页面上的搜索输入框输入“alibaba”，然后在搜索联想出来的列表里面点击“阿里巴巴”，选择股票分类，获取股票类型为“BABA”的股票价格，最后验证价格在预期价格的 10%范围浮动，另一个搜索“小米”的结果数据测试步骤类似。
这个案例使用了参数化机制和 Hamcrest 断言机制，示例代码片断如下：
[图片上传失败...(image-a40bb3-1656485877938)]
参数化核心示例代码：
Python 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">`from appium import webdriver
import pytest
from hamcrest import *
class TestXueqiu:
# 省略...
# 参数化
@pytest.mark.parametrize("keyword, stock_type, expect_price", [
('alibaba', 'BABA', 170),
('xiaomi', '01810', 8.5)
])
def test_search(self, keyword, stock_type, expect_price):
# 点击搜索
self.driver.find_element_by_id("home_search").click()
# 向搜索框中输入keyword
self.driver.find_element_by_id(
"com.xueqiu.android:id/search_input_text"
).send_keys(keyword)
# 点击搜索结果
self.driver.find_element_by_id("name").click()
# 获取价格
price = float(self.driver.find_element_by_xpath(
"//*[contains(@resource-id, 'stockCode')\
and @text='%s']/../../..\
//*[contains(@resource-id, 'current_price')]"
% stock_type
).text)
# 断言
assert_that(price, close_to(expect_price, expect_price * 0.1))
...` </pre>
Java 版本
<pre class="copy-codeblocks" style="font-family: Consolas, Menlo, Monaco, "Lucida Console", "Liberation Mono", "DejaVu Sans Mono", "Bitstream Vera Sans Mono", "Courier New", monospace; font-size: 15.008px; display: block; position: relative; overflow: visible; color: rgb(34, 34, 34); font-style: normal; font-variant-ligatures: normal; font-variant-caps: normal; font-weight: 400; letter-spacing: normal; orphans: 2; text-align: start; text-indent: 0px; text-transform: none; widows: 2; word-spacing: 0px; -webkit-text-stroke-width: 0px; background-color: rgb(255, 255, 255); text-decoration-thickness: initial; text-decoration-style: initial; text-decoration-color: initial;">`import org.junit.jupiter.params.ParameterizedTest;
import org.junit.jupiter.params.provider.Arguments;
import org.junit.jupiter.params.provider.MethodSource;
import java.util.stream.Stream;
import static org.hamcrest.MatcherAssert.assertThat;
import static org.hamcrest.Matchers.closeTo;
import static org.junit.jupiter.params.provider.Arguments.arguments;
public class XueqiuTest {
// 省略...
@ParameterizedTest
@MethodSource
void testSearch(String keyword, String stockType, float expectPrice) {
//点击搜索
driver.findElement(By.id("home_search")).click();
//向搜索框中输入keyword
driver.findElement(By.id("com.xueqiu.android:id/search_input_text"\
)).sendKeys(keyword);
//点击搜索结果
driver.findElement(By.id("name")).click();
//获取价格
String format = String.format("//*[contains(@resource-id, \
'stockCode') and @text='%s']/../../..//*[contains(@resource-id,\
'current_price')]", stockType);
String text = driver.findElement(By.xpath(format)).getText();
double price = Double.parseDouble(text);
assertThat(price , closeTo(expectPrice,expectPrice * 0.1));
}
static Stream<Arguments> testSearch() {
return Stream.of(
arguments("alibaba", "BABA", 170),
arguments("xiaomi", "01810", 8.5)
);
}
}` </pre>
上面的代码，传入了两组测试数据，每组有三个数据分别为搜索关键词，股票类型，及股票价格。在执行测试用例时，分别将两组数据传入测试步骤中执行，对应搜索不同的关键词，使用 Hamcrest 来实现股票价格的断言。
获取更多相关资料戳：https://qrcode.ceba.ceshiren.com/link?name=article&project_id=qrcode&from=jianshu×tamp=1656485903&author=wuyue
