cucumber自动化测试官方教程
来源：http://www.uml.org.cn/
安装
cucumber是一款测试工具。可用于大多数主流编程语言。比如JAVA、JS、Ruby、C++、Lua、Android、Kotlin、C#/F#、PHP、Python、Go、Groovy、Scala等等。其中JAVA、JS、Ruby的代码托管在cucumber下。官方建议选择与生产代码相同的平台或编程语言的实现。本文主要是JAVA平台下的介绍教程。使用方法非常简单，创建一个mvn工程，在pom.xml文件引入以下依赖即可。
<dependency><groupId>io.cucumber</groupId><artifactId>cucumber-java8</artifactId><version>4.2.0</version><scope>test</scope></dependency> |
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也可以根据骨架创建cucumber项目。
创建一个空的Cucumber项目
我们首先使用cucumber- prototype Maven插件创建一个新项目目录。打开终端，转到要创建项目的目录（比如本文是hellocucumber)，运行以下命令:
mvn archetype:generate \-DarchetypeGroupId=io.cucumber \-DarchetypeArtifactId=cucumber-archetype \-DarchetypeVersion=2.3.1.2 \-DgroupId=hellocucumber \-DartifactId=hellocucumber \-Dpackage=hellocucumber \-Dversion=1.0.0-SNAPSHOT \-DinteractiveMode=false |
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你应该得到如下结果:
[INFO] Project created from Archetype in dir:hellocucumber/cucumber[INFO] -------------------------------------[INFO] BUILD SUCCESS[INFO] ------------------------------------- |
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切换到刚才运行命令创建的目录:
cd hellocucumber |
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在IntelliJ IDEA(或者eclipse都行）中打开项目:
文件->打开…->(选择pom.xml)
选择Open as Project
现在，您已经安装了一个简单的Cucumber项目。
验证cucumber安装
mvn test |
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您应该看到如下内容:
------------------------------------T E S T S------------------------------------Running hellocucumber.RunCucumberTestNo features found at [classpath:hellocucumber]0 Scenarios0 Steps0m0.004sTests run: 0, Failures: 0, Errors: 0, Skipped: 0,Time elapsed: 0.541 secResults :Tests run: 0, Failures: 0, Errors: 0, Skipped: 0[INFO] -----------------------------------------[INFO] BUILD SUCCESS[INFO] ----------------------------------------- |
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Cucumber的输出告诉我们它没有找到任何可以运行的东西。
写一个Scenario（场景）
当我们使用Cucumber进行行为驱动开发时，我们使用具体的例子来指定我们希望软件做什么。 Scenario是在生产代码之前编写的。它们以可执行规范的形式开始生命。随着生产代码的出现，场景扮演了事实文档和自动化测试的角色。
在Cucumber中，一个example称为Scenario。Scenario定义在.feature文件中，这些文件存储在src/test/resources/hellocucumber目录(或子目录)中。
一个具体的例子就是：星期天不是星期五。
创建一个名为src/test/resources/ hellocucumber/is_it_friday_yet.feature的文件， 文件包括以下内容:
Feature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't FridayGiven today is SundayWhen I ask whether it's Friday yetThen I should be told "Nope" |
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这个文件的第一行以关键字'''Feature'''开始:后面跟着一个名称。最好使用与文件名类似的名称。
第二行是对该特性的简要描述。Cucumber并不执行这一行，它只是一个文档。
第4行，场景:Sunday is not Friday是一个scenario，它是说明软件应该如何工作的具体示例。
最后三行以Given开头，When和Then是我们的场景的步骤。这就是Cucumber将要执行的操作。
看一个未定义的scenario报告
现在我们有了一个场景，我们可以让Cucumber执行它：
mvn test |
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Cucumber告诉我们有一个undefined的场景和三个undefined的步骤。它还建议我们使用一些代码片段来define这些步骤:
-------------------------------------T E S T S-------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't Friday # hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # nullWhen I ask whether it's Friday yet # nullThen I should be told "Nope" # null1 Scenarios (1 undefined)3 Steps (3 undefined)0m0.040sYou can implement missing steps with the snippets below:@Given("^today is Sunday$")public void today_is_Sunday() {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();}@When("^I ask whether it's Friday yet$")public void i_ask_whether_it_s_Friday_yet() {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();}@Then("^I should be told \"([^\"]*)\"$")public void i_should_be_told(String arg1) {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();} |
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复制以上未定义步骤的三个代码片段：
@Given("^today is Sunday$")public void today_is_Sunday() {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();}@When("^I ask whether it's Friday yet$")public void i_ask_whether_it_s_Friday_yet() {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();}@Then("^I should be told \"([^\"]*)\"$")public void i_should_be_told(String arg1) {// Write code here that turns the phrase aboveinto concrete actionsthrow new PendingException();} |
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并将它们粘贴到src/test/java/hellocucumber/steps.java中。
看一个pending的scenario报告
再次运行Cucumber: mvn test。这次的输出略有不同:
------------------------------------T E S T S------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't Friday # hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # Stepdefs.today_is_Sunday()cucumber.api.PendingException: TODO: implement meat hellocucumber.Stepdefs.today_is_Sunday(Stepdefs.java:12)at ?.today is Sunday(hellocucumber/is_it_friday_yet.feature:5)When I ask whether it's Friday yet # Stepdefs.i_ask_whether_it_s_Friday_yet()Then I should be told "Nope" #Stepdefs.i_should_be_told(String)1 Scenarios (1 pending)3 Steps (2 skipped, 1 pending)0m0.188scucumber.api.PendingException:TODO: implement meat hellocucumber.Stepdefs.today_is_Sunday(Stepdefs.java:12)at ?.today is Sunday(hellocucumber/is_it_friday_yet.feature:5) |
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Cucumber找到我们的步骤定义并执行它们。它们当前被标记为pending，这意味着我们需要让它们做一些有用的事情。
看一个falling的scenario报告
下一步是按照步骤定义中的注释所告诉我们的去做:
Write code here that turns thephrase above into concrete actions |
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尝试在代码中使用与步骤中相同的单词。
将步骤定义代码更改为:
package hellocucumber;import cucumber.api.java.en.Given;import cucumber.api.java.en.When;import cucumber.api.java.en.Then;import static org.junit.Assert.*;class IsItFriday {static String isItFriday(String today) {return null;}}public class Stepdefs {private String today;private String actualAnswer;@Given("^today is Sunday$")public void today_is_Sunday() {today = "Sunday";}@When("^I ask whether it's Friday yet$")public void i_ask_whether_is_s_Friday_yet() {actualAnswer = IsItFriday.isItFriday(today);}@Then("^I should be told \"([^\"]*)\"$")public void i_should_be_told(String expectedAnswer) {assertEquals(expectedAnswer, actualAnswer);}} |
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再次运行mvn test :
-------------------------------------T E S T S-------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't Friday # hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # Stepdefs.today_is_Sunday()When I ask whether it's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "Nope" # Stepdefs.i_should_be_told(String)java.lang.AssertionError: expected:<Nope> but was:<null>at org.junit.Assert.fail(Assert.java:88)at org.junit.Assert.failNotEquals(Assert.java:834)at org.junit.Assert.assertEquals(Assert.java:118)at org.junit.Assert.assertEquals(Assert.java:144)at hellocucumber.Stepdefs.i_should_be_told(Stepdefs.java:30)at ?.I should be told "Nope"(hellocucumber/is_it_friday_yet.feature:7)Failed scenarios:hellocucumber/is_it_friday_yet.feature:4# Sunday isn't Friday1 Scenarios (1 failed)3 Steps (1 failed, 2 passed)0m0.404s |
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这就是进步! 但前两步已经passing，最后一步却failing了。
看一个passing的scenario报告
让我们做最简单的事情来让场景通过。在本例中，这只是为了让我们的方法返回Nope :
static String isItFriday(String today) {return "Nope";} |
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再次运行mvn test:
-------------------------------------T E S T S-------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't Friday #hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # Stepdefs.today_is_Sunday()When I ask whether it's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "Nope"# Stepdefs.i_should_be_told(String)1 Scenarios (1 passed)3 Steps (3 passed)0m0.255s |
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恭喜你!这是第一个成功(passing)的Cucumber Scenario。
添加另一个失败的测试
下一件要测试的事情是，我们也会在周五得到正确的结果。
更新is-it-friday-yet.feature文件:
Feature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't FridayGiven today is SundayWhen I ask whether it's Friday yetThen I should be told "Nope"Scenario: Friday is FridayGiven today is FridayWhen I ask whether it's Friday yetThen I should be told "TGIF" |
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我们需要添加一个步骤定义，将today设置为“Friday”:
@Given("^today is Friday$")public void today_is_Friday() {this.today = "Friday";} |
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当我们运行这个测试时，它将失败。
Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Sunday isn't Friday# hellocucumber/isitfriday.feature:4Given today is "Sunday" # Stepdefs.today_is(String)When I ask whether is's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "Nope"# Stepdefs.i_should_be_told(String)Scenario: Friday is Friday# hellocucumber/is_it_friday.feature:9Given today is "Friday"# Stepdefs.today_is(String)When I ask whether is's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "TGIF"# Stepdefs.i_should_be_told(String)org.junit.ComparisonFailure:expected:<[TGIF]> but was:<[Nope]>at org.junit.Assert.assertEquals(Assert.java:115)at org.junit.Assert.assertEquals(Assert.java:144)at hellocucumber.Stepdefs.i_should_be_told(Stepdefs.java:26)at ?.I should be told "TGIF"(hellocucumber/is_it_friday.feature:12)org.junit.ComparisonFailure:Expected :TGIFActual :Nope<Click to see difference>at org.junit.Assert.assertEquals(Assert.java:115)at org.junit.Assert.assertEquals(Assert.java:144)at hellocucumber.Stepdefs.i_should_be_told(Stepdefs.java:26)at ?.I should be told "TGIF"(hellocucumber/is_it_friday.feature:12) |
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那是因为我们还没有实现逻辑!我们接着做。
让它通过
我们应该更新我们的语句来实际评估Today是否等于“Friday”。
static String isItFriday(String today) {if (today.equals("Friday")) {return "TGIF";}return "Nope";} |
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再次运行mvn test:
-------------------------------------T E S T S-------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario: Friday is Friday# hellocucumber/is_it_friday_yet.feature:4Given today is Friday # Stepdefs.today_is_Sunday()When I ask whether it's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "TGIF"# Stepdefs.i_should_be_told(String)Scenario: Sunday isn't Friday# hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # Stepdefs.today_is_Sunday()When I ask whether it's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "Nope"# Stepdefs.i_should_be_told(String)2 scenarios (2 passed)6 steps (6 passed)0m0.255s |
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使用变量和实例
所以，我们都知道一周中不止周日和周五。让我们更新我们的scenario以使用变量并评估更多的可能性。我们将使用变量和示例来计算星期五、星期天和其他任何时间! 更新is-it-friday-yet.feature文件。注意，当我们开始使用多个Examples时，我们是如何从一个Scenario切换到Scenario Outline的。
Feature: Is it Friday yet?Everybody wants to know when it's FridayScenario Outline: Today is or is not FridayGiven today is "<day>"When I ask whether it's Friday yetThen I should be told "<answer>"Examples:| day | answer || Friday | TGIF || Sunday | Nope || anything else! | Nope | |
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我们需要用一个以为字符串的步骤定义来替换today is Sunday和today is Friday的步骤定义。更新stepdefs.java文件如下:
package hellocucumber;import cucumber.api.java.en.Given;import cucumber.api.java.en.When;import cucumber.api.java.en.Then;import static org.junit.Assert.*;class IsItFriday {static String isItFriday(String today) {if (today.equals("Friday")) {return "TGIF";}return "Nope";}}public class Stepdefs {private String today;private String actualAnswer;@Given("^today is \"([^\"]*)\"$")public void today_is(String today) {this.today = today;}@When("^I ask whether it's Friday yet$")public void i_ask_whether_is_s_Friday_yet() {this.actualAnswer = IsItFriday.isItFriday(today);}@Then("^I should be told \"([^\"]*)\"$")public void i_should_be_told(String expectedAnswer) {assertEquals(expectedAnswer, actualAnswer);}} |
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再次执行mvn test:
-------------------------------------T E S T S-------------------------------------Running hellocucumber.RunCucumberTestFeature: Is it Friday yet?Everybody wants to know when it's FridayScenario Outline: Today is or is not Friday # hellocucumber/is_it_friday_yet.feature:4Given today is <day># hellocucumber/is_it_friday_yet.feature:5When I ask whether it's Friday yet # hellocucumber/is_it_friday_yet.feature:6Then I should be told <answer># hellocucumber/is_it_friday_yet.feature:7Scenario: Sunday isn't Friday# hellocucumber/is_it_friday_yet.feature:4Given today is Sunday # Stepdefs.today_is_Sunday()When I ask whether it's Friday yet # Stepdefs.i_ask_whether_is_s_Friday_yet()Then I should be told "Nope"# Stepdefs.i_should_be_told(String)Examples:| day | answer || "Friday" | "TGIF" || "Sunday" | "Nope" || "anything else!" | "Nope" |3 scenarios (3 passed)9 steps (9 passed)0m0.255s |
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重构
现在我们有了工作代码，我们应该做一些重构:
我们应该将isItFriday方法从测试代码移到生产代码中。 我们可以在某个时候从步骤定义中提取helper方法，用于我们在几个地方使用的方法。
星云测试
http://www.teststars.cc
奇林软件
http://www.kylinpet.com
联合通测
http://www.quicktesting.net
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