How to run cucumber tests from a java TestRunner Class

Question

Working with cucumber-groovy-example

result:

/opt/gradle/gradle-2.7/bin/gradle clean cucumber uberJar
:clean
:compileJava
warning: [options] bootstrap class path not set in conjunction with -source 1.6
1 warning
:compileGroovy UP-TO-DATE
:processResources UP-TO-DATE
:classes
:jar
:startScripts
:distTar
:distZip
:assemble
:cucumber
# language: en
Feature: Division
  In order to avoid silly mistakes
  Cashiers must be able to calculate a fraction
SLF4J: Failed to load class "org.slf4j.impl.StaticLoggerBinder".
SLF4J: Defaulting to no-operation (NOP) logger implementation
SLF4J: See http://www.slf4j.org/codes.html#StaticLoggerBinder for further details.

  @important
  Scenario: Regular numbers                    # calc/division.feature:7
    Given I have entered 3 into the calculator # CalculatorSteps.groovy:31
    And I have entered 2 into the calculator   # CalculatorSteps.groovy:31
    When I press divide                        # CalculatorSteps.groovy:39
    Then the stored result should be 1.5       # CalculatorSteps.groovy:43

  Scenario: More numbers                       # calc/division.feature:13
    Given I have entered 6 into the calculator # CalculatorSteps.groovy:31
    And I have entered 3 into the calculator   # CalculatorSteps.groovy:31
    When I press divide                        # CalculatorSteps.groovy:39
    Then the stored result should be 2.0       # CalculatorSteps.groovy:43

2 Scenarios (2 passed         )
8 Steps (8 passed         )
0m0.186s

:uberJar

BUILD SUCCESSFUL

Total time: 19.643 secs

This build could be faster, please consider using the Gradle Daemon: https://docs.gradle.org/2.7/userguide/gradle_daemon.html

How can i run the same tests from within a Java file: e.g.

src/main/java/calc/TestRunner.java

import cucumber.api.CucumberOptions;
import cucumber.api.junit.Cucumber;
import org.junit.runner.RunWith;
import org.junit.runner.notification.Failure;

@RunWith(Cucumber.class)
@CucumberOptions(format = {"pretty"}, monochrome=true)

public class TestRunner {

                public static void main(String[] args) {
                                     System.out.println("dummy main java");
// I want to run the tests from within the jar file

                                          }
}

so that when i do java -jar build/distributions/cucumber-jvm-groovy-example.jar

i should get the same result as when i use gradle to run the tests via command line

i used the following Java Class:

import org.junit.*;
import org.junit.runner.JUnitCore;
import org.junit.runner.Result;
import org.junit.runner.notification.Failure;
import cucumber.api.CucumberOptions;
import cucumber.api.junit.Cucumber;
import org.junit.runner.RunWith;
import java.util.ArrayList;
import java.util.List;
import org.junit.runner.notification.Failure;

@RunWith(Cucumber.class)
@CucumberOptions(format = {"pretty"}, monochrome=true)

public class TestRunner {

        public static void main(String[] args) {
             System.out.println("dummy main java");
        JUnitCore.main("cucumberTest.TestRunner");
    }
}

but got the exception:

  initializationError(org.junit.runner.JUnitCommandLineParseResult)
java.lang.IllegalArgumentException: Could not find class [cucumberTest.TestRunner]
        at org.junit.runner.JUnitCommandLineParseResult.parseParameters(JUnitCommandLineParseResult.java:102)
        at org.junit.runner.JUnitCommandLineParseResult.parseArgs(JUnitCommandLineParseResult.java:50)
        at org.junit.runner.JUnitCommandLineParseResult.parse(JUnitCommandLineParseResult.java:44)
        at org.junit.runner.JUnitCore.runMain(JUnitCore.java:72)
        at org.junit.runner.JUnitCore.main(JUnitCore.java:36)
        at TestRunner.main(TestRunner.java:19)
Caused by: java.lang.ClassNotFoundException: cucumberTest.TestRunner

Which makes me to think that JUnitCore.main() needs a class name as argument

Answer 1

One way is to use the command line runner. Java class Runtime allows you to execute command line from within Java. The key is cucumber.api.cli.Main.

Something like this:

task cucumber() {
dependsOn assemble, compileTestJava
doLast {
    javaexec {
        main = "cucumber.api.cli.Main"
        classpath = configurations.cucumberRuntime + sourceSets.main.output + sourceSets.test.output
        args = ['--plugin', 'pretty', '--glue', 'gradle.cucumber', 'src/test/resources']
        }
    }
}