Gradle task check if property is defined

Question

I have a Gradle task that executes a TestNG test suite. I want to be able to pass a flag to the task in order to use a special TestNG XML suite file (or just use the default suite if the flag isn't set).

gradle test

... should run the default standard suite of tests

gradle test -Pspecial

... should run the special suite of tests

I've been trying something like this:

test {
    if (special) {
        test(testng_special.xml);
    }
    else {
        test(testng_default.xml);
    }
}

But I get a undefined property error. What is the correct way to go about this?

Answer 1

if (project.hasProperty('special'))

should do it.

Note that what you're doing to select a testng suite won't work, AFAIK: the test task doesn't have any test() method. Refer to https://discuss.gradle.org/t/how-to-run-acceptance-tests-with-testng-from-gradle/4107 for a working example:

test {
    useTestNG {
        suites 'src/main/resources/testng.xml'
    }
}

Answer 2

This worked for me:

test {
    if (properties.containsKey('special')) {
        test(testng_special.xml);
    }
    else {
        test(testng_default.xml);
    }
}

Answer 3

Here are 3 solutions for Kotlin DSL (build.gradle.kts):

val prop = project.properties["myPropName"] ?: "myDefaultValue"

val prop = project.properties["myPropName"] ?: error("Property not found")

if (project.hasProperty("special")) {
    val prop = project.properties["myPropName"]
}

Note that you can omit the project. prefix as it is implicit in Gradle build files.