Mostly lazy data generators for property based testing using the Spock test framework

Providing test data, especially when attempting to test for a wide range of inputs is tedious if not impossible to do by hand. Generating inputs allows for more thorough testing without a dramatic increase in effort. In Spock [data driven tests] (http://spock-framework.readthedocs.org/en/latest/data_driven_testing.html#data-pipes) can have data provided by any Iterator. Spock Genesis provides a variety of classes that extend from Generator which meet that interface. Where possible the generators are lazy and infinite.

From gradle:

repositories {
    jcenter()
}

dependencies {
    testCompile 'com.nagternal:spock-genesis:0.6.0'
}

The primary way of constructing generators is spock.genesis.Gen which provides static factory methods for data generators.

@Unroll
def 'test reverse #string'() {
    when:
        def reversed = string.reverse()

    then:
        reversed.size() == string.size()
        if (string) {
            string.eachWithIndex { letter, i ->
                letter == reversed[-(i + 1)]
            }
        }
        reversed.reverse() == string

    where:
        string << Gen.these('', 'foo').then(Gen.string).take(10000)
}

Given a Person class create a generator that can supply instances:

    Gen.type(Person,
        id: Gen.integer(200..10000),
        name: Gen.string(~/[A-Z][a-z]+( [A-Z][a-z]+)?/),
        birthDate: Gen.date(Date.parse('MM/dd/yyyy','01/01/1940'), new Date()),
        title: Gen.these('', null).then(Gen.any('Dr.', 'Mr.', 'Ms.', 'Mrs.')),
        gender: Gen.character('MFTU'))

Check Spock-Genesis documentation is here or see SamplesSpec for more examples

• Update dependencies

• Add support for using regular expressions for String generation. Thanks to Generex
• Using Groovy constructor selection for single arg Pojo construction

• improve toGenerator extension methods
• better error handling for POJO construction
• isFinite method to determine if generator will terminate

• switch to Iterable from Iterator
• improve performance of long generation using min and/or max
• improved documentation (thanks to @mariogarcia)
• @Iterations annotation
• updated dependencies
• ability to set the seed of random generators

• permute to generate combinations from composite generators

The only prerequisite is that you have JDK 7 or higher installed.

After cloning the project, type ./gradlew clean build (Windows: gradlew clean build). All build dependencies, including Gradle itself, will be downloaded automatically (unless already present).

• Spock Homepage -- http://spockframework.org
• GitHub -- https://github.com/Bijnagte/spock-genesis
• Generex -- https://github.com/mifmif/Generex