BDD with Cucumber

Behavior-Driven Development (BDD) helps teams write human-readable descriptions of software behavior in a structured format. Vyndara uses this development format to guarantee every logic can be understood easily and is covered by verifiable test cases.

In Go, we use Godog, a Cucumber implementation, to execute these specifications.

This guide introduces BDD with Godog and provides a structured test setup.

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Getting Started

Ensure you have the Arematics testing library go-tests installed:

go install github.com/Arematics/go-tests

Then, write your feature files inside a features/ directory using Gherkin syntax.

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Test Initialization

We use a helper function to initialize our Godog tests:

func InitializeTests(t *testing.T, initializer func(ctx *godog.ScenarioContext), featurePath string, suiteName string) {
    Test = t
    options := &godog.Options{
        Format: "pretty",                  
        Output: colors.Colored(os.Stdout), 
        Paths:  []string{featurePath},    
    }

    suite := godog.TestSuite{
        Name:                suiteName,
        ScenarioInitializer: initializer, 
        Options:             options,
    }

    if status := suite.Run(); status != 0 {
        t.Fail()
    }
}

This function runs a Godog test suite based on the provided feature path and scenario initializer.

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Defining Common Steps

Godog binds test scenarios to step definitions. For example you can write Scenario definitions like that:

func initCommonServiceTests(ctx *godog.ScenarioContext) {
    Init(context.Background()) // Initialize environment in go-orm

    ctx.Step(`^a database is available$`, aDatabaseIs)
    ctx.Step(`^I create an entity with test value "([^"]*)"$`, canCreateValue)
    ctx.Step(`^I should be able to retrieve an entity with value "([^"]*)"$`, canReadItAndHaveValue)
    ctx.Step(`^I can update the entity to have the value "([^"]*)"$`, canUpdateItWithValue)
    ctx.Step(`^I can delete the entity$`, canDeleteIt)
    ctx.Step(`^it’s no longer available$`, isDeleted)
}

These steps map Gherkin statements to Go functions.

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Running Feature Tests

We call InitializeTests from the go-tests library for each feature file:

func TestServiceFeatures(t *testing.T) {
    tests.InitializeTests(
        t,
        initCommonServiceTests,
        "./features/basic_service_operations.feature",
        "Basic Service Operations",
    )
}

This ensures multiple test suites can run independently.

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Running the Tests

Execute the tests using:

go test -v ./...

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Conclusion

With BDD using Godog, tests remain understandable for both developers and non-technical stakeholders. This structured approach ensures feature validation in a human-readable format while integrating seamlessly with Go.