bdd

Overview ¶

Package bdd provides a Behavior-Driven Development (BDD) style testing framework.

It offers a domain-specific language (DSL) that is close to natural language, making test structures highly readable and expressive. The framework is built on Go's standard `testing` package and integrates seamlessly with `testing.T`.

Key Concepts ¶

The BDD framework is structured around three main keywords:

• Given: Sets up the initial state or preconditions for the test.
• When: Defines the action, event, or behavior being tested.
• Then: Asserts the expected outcomes using various Checkers.

Usage Example ¶

You can start a BDD test by wrapping a standard `*testing.T` using `bdd.From(t)`.

func TestCalculator(t *testing.T) {
	bdd.From(t).
		Given("initial value is 1", func(t bdd.T) {
			v := 1

			t.When("we add 1", func(t bdd.T) {
				v += 1
				t.Then("it should equal 2", bdd.Equal(2, v))
			})

			t.When("we add 2", func(t bdd.T) {
				v += 2
				t.Then("it should equal 3", bdd.Equal(3, v))
				t.Then("it should not equal 4", bdd.NotEqual(4, v))
			})
		})
}

Alternatively, you can use the `bdd.Given` helper to create a test function directly:

func TestStringConversion(t *testing.T) {
	v := 0
	bdd.Given(func(t bdd.T) {
		v = 1
		t.Then(
			"the string representation should be '1'",
			bdd.Equal("1", strconv.Itoa(v)),
		)
	})(t)
}

Checkers ¶

The `Then` step uses `Checker` interfaces to perform assertions. This package provides a wide range of built-in checkers (e.g., `Equal`, `BeNil`, `BeTrue`, `HaveLen`, `IsError`, etc.) which are wrappers around the matchers from the `github.com/xoctopus/x/testx` package.