An implementation of Cucumber BDD-style testing for Go.

$ go get github.com/gucumber/gucumber/cmd/gucumber

Cucumber tests are made up of plain text ".feature" files and program source "step definitions", which for Gucumber are written in Go.

Put feature files internal/features/ with whatever organization you prefer. For example, you might create internal/features/accounts/login.feature with the following text:

@login
Feature: Login Support

  Scenario: User successfully logs in
    Given I have user/pass "foo" / "bar"
    And they log into the website with user "foo" and password "bar"
    Then the user should be successfully logged in

Create step definitions to match each step in your feature files. These go in ".go" files in the same internal/features/ directory. We might create internal/features/accounts/step_definitions.go:

package accounts

import (
	. "github.com/gucumber/gucumber"
)

func init() {
	user, pass := "", ""

	Before("@login", func() {
		// runs before every feature or scenario tagged with @login
		generatePassword()
	})

	Given(`^I have user/pass "(.+?)" / "(.+?)"$`, func(u, p string) {
		user, pass = u, p
	})

	// ...

	Then(`^the user should be successfully logged in$`, func() {
		if !userIsLoggedIn() {
			T.Errorf("user should have been logged in")
		}
	})
}

The T value is a testing.T style value that represents the test context for each test. It mostly supports Errorf(fmt, args...), but also supports other convenience methods. See the API documentation for more information.

To run your tests, execute:

$ gucumber

You can also specify the path to features in command line arguments:

$ gucumber path/to/features

You can also filter features and scenarios by tags:

$ gucumber -tags=@login # only run login feature(s)

Or:

$ gucumber -tags=~@slow # ignore all "slow" scenarios

This library was written by Loren Segal in 2015. It is licensed for use under the MIT license.