Esta sesión está constituida por dos partes: en la primera explicaré en qué consiste el test driven development y cómo funciona a grandes rasgos; posteriormente mostraré ejemplos de cómo se puede implementar en el lenguaje de programación Go utilizando el framework Ginkgo y la biblioteca de afirmaciones Gomega.

1. TDD in Go with Ginkgo and
Gomega
Presenta:
Eddy Reyes

2. Eddy Reyes
Founder of Mindsight
● AI for Software Project Management
● Tells you when tasks will be finished by watching code changes.

3. Test Driven Development
● Write the test
● Watch it fail
● Implement new code
● Test passes
I CAN HAZ
DESIGN??

4. Anatomy of a Test
● GIVEN: X is true
● WHEN: Y happens
● THEN: Z must be true

5. TDD What’s it Good For?
● Helps you create unit tests
● Tests are enforceable design spec
● Forces deep understanding of design before coding

6. TDD, Ain't Nobody Got Time For That
● TDD takes up front additional effort
● Tests are hard- code that reasons about the behavior of code
● Design must be understood before test is written

7. TDD Pro Tips
● Divide and Conquer! Work with the smallest piece possible
● Experiment, prototype, learn your design
● Throw away your prototype! Start fresh with tests first

8. Go testing Package
In a file named XX_test.go:
func TestMyThing(t *testing.T) {
result, err := DoMyThing()
if err == nil {
t.Error(“Failed with error:”, err)
}
if !result {
t.Error(“Expected true”)
}
}

9. Go Testing Capabilities (Batteries Included)
Run your tests:
$ go test -race
… Also tells you if a race condition is detected in your code
Compute test coverage:
$ go test -coverprofile=coverage.out
$ go tool cover -html=coverage.out

10. Alternative Testing Tools
Ginkgo / Gomega
● Jasmine clone for Go
● Ginkgo- BDD-style test specification
● Gomega- Assertion syntax
Convey
● https://github.com/smartystreets/goconvey

11. Example With Ginkgo / Gomega

12. Ginkgo Contexts

13. Tests with Channels + Concurrency

14. Mocking
net/http/httptest
● Create mock HTTP servers or clients
● Mock out HTTP interactions (simulate server responses, client responses)

15. Mocking
What about when you have a non-HTTP external component?
Use Interfaces!!
Here we never use
the mongo library
directly in code:

16. Mocking
To test code interacting with the DB:
● Create mock implementation of DBConnection
● Pass the mock into your code from the test

17. Eddy Reyes
@0x000edd1e
@Mindsight_Tech
linkedin.com/in/ereyes01
eddy@mindsight.io
www.mindsight.io
elr715