shift-left

The Behavior-Driven Three Amigos

Recently, my manager said to me, “Andy, your BDD documentation looks great, but could you please mention The Three Amigos?” A brief flash of panic came over me – I had never heard of “The Three Amigos” before. My immediate thought was the 1986 film of the same name or the Disney film The Three Caballeros. After a little research, I knew exactly who they were; I just didn’t know they had a name.

Who are “The Three Amigos”?

The Three Amigos” refers to a meeting of the minds of the three primary roles involved in producing software:

  1. Business – Often named the “business analyst” (BA) or “product owner” (PO), the business role provides what problem must be solved. They provide requirements for the solution. Typically, the business role is non-technical.
  2. Development – The developer role provides how the solution to the problem will be implemented. They build the software and must be very technical.
  3. Testing – The testing role, sometimes named “quality assurance” (QA), verifies that the delivered software product works correctly. They also try to find defects. The tester role must be somewhat technical.

During software development, The Three Amigos should meet regularly to discuss how the product will be developed. It is a shift left practice to avoid misunderstandings (like a game of telephone), thus improving quality and avoiding missed deadlines. The discussions should include only the individuals who will actually work on the specific deliverable, not the whole team.

While The Three Amigos seems most popular in Agile, it can be applied to any software development process. Some (here and here) advocate regularly scheduled formal meetings. Others (here and here) interpret it as an attitude instead of a process, in which the roles continuously collaborate. Regardless of implementation, The Three Amigos need to touch base before development begins.

Applying BDD

The Three Amigos fits perfectly into behavior-driven development, especially as part of BDD with Agile. Behavior scenarios are meant to foster collaboration between technical and non-technical roles because they are simple, high-level, and written in plain language. Given-When-Then provides a common format for discussion.

Ideally, when The Three Amigos meet during grooming and planning, they would formalize acceptance criteria as Gherkin features. Those feature files are then used directly by the developer for direction and the tester for automation. They act like a receipt of purchase for the business role – the feature file says, “This is what you ordered.”

Since BDD relies on feature files as artifacts, The Behavior-Driven Three Amigos must be more than just an attitude. The point of the collaboration is to produce feature files early for process efficiency. Less formal meetings could quickly devolve into all-talk-no-action.

Don’t Presume Anything

Don’t presume that the three roles will naturally collaborate on their own. I’ve seen teams in which the testers don’t participate in planning. I’ve also seen organizations in which automation engineers don’t help to write the test cases that they need to automate! Developers often abdicate responsibility for testing considerations, because “that’s QA’s job.” And, specifically for BDD, I’ve noticed that product owners resist writing acceptance criteria in Gherkin because they think it is too technical and beyond their role.

The Three Amigos exists as a named practice because collaboration between roles does not always happen. It is an accountability measure. Remember, the ultimate purpose for The Three Amigos is higher quality in both the product and the process. Nobody wants more meetings on their calendar, but everyone can agree that quality is necessary.

BDD 101: Introducing BDD

Series Overview

BDD 101 is a blog series to teach the basics of behavior-driven development. It is both a “getting started” guide for BDD beginners, as well as a best-practice reference for pros. I wrote this series for anyone involved in the daily duties of software development: developers, testers, scrum masters, product owners, and managers. The content in this series comes from my experiences using BDD for many projects. It focuses on Gherkin-based specification, and test automation will be a major theme. If this series is for you, then let’s dive in!

The BDD 101 table of contents is given on the Automation Panda BDD page. Note that some articles in the series were posted months apart and will not all appear together using the “previous” and “next” article arrows.

The Big BDD Picture: The main goals of BDD are collaboration and automation.

What is a Behavior?

behavior is how a product or feature operates. It is defined as a scenario of inputs, actions, and outcomes. A product or feature exhibits countless behaviors. Identifying behaviors individually brings clarity and simplicity. It also helps explain how behaviors are related. Below are examples of behaviors:

  • Logging into a web page
  • Clicking links on a navigation bar
  • Submitting forms
  • Making successful service calls
  • Receiving expected errors

Separating individual behaviors makes it easy to define a system without unnecessary repetition. For example, there may be multiple ways to navigate to the same page.

Nav Behaviors

Search from a text field and searching directly from URL parameters both lead to the same results page.

What is BDD?

Behavior­-Driven Development (BDD) is a test­-centric software development process that grew out of Test-­Driven Development (TDD). It has been around since roughly the mid-2000s. BDD focuses on clearly identifying the desired behavior of a feature from the very start. Behaviors are identified using specification by example: behavior specs are written to illustrate the desired behavior with realistic examples, rather than being written with abstract, generic jargon. They serve as both the product’s requirements/acceptance criteria (before development) and its test cases (after development). Gherkin is one of the most popular languages for writing formal behavior specifications – it captures behaviors as “Given-When-Then” scenarios. With the help of automation tools, scenarios can easily be turned into automated test cases. Anybody from engineers to product owners can write BDD scenarios, since they are just English phrases. BDD keeps developers focused on delivering precisely what the product owner wants. It also expedites testing. As such, BDD pairs nicely with Agile Software Development.

Quick Points

  • BDD is specification by example.
    • When someone says “BDD”, immediately think of “Given-When-Then”.
  • BDD focuses on behavior first.
    • Behavior scenarios are the cornerstone of BDD.
  • BDD is a refinement of the Agile process, not an overhaul.
    • It formalizes acceptance criteria and test coverage.
  • BDD is a paradigm shift.
    • Behaviors become the team’s main focus.

The Origins of BDD

The following quote comes from an article entitled Introducing BDD, written by Dan North (the “Father of BDD”) in March 2006:

I had a problem. While using and teaching agile practices like test-driven development (TDD) on projects in different environments, I kept coming across the same confusion and misunderstandings. Programmers wanted to know where to start, what to test and what not to test, how much to test in one go, what to call their tests, and how to understand why a test fails.

The deeper I got into TDD, the more I felt that my own journey had been less of a wax-on, wax-off process of gradual mastery than a series of blind alleys. I remember thinking “If only someone had told me that!” far more often than I thought “Wow, a door has opened.” I decided it must be possible to present TDD in a way that gets straight to the good stuff and avoids all the pitfalls.

My response is behaviour-driven development (BDD). It has evolved out of established agile practices and is designed to make them more accessible and effective for teams new to agile software delivery. Over time, BDD has grown to encompass the wider picture of agile analysis and automated acceptance testing.

12 Awesome Benefits

BDD improves the development process in a dozen ways:

Inclusion Anyone can write BDD scenarios, because they are written in plain English. Think of The Three Amigos.
Clarity Scenarios focus specifically on the expected behavior of the product under development, resulting in less ambiguity for what to develop.
Streamlining Requirements = acceptance criteria = test cases. Modular syntax expedites automation as well.
Shift-Left Test case definition inherently becomes part of grooming.
Artifacts Scenarios form a collection of test cases. Any tests not automated can be added to a known automation backlog.
Automation BDD frameworks make it easy to turn scenarios into automated tests.
Test­-Driven Most BDD frameworks can run scenarios to fail until the feature is implemented.
Code Reuse “Given-When­-Then” steps can be reused between scenarios.
Parameterization Steps can be parameterized. For example, a step to click a button can take in its ID.
Variation Using parameters, example tables make it easy to run the same scenario with different combinations of inputs.
Momentum Scenarios become easier and faster to write and automate as more step definitions are added.
Adaptability Scenarios are easy to rewrite as the products and features change.

Testing Recommendations

Since BDD focuses on actual feature behavior, behavior specs are best for higher-level, functional, black box tests. For example, BDD is great for testing APIs and web UIs. Gherkin excels for acceptance testing. However, behavior specs would be overkill for unit tests, and it is also not a good choice for performance tests that focus on metrics and not pass/fail results. Read more about this in the article BDD 101: Unit, Integration, and End-to-End Tests.

Next Steps

Lost yet? Don’t worry – this first post presented a lot of information. Things will make much more sense after learning how to write Gherkin test scenarios, which will be covered in the next post in this 101 series.