Yearly Archives: 2014

/2014

Do you practice BDSA?

I get to visit a lot of teams. I talk to my peers about their experiences too. For every agile success story there seem to be a load of less happy outcomes.

There are three common ways that I’ve seen agile ‘adoption’ go wrong, and they are:

Bondage – “You can never change the business. That’s just the way things work here.”
Domination – “That estimate is too big – make it smaller. These tasks are assigned to you.”
Sadism – “Work longer hours. Honour your commitments. Of course you will work on multiple projects”

If these sound familiar, then maybe your organisation uses BDSA – Bondage, domination and sado-agile.

By |December 18th, 2014|Agile, Musings, Practices|0 Comments

Half a glass

Is this glass half empty or half full?

There’s normally more than one way to interpret a situation, but we often forget that the situation itself may be under our control.

I often find my clients have backed themselves into a corner by accepting an overly restrictive understanding of what they’re trying to achieve. They will tell me, for example, that this story is too big BUT that it can’t be split, because then it wouldn’t deliver value. Or, they might be saying that there’s no point writing unit tests BECAUSE the architecture doesn’t support it. Or even, it’s not worth fixing this flickering test, because it ALWAYS works when they run it locally.

I encourage them to rethink the situation. A slice through that story may not deliver the final solution the customer needs, but it will act as a small increment towards the solution. Minor refactorings are usually enough to make a section of the code independently testable. That flickering test is undermining any confidence there might be in the test suite – fix it or delete it.

Don’t try to put a spin on a half-full glass – rethink the glass.

Instead of asking if the glass is half-full or half-empty, use half a glass.

(It turns out that wittier minds than mine have already applied themselves to this proverb – here’s a bumper collection.)

By |December 15th, 2014|Agile, Musings, Practices|0 Comments

Diamond recycling (and painting yourself into a corner)

The post I wrote recently on recycling tests in TDD got quite a few responses. I’m going to take this opportunity to respond to some of the points that got raised.
Do we really need to use the term “recycling”?
The TDD cycle as popularly taught includes the instruction to “write a failing test”. The point of my article was to observe that there are two ways to do that:

write a new test that fails
change an existing, passing test to make it fail

It’s this second approach that I’m calling “recycling”. Alistair Cockburn says that “it’s a mystery this should need a name” and it probably doesn’t. However, I’ve regularly seen novice TDD-ers get into a mess when making the current test pass causes other test(s) to fail. Their safety net is compromised and they have a few options, none of which seem very appealing:

Roll back to last green
Comment out the failing test(s)
Modify the failing test(s) to make them pass again

Whichever way you go to get out, you’ll want to try to avoid painting yourself into a similar corner in future.
Why do tests that used to pass start failing?
Ron Jeffries suggests that this will only happen if the tests don’t “say something universally true about the problem and solution.” Several people (including George Dinwiddie and Sandro Mancuso) demonstrated that this problem can be solved by writing a series of tests that each say something “universally true.” However, to me, this seems like a similar approach to that recommended by Alistair Cockburn in his “Thinking Before Programming” post.

I’m a big fan of thinking before programming. In the courses that I deliver, I routinely prevent students from touching the keyboard until they’ve thought their way around the problem. But, it’s just not realistic to expect that […]

By |December 9th, 2014|Agile, BDD, Cyber-Dojo, TDD, Uncategorized|3 Comments

Recycling tests in TDD

The standard way that TDD is described is as Red-Green-Refactor:

Red: write a failing test
Green: get it to pass as quickly as possible
Refactor: improve the design, using the tests as a safety net
Repeat

TL;DR; I’ve found that step 1) might be better expressed as:

Red: write a failing test, or make an existing test fail

Print Diamond
One of the katas that I use in my TDD training is “Print Diamond”. The problem statement is quite simple:
Given a letter, print a diamond starting with ‘A’ with the supplied letter at the widest point.

For example: print-diamond ‘C’ prints

  A
 B B
C   C
 B B
  A
I’ve used Cyber-Dojo to demonstrate two different approaches so you can follow along with my example, but I recommend you try this kata on your own before reading further. .
Gorilla
The usual approach is to start with a test for the simple case where the diamond consists of just a single ‘A’:
> PrintDiamond(‘A’) 

A
The next test is usually for a proper diamond consisting of ‘A’ and ‘B’:
> PrintDiamond(‘B’)

 A
B B
 A
It’s easy enough to get this to pass by hardcoding the result. Then we move on to the letter ‘C’:
> PrintDiamond(‘C’)

  A
 B B
C   C
 B B
  A
 

The code is now screaming for us to refactor it, but to keep all the tests passing most people try to solve the entire problem at once. That’s hard, because we’ll need to cope with multiple lines, varying indentation, and repeated characters with a varying number of spaces between them.
Moose
The approach that I’ve been playing with is to start as usual, with the simplest case:
> PrintDiamond(‘A’) 

A
 

For the second test, however, we start by decomposing the diamond problem into […]

By |November 23rd, 2014|BDD, Cyber-Dojo, Practices, TDD|12 Comments

User Story Mapping

I’ve been reading Jeff Patton’s work online for years, learning from his ideas and approaches. You’ve probably come across his Mona Lisa analogy for iterative and incremental development – and if you haven’t this is a good time to go and read it 😉

Well, he has just released a book, User Story Mapping, and it is every bit as good as I would have hoped. If you don’t know what User Story Mapping is then this book will (obviously) tell you, but you will learn a whole lot more than that. I believe that this is THE missing agile book.

Throughout the book Jeff uses examples from his clients to demonstrate the simple techniques that he uses. ANd the most important ingredient, for me, is the emphasis on the need for rapid feedback and the need to SLICE USER STORIES THINLY. He’s not alone in this regard – JB Rainsberger calls it “Product Sashimi” and Alistair Cockburn calls is “Elephant Carpaccio”.

Go buy this book today. Don’t let it languish on your bookshelf – read it. And start putting the advice into practice as soon as you can.

By |November 17th, 2014|Agile, Practices|1 Comment

Using SpecFlow on Mono from the command line

SpecFlow is the open source port of Cucumber for folk developing under .NET. It has been compatible with Mono (the open source, cross platform implementation of the .NET framework) for several years, but most of the documentation talks about using it from within the MonoDevelop IDE. I wanted to offer SpecFlow as one of the options in Cyber-Dojo and, since the Cyber-Dojo IDE is your browser, I was looking for a way to make it all happen from the command line.

Cyber-Dojo already offers C#/NUnit as an option, so I used this as my starting point for making SpecFlow available. I came up with a list of tasks:

Install SpecFlow
Generate ‘code-behind’ each feature file
Include generated code in compilation

Install SpecFlow
I found an interesting website that had detailed instructions for installing SpecFlow on Mono. There don’t seem to be any handy ‘apt-get’ packages, so it is basically a process of downloading the binaries and installing them in the GAC, for example:

  gacutil -i TechTalk.SpecFlow.dll
Generate ‘code-behind’ each feature file
SpecFlow ships with a command line utility, specflow.exe. I tried following the instructions from the article that had helped me with the installation, but they didn’t work for me. I ended up invoking the utility directly:

  mono ./specflow.exe

Running specflow.exe like this lists the operations that the utility provides, from which I chose ‘generateall’, because (according to the documentation) it should do exactly what I want:
re-generate all outdated unit test classes based on the feature file.
Unfortunately it needs a Visual Studio project file (csproj) as input, and since we’re not using Visual Studio we don’t have one. This led me to insert a fourth item in my task list: “Create csproj file”
Create csproj file
I started with an MSDN article that describes creating a minimal […]

By |October 5th, 2014|BDD, Cyber-Dojo, Practices, TDD, Unit testing|1 Comment

To TDD or not to TDD? That is not the question.

Over the past few days a TDD debate has been raging (again) in the blog-o-sphere and on Twitter. A lot of big names have been making bold statements and setting out arguments, of both the carefully constructed and the rhetorically inflammatory variety. I’m not going to revisit those arguments – go read the relevant posts, which I have collected in a handy timeline at the end of this post.
Everyone is right
Instead of joining in the argument, I want to consider a conciliatory post by Cory House entitled “The TDD Divide: Everyone is right.” He proposes an explanation for these diametrically opposed views, based upon where you are in the software development eco-system:
Software “coaches” like Uncle Bob believe strongly in TDD and software craftsmanship because that’s their business. Software salespeople like Joel Spolsky, Jeff Atwood, and DHH believe in pragmatism and “good enough” because their goal isn’t perfection. It’s profit.
This is a helpful observation to make. We work in different contexts and these affect our behaviour and colour our perceptions. But I don’t believe this is the root cause of the disagreement. So what is?
How skilled are you?
In Japanese martial arts they follow an age old tradition known as Shu Ha Ri, which is a concept that describes the stages of learning to mastery. This roughly translates as “first learn, then detach, and finally transcend.” (I don’t want to overload you with Japanese philosophy, but if you are interested, please take a look at Endo Shihan’s short explanation)

This approach has been confirmed, and expanded on, in modern times by research conducted by Stuart and Hubert Dreyfus, which led to a paper published in 1980. There’s a lot of detail in their paper, but this diagram shows the main thrust […]

By |May 2nd, 2014|Agile, TDD, Unit testing|3 Comments

The most important change you can make to help your team succeed

How busy are you?
Are you close to a deadline? Is the team feeling pressure? Every team I visit seems to be under the same heavy workload, and consequently has a lot of improvements to the process, the environment, the technology that they can’t quite get to yet. They know they need to get to them, and they will…. when they have time.

But they won’t get time.

Ever.

TL;DR: Build slack into your iteration

The nature of time
When I started trying to write a book I spoke to a colleague, Jon Jagger. I whined that I just didn’t seem to be finding the time and he replied with wise words: “You won’t find the time. You’ve got to make the time.”

The same is true for any tasks that support the development team that don’t obviously deliver immediate working software for the customer. The reasons for this are many, but the root cause is normally disempowered teams. Teams who ask their product owner to prioritise tasks that the product owner has no way of prioritising appropriately. Most POs should not be asked to choose between a user story that delivers a feature they understand and a technical task that they don’t. It’s a no-brainer – they’ll always choose the user story to maximise customer value. Even if the technical task will actually deliver greater customer value.

Before I continue, I’d like to remind you of two things: sustainable pace and commitment
Sustainable pace
The agile manifesto is quite restrained in its pronouncements. One of the 12 principles it states is this: “Agile processes promote sustainable development. The sponsors, developers, and users should be able to maintain a constant pace indefinitely.” This doesn’t mean we don’t work hard. It doesn’t mean we never come in early, work […]

By |April 30th, 2014|Agile, Practices|2 Comments

5 rules of continuous delivery

Inspired by Sandi Metz’s BaRuCo 2013 presentation “Rules” (which you should watch if you haven’t yet) I started thinking about whether there were some  rules that might be useful in the continuous delivery domain to “screen for cooperative types”.

I came up with these as a starting point:

Check in everything – we’re used to putting source code in version control, but we’re often less good at configuration management. Do you control your test data? Your database scripts? Your operating system patch level? If not how can you be sure that the environment you provision tomorrow will be identical to the one you provisioned last week?
Automate everything – “to err is human”, as the saying goes. Any manual process is susceptible to failures, so get rid of as many as you can. Some continuous delivery pipelines still have manual approval steps in them as part of the process, but the presence of the human is not functionally essential.
Continuous != occasionally – the more we do something, the easier it gets. One of the reasons to do something continuously is to decrease the cost and remove the fear. If it “costs too much” to deploy often, then work on reducing the cost not reducing the frequency.
Collaborate – people are not plug compatible. To get the most from the different people in the organisation we need to work together. For me, this was one of the major “innovations” of devops – no more ‘us’ and ‘them’, just ‘we’.
One step at a time – it’s hard to do everything all at once, which is why we iterate in software development. Continuous delivery is no different – don’t expect everything to “just happen”.

Do these make sense to you? What essential ingredients have […]

By |February 28th, 2014|Agile, Continuous Delivery, Practices|3 Comments

Continuous delivery – the novel

I find myself recommending the same books over and over again. When speaking to techies I invariably recommend GOOS; when speaking to managers The Mythical Man Month or Waltzing With Bears. Over the past year or two, I’ve also pointed a lot of organisations at Continuous Delivery by Jez Humble and Dave Farley. It’s an important book, but I think it could have been shorter, and that’s an important consideration for the target audience. If you consider the other books I recommend that weigh in at 384, 336 and 196 pages respectively, Continuous Delivery extends to 512 and it feels longer. That’s not because it isn’t good – it is – but because it is detailed and quite dense.

Last week I finally heeded Liz Keogh’s advice and read The Phoenix Project (“a novel about IT, Devops and helping your business win”). In terms of prose style, it doesn’t compete with Liz’s own efforts, but it is very readable and does a great job of getting some quite tricky concepts across (Lean, Theory of Constraints, The Three Ways). The authors acknowledge their debt to Goldratt’s The Goal, and indeed they are ploughing the same furrow, but in the field of software. Amazon says the print copy is 343 pages long, but I read it on the Kindle and it felt shorter than that.

The reason I’m adding this book to my recommended list isn’t just because it’s short and readable. It’s because it makes some very frightening concepts very easy to digest. I didn’t know how to explain quite why I liked it so much until I found myself reading a Venkat Rao post this morning, where he describes how we change our minds:

You have to:

1. Learn new […]

By |February 24th, 2014|Agile, Practices, Systems|1 Comment