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The Big Picture

December 27th, 2007 Comments off

Christmas for me is celebration, gormandizing and the joy of happy children. It’s also a time for rest and reflection, and when I think back on this year there is one thing that disturbs me: for me this was a year of us and them.

The company I work for is divided; we have three divisions divided into several so called “functions”, which in turn is divided into teams, where people mostly work – well – alone… And on top of that we have several temporary project organizations fighting for the scarce resources.

Although we’re trying to change things for the better, there is still a lot of distrust and arrogance that stems from lack of understanding between the various formations. We are an organisation that needs more empathy.

My guess is that this is a common problem in our business. We tend to mentally separate us from the others, thinking in terms of us and them. There’s a lot of “those stupid users”, and “management has no clue” kind of talk out there.

We even turn on ourselves. What’s the first thing you do when you look at code that is new to you? I know my reflex is to try and spot design flaws, so that I can point them out. If I can’t understand the code fast enough, the normal response is “who created this piece of crap?”

These responses only show a lack of empathy in the person that utters them. Nowadays I try not to be so judgemental when I look at code that others have created. I’ve come to realize that while there is always a reason for crappy code, it’s never because the programmer wanted to do a bad job. He or she has most likely tried their best, with their current knowledge, or made a deliberate choice, given the circumstances. At least they deserve respect for that.

When we start talking negatively about each other, in terms of us and them, it might be because we lost track of the bigger picture. Here’s an exercise that helps me when I need to put things into perspective. Look at this image from Big Sky Astronomy Club.

Pale Blue Dot

The image was taken by Voyager 1 in 1990 on its way out of the solar system. The little blue dot is planet earth. Fellows, that pixel is our home!

In this humbling perspective there is no us and them; There’s only us.

Cheers!

Categories: software development Tags:

Don’t unit-test GUI

December 20th, 2007 21 comments

I’m currently rereading parts of the book Test-Driven Development: A Practical Guide, by David Astels. It’s a great book in many ways, well worth reading, but I have objections to one particular section in the book.
The author tries to convince me that developing my user interfaces using a test-driven approach is a good thing to do. I disagree.

I love TDD, it’s one of the most powerful development techniques I know, but it’s not without limitations. For one thing, code with unit-tests attached is more difficult to change. This is often an acceptable price to pay since the benefit of producing and having the unit-tests is usually greater.

But the return of the investment isn’t always bigger than the price, and sometimes the cost of change exceeds the benefit of protection. That’s why most developers won’t use TDD for experimental code, and that’s why I’m not using it to test my user interfaces.

I prefer to develop GUIs in a RAD environment, visually dragging and dropping components, moving them around, exchanging them for others if better ones are to be found. In that process unit-testing just gets in my way. After all, the GUI is supposed to be a thin layer, without business logic, so there is only so much to test.

One could theoretically test that the form contains certain key components, that they are visible, have a certain position or layout, stuff like that – but I find that kind of testing too specific for my taste.

In my opinion, unit-testing should test functionality, not usability. It shouldn’t dictate whether I decide to show a set of items in a plain list or in a combo-box. What it should do, is test that the business logic of my code produce the correct set of items, and leave the graphical worries to the testers.

This brings us to something that is sometimes misunderstood: Unit-testing can never replace conventional testing. Some things are just better left to humans. Like testing user interfaces.

Cheers!

Does unit-testing deserve its own DSL?

December 10th, 2007 7 comments

We’ve done a lot with testing frameworks over the years, but does the testing concern deserve its own standalone DSL?

This intriguing question was asked by Michael Feathers in his Mock Objects: Leaping out of the Language post. My spontaneous answer is: Absolutely!

I’m a big fan of xUnit frameworks, but when I imagine an alternative unit-testing specific language one special property comes to mind, a feature that would really make a difference. I’d call it unconditional mocking. With a DSL based unit-testing framework one could test really complex objects, even legacy code, since mocking internal objects would require no change to the original programming interface.

For example, this (nonsense) code

class A {
  private B _b;

  // constructor
  this A() {
    _b = new B()
  }
}

unittest {
  // B can not be mocked
  A a = new A();
}

would require refactoring in order for _b to be mockable.

class A {
  private B _b;

  // constructor
  this A(B b) {
    _b = b;
  }
}

unittest {
  // B could be mocked
  B b = new BMock(...);
  A a = new A(b);
}

But in a unit-testing DSL, one should be able to mock any object, in this case B, without changing the source code first. This is handy for dealing with the unit-testing paradox: Refactoring requires a unit-testing harness to make sure no functionality gets broken, but unit-testing requires testable code; So what to do when the code isn’t testable? A unit-testing DSL would make it easier to put up the initial testing harness.

Also, as Michael points out, a unit-testing DSL could be used to mock any kind of construction, not just objects: Functions and methods for instance. Oh man, could I have use for such a feature?

To give us an image of a DSL for unit-testing in a non-object-oriented language like C, Michael provides this example:

function send_port_command with 90, “CMD: 12”
            calls io_mode which returns M_READ
            calls set_mode with M_WRITE
            calls write_byte with 90
            calls write_bytes with “12”
            returns E_OKAY

That would be testing a function like this:

status send_port_command(byte port, const char *message)
{
  if(io_mode() == M_READ)
    set_mode(M_WRITE);
  write_byte(port)
  write_bytes(translate_command(message));
  return E_OKAY;
}

I have a problem with his example though. In my opinion the test-code resembles the target code a little too much, like a bad manager performing low-level supervision. Too detailed testing beats the purpose since it makes changes more difficult. My philosophy is that test-code should test WHAT the code does, and not bother too much on the HOW.

So, my not so thought through proposal, using Michaels example, would be something like this:

TEST send_port_command

MOCK write_byte(port)
EXPECT port == 90

MOCK write_bytes(bytes)
EXPECT bytes == "12"

CALL send_port_command with 90, "CMD: 12"
EXPECT E_OKAY

Of course there should be support for more advanced mock features like call counting:

MOCK  write_bytes(bytes)
EXPECT   "12", "13"

CALL send_port_command with 90, "CMD: 12"
EXPECT E_OKAY
CALL send_port_command with 90, "CMD: 13"
EXPECT E_OKAY

or

MOCK  write_bytes(bytes)
EXPECT  2 CALLS

or sequential values

MOCK  io_mode
RETURN  M_READ, M_WRITE

Implementing the DSL would be a hefty task though. But, the problems aside, how would your unit-testing DSL be like? I’d be very interested to hear your opinions.

Cheers!

Categories: DSLs, programming, testing Tags:

Tools of The Effective Developer: Touch Typing

December 6th, 2007 1 comment

A colleague of mine thinks learning touch typing is a waste of time. He even suggests that it might be a disadvantage for a programmer to be able to type fast. While typing slowly, he reasons, one has time to reflect upon the work at hand. Well, I don’t share his point of view. I mean, should a cook not become skilled with his knives because slicing and chopping slowly gives more time to plan the next step? Of course not!

As a programmer, typing is what you do most, so you should spend time to become good at it. Touch typing is not only about rapid typing. It’s also about the freedom of your eyes. You can look at the screen and still be able to strike the right keys. That way you’ll discover typing errors more quickly.

Being able to look away and still type has another great advantage. When I get into “the zone”, my most productive state, I’d like to stay there as long as possible without interruption. If someone comes by I’m still able to continue my work thanks to touch typing. All I have to do is turn my face to the intruder and fake interest with nodding, humming and carefully placed responses like “mmm’right”, “mmm’kay” or “mmm’yes”. Try it, and I promise your productivity will skyrocket. 🙂

Learning touch typing has been well worth the investment for me. It took me approximately two months to become fluent, spending 20-60 minutes of practice every day. To my help I had Stamina, a free typing tutor software, which I gladly recommend.

You could, like me, create your own keyboard layout. I have based mine on a swedish version of Dvorak, with more convenient placement of special characters common to programming. I’m not sure I want to recommend creating your own layout though, at least not if you’re a Windows user. One thing I’ve had problems with is that certain IDEs have been shadowing parts of my layout, forcing me back to qwerty and my old-style typing. And, you’ll need your own layout installed, which is a problem if you’re using computers that belong to others.

Whether you decide to create your own layout or not, be sure to learn touch typing. You’ll be grateful you did.

Previous posts in the Tools of The Effective Developer series:

  1. Tools of The Effective Developer: Personal Logs
  2. Tools of The Effective Developer: Personal Planning
  3. Tools of The Effective Developer: Programming By Intention
  4. Tools of The Effective Developer: Customer View
  5. Tools of The Effective Developer: Fail Fast!
  6. Tools of The Effective Developer: Make It Work – First!
  7. Tools of The Effective Developer: Whetstones
  8. Tools of The Effective Developer: Rule of Three
Categories: time-optimizing, tools Tags:

Tools of The Effective Developer: Rule of Three!

December 3rd, 2007 2 comments

I’m an impatient person, of the kind that are comfortable with making quick decisions on loose grounds, but prepared to change when more information gets available. This attitude has served me well, but also put me in trouble when important decisions were made too hastily. That’s why I always use The Rule of Three nowadays.

I first came across this version of The Rule of Three in Johanna Rothman and Esther Derby’s excellent book, Behind Closed Doors. The idea is to brainstorm solutions to a given problem, and not stop until you have at least three options to choose from. Listing the pros and cons of each solution helps you make a good decision.

With The Rule of Three I’m forced to think broader. I need to widen my view to find possible solutions other than the first that springs to mind. I’ve found that this process makes me explore the original solution better, and the risk of overlooking a good option is greatly reduced. Also, two different solutions can sometimes be combined into a new, even better one.

The Rule of Three can be applied in many ways, within a group or by yourself. It’s a cheap way to build better foundations for your decisions. That’s why I embrace The Rule of Three.

Previous posts in the Tools of The Effective Developer series:

  1. Tools of The Effective Developer: Personal Logs
  2. Tools of The Effective Developer: Personal Planning
  3. Tools of The Effective Developer: Programming By Intention
  4. Tools of The Effective Developer: Customer View
  5. Tools of The Effective Developer: Fail Fast!
  6. Tools of The Effective Developer: Make It Work – First!
  7. Tools of The Effective Developer: Whetstones

Support Your Favorite Small Software Vendor Day

December 1st, 2007 2 comments

I support the initiative of Jeff Atwood who declared this day to be the “Support Your Favorite Small Software Vendor Day“.

Categories: blogging, tools Tags: