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In other words, do you spend time anticipating errors and writing code to get around these potential issues, or do you write the code as you see fit and then work through any errors on an issue by issue basis?
I've been thinking a lot about this lately and I'm very much a reactive person. I write my code, give it a whirl, go back correct error and repeat until application works as expected. However a friend of mine offered that he spends time thinking how each line is interpreted and fixes errors before they occur.
I must point out that re-active is pure PRE-live. I definitely make sure my application is working before it goes live.
There should always be a balance.
Too many error checking is slow and leads to garbage code. Not enough error checking makes your program crash on edge cases which is not very good to discover after having it shipped.
So you decide how reliable some piece of code should be and implement error checking accordingly. Some test utility can be not very reliable - less error checking. A COM server meant to be used by a third party search service in deep background should be super reliable - much more error checking.
I think asking this in isolation is kinda weird, and very subjective, however there are obviously a bunch of techniques that permit you to do each. I tend to use these two:
Test-driven development (this would seem to be proactive)
Strong, static typing (reactive, but part of a tight iterative development cycle, as in, it's enforced by my ML compiler, and I compile a lot)
Very occasionally I swerve into the world of formal verification of programs. That's definitely "reactive", but if you think a little more up-front, it tends to make the verification easier.
I must also say that I value a lot of up-front thought in programming. The easiest way to avoid bugs is to not write them in the first place. Sometimes it's inevitable, but often a little more time spent thinking about the problem can lead to better-quality solutions, and then the rest can be taken care of using the kinds of automated methods I talked about above.
I usually ask myself a bunch of what-ifs when coding, like
The user clicks the button, what if they didn't select a date?
The user is typing in the search box, what if they try to type html in there?
My label text depends on a value from a shared drive, what if it's not mapped?
and so on. By doing this I've found that when the application does go live, there are a ton fewer errors and I can focus on fixing more obscure bugs instead of correcting conditions that should have been in place to begin with.
I live by a simple principle when considering error-handling: garbage in, garbage out. If you don't want any garbage (e.g. invalid input) messing up your software, you have to find all the points in your software where it can get in and handle it. Of course, the more complicated your software is, the harder it is to find every point of entry, but I feel that the more you do up front the less reactive you will need to be later on.
I advocate the proactive approach.
I try to write the code in that style which results in maintainable and reliable code
I use the defensive programming techniques to prevent stupid errors in code due to my loss of attention and similar
I design the database model according to the fortress principle, SQL code checking for results after each singular operation
I think of potential problems that can happen with that part of the code and I account for that. Not for every possibility but for major ones I can think of right now.
This usually results in software operating rather smoothly. At times it even surprises me but that was the intended goal, so here we are.
IMHO, the word "Error" (or its loose synonym "bug") itself means that it is a program behavior that was not foreseen.
I usually try to design with all possible scenarios in mind. Of course, it is usually not possible to think of all possible cases. But thinking through and allowing for as many scenarios as possible is usually better than just getting something working as soon as possible. This saves a lot of time and effort debugging and redesigning the code. I often sit down with pen and paper for even the smallest of programing tasks before actually typing any code into my editor.
As I said, this will not eliminate all errors. For me it pays off many times over in terms of time spent debugging. Another benefit is that it results in a more solid and maintainable design with fewer bugfixing hacks and special cases added on later. But in any case, you will have to do a lot of debugging after the code is done.
This does not apply when all you want is a mockup or rapid prototype. Also practical constraints such as deadlines often makes a thorough evaluation difficult or impossible.
What kind of programming? It's impossible to answer this in any general way. (It's like asking "do you wear a helmet when playing?" -- well, playing what?)
At work, I'm working on a database-backed website. The requirements are strict, and if I don't anticipate how users will screw it up, I'm going to get a call at some odd hour of the day to fix it.
At home, I'm working on a program ... I don't even know what it'll do yet. I can't deal with 'errors' because I don't know what 'an error' is in this context, because I don't know what correct behavior is going to be. The entire purpose of the program can and frequently does change on a timescale of minutes to hours, so even a couple minutes spent thinking about errors this early is a complete waste of time. (It's even worse than browsing SO, since error-handling adds lines of code.)
I guess the only general answer is "I do what makes sense in terms of saving time in the long term", which is, after all, the whole reason to use machines to do work for us.
In may Daily Job i come across this Dilemma :
"Stable System Vs Better Design"
In routine job when i am fixing some module, When i see bad design
-> Badly written code
-> Badly Written Algorithm
-> Optimization possible
I would prefer to fix these also along with issue i am fixing
But many people opposes my changes a few supports, People who opposes will say
"You should be business oriented if system is stable, If you change some thing may cause regression, Hence do not favor business"
some time :
you will see your own written code after 6 months, Always you will see some improvment opportunity in this
While who support will say:
This is continual improvement and system will be more stable
So i would like to know what you people think
If applicable, write a unit test (or several, to cover edge cases). This gives you the confidence to refactor and know that you haven't broken anything.
Of course, if the code is tightly coupled (or spaghetti!), that's going to be a problem.
If it ain't broken don't fix it - wrap it. Isolate the modules as much as you can without changing its implementation; they should be touched (fixed, improved) when / if a real need arises.
My opinion would be not to fix the old code if it looks not perfect unless the way it is written is interfering with your current task at hand.
Most of the code is written badly. It is a matter of fact. If you're not in a perfect team with the perfect understanding of quality value and the agreement on the approach to achieve and keep this quality level, your optimizations will not change the big picture. You may fix something now but the next guy will make the mess of the things again.
I have came to the conclusion that in this industry if its not broken, don't fix it unless there is a damn good reason to.
If you know the application inside out, or have comprehensive unit tests and time to test the application in a non-productive environment, go for it. Otherwise, do it just when it's necessary.
Both are correct and there is no easy way out.
If you don't fix problems as you encounter them, not all problems will be fixed.
If you break something with a fix that is not 100% related to the issue you're currently working on, then people will hate you.
On the other hand, if you fix some innocent code (or rather code that looks innocent) and it breaks in unexpected ways, you've found something valuable: Brittle code. Brittle code is usually something that no one dares to touch. But to make your product more stable, you must get rid of such code. The first step on this road is to find it.
I have to admit that such fixes cause a lot of "unnecessary" friction in the team. People will yell at you when you touch brittle code because they are afraid. Often, this code will blow into the face of your customers, so you will get heat from all kinds of directions.
So it really depends on how much pain you want to cause and what you're willing to endure. If you fix everything as you encounter it, the code will be better by the end of the year. But it often is worse by the end of the day.
I want to second all the "if it ain't broke, don't fix it" answers, but with a relevant link...
Things You Should Never Do, Part 1 - Joel Spolsky
In essence - sometimes that incomprehensible code is actually a necessary bugfix that you have no chance to understand.
On the one hand, changing code that's already more-or-less working can run the risk of breaking things, and it can easily become an all-consuming task.
On the other hand, leaving bad code alone for fear of breaking things can stifle new development, due to the burden of maintaining bad code.
Sometimes code looks bad because it has to deal with complicated corner cases, as Joel Spolsky points out, and rewriting it will create bugs by failing to cover those corner cases. Sometimes code looks bad because it really is bad, and rewriting it can fix bugs that you didn't even know were there. Experience with your code base should help you determine which code is which.
In Boy Scout Check-Ins, Jeff Moser discusses the idea of "always leaving the campground cleaner than you found it." Always leave the codebase cleaner than you found it, even if you can't fix everything; those little improvements add up over time.
As was said in this answer, unit tests are a good thing. Working Effectively with Legacy Code, by Michael Feathers, is a great resource on this topic.
I personally have a tendency to spend time fixing stuff rather than getting on with the required task. Unfortunately it is all too easy to start fixing what looks like an easy problem and unravelling a huge mess that you then wish you hadn't.
I have also worked with people who are the other way round, and can live with the bad bits as long as it gets the job done.
More often than not, you can spend ages 'getting something right' to make it easier to work with in the future and you'll find that code is never reused in the future.
I think the main thing is to have a balance of views on your team, discuss things regularly with others and ultimately, meet the requirements for your project, since it's the customer paying the bills.
Be constructive about any problems you find - don't just pick holes for the sake of it! Team code reviews help improve bad code over time as poor coders will start to understand how to make good code.
I would advise marking bad code with 'TODO' comments and then coming back to fix it later time/budget allows. At least you've got a flag for potential problem areas then, without having to (possibly) waste time on a fix that's not required there and then.
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We've all been there. You have written some code and unit tests, the tests all pass, and the code is decent (nothing's perfect, right?). Then, someone who is sure that they know better than you comes along and decides to change your code or the interfaces to your code just because he/she does not like the variable/class names that you used. No "real" refactorings, no real optimizations, no real improvement -- just different words -- not necessarily better words, just different.
My real problem with this is that (a) its a waste of time and (b) it shows a blatant disrespect for the fellow developer that wrote the code in the first place.
My visceral response is to lash out, but that's counter productive. Instead, I though that I might wright a paragraph or two as sort of a "Charter" or "Philosophy" that is adopted for the project. I'm wondering if anyone else has tried this, and if so, was it successful?
After looking at the initial comments below (which are appreciated), I think that my problem is primarily that this change broke the build for code that was already working. So time needed to be spent to fix the code for what was (in my opinion) a non value-added change.
-- Thanks
...decides to change your code or the
interfaces to your code just because
he/she does not like the
variable/class names that you used.
My real problem with this is that (a)
its a waste of time and (b) it shows a
blatant disrespect for the fellow
developer that wrote the code in the
first place.
My visceral response is to lash out...
I see some VERY CONCERNING things in those statements.
naming is REALLY, REALLY important. It is worth rewriting code to get it correct.
It is not YOUR code
How is it disrespectful?
You are taking it too personally.
I once worked with someone who freaked out when I made changes to "his" code. His code as horrible; it was buggy and unmaintainable. He was always staying late, fighting fires and breaking things - basically a negative contributor. I rewrote all his bad code for a big piece of functionality for a project one weekend and when he came back in on monday had a hissy fit. I am not saying your stuff is horrible, but maybe you need to calm down and be more objective about it.
Don't take it so personally. Step back and think about it - maybe "your" code needed fixing
We might be able to give better answers if you posted the code and changes, or at least some better idea of the situation with an example or two.
EDIT:
After seeing the code change and finding out that the build was broken, I am going to have to change the tone of this answer. I understand Steve's frustration - and i agree - that is not a good change. It makes a specific typedef more general and not very descriptive any more.
While I think some of my points are valid, in this case it looks like the changes were not appropriate.
The issue of code "ownership" is irrelevant. If the code changes are useless then everyone on the team should not be happy. If they are good changes then everyone should be happy about it. If there is a difference of opinion then you all need to find a common ground.
Breaking the build is not a good thing.
Steve, sorry if I came down harsh - it looks like in this instance you are justified in your frustration, but not because it is "your" code.
One thing that might help in this sort of situation is to require code reviews for all changes. People are less likely to make pointless changes if someone else has to review it first. If they can actually convince another developer that their change should go in then maybe it isn't so pointless after all.
Heey,
Guys! WE all need TO TALK!
Just sit together and TALK! There are always reasons to change and there are always reasons NOT to.
Decide together!
Don't just go to StackOverflow or a forum and say ask this kind of questions.
The new dev does it - he gets responses from community probably positive (yeahh, bad code should be refactored).
The current dev does it - he gets responses from the community too: "What an idiot could do such kind of changes!"
And the result is: Counterproductive, destructive, offensive environment for a long time.
Who wants it?
Just put your arguments on the table and that's it.
New dev needs some introduction too.
Old dev needs to listed TOO.
This should be collaborative work AND not pissing each other off.
Decide together, talk, as THE TEAM.
And... better ask questions like "How is it better to refactor this?"
Cheers.
In any software development team with a size > 1, standardization is key. Not only for each developer to understand the other's code, but so that the people that come along in 2 years, 5 years and 10 years can look at any part of the code and see a clear and consistent pattern. Will you... and the rest of the team... seriously still be there, working on this project, years down the line?
If you both "just have your way of doing things" and there is no formal standard for the project/company, I suggest you work with the team and/or your boss to suggest a formal standard be adopted. There are many standards already published for the various environments that you can use either as the standard, or as a starting point.
If there is a formal standard, everyone on the team is obligated to follow it... no matter how much "better" they think their way is.
So much for the hard skills.
Now on the soft skills side...
You and your colleague need to develop a healthy relationship, or decide to work in different places. Tit-for-tats that result in people feeling that they want to lash out will make everyone unhappy, not to mention gravely jeopardize the project everyone is being paid to complete. Look for a person you both respect (maybe your boss, maybe a respected and level-headed senior member of the team, maybe HR if you have a good HR department). Explain to that person what the problem is and that it makes you feel unvalued and disrespected. Ask for help talking through the situation with your colleague and agreeing to a better way of working together.
Finally, you need to be open to the possibility that your colleague may be making subjectively correct changes, even if the manner he's doing it in offends you. Separate the correct coding from the correct interpersonal interactions. Do the right thing for the project.
Well if that guy is going to maintain your code, let him do whatever he wants to.
Just remember that it is not "your" code. The code belongs to the company for which you work for. You wrote the code and you got paid for it. Let the Management do whatever they want to do with it.
Don't take things personally, move on.
Sometimes, changing names might be justified. It can be confusing if half the project refers to a person's sex, and then you check in some new code that refers to gender or something. Okay, this might be a bad example as technically they are two different things and their meaning is most likely still obvious. But if a project's code uses two different terms to refer to the same concept, it can be confusing.
Usually I try to leave people's code alone, unless I have some justification for refactoring. Luckily the same seems to go for my colleagues, so no, I have not had the need for writing such a charter yet.
How about using an automated build system, so when this person changes the code and breaks something the team will get an alert about it. This solves your problem with having to waste your time fixing something broken by someone elses change to your code. This way everyone will know that so and so made a change and broke the build, and can see for themself. The rule is "dont break the build".
You should be discussing this with the person who did it, in a non-threatening manner.
I believe every developer should take responsibility and hence own some of the code, but not all of the code. I understand the code that I've written better (irrespective of how good/bad it is) than any other guy that has ever seen it. Therefore the changes I make will be faster and less prone to error.
I don't mind anybody changing the code I've written later on, but I have a couple of conditions:
If you change the code and that causes something else to break, you are responsible for fixing it, not me.
If I don't agree with the changes you made I will change it back to the way I want it since I have to take responsibility for this piece of code in future.
Not all developers should be making changes to all the code, all the time. Only some of the time, for the purpose of getting to know the code (sharing knowledge).
I've never worked for an employer that endorses a "everyone can change anything any time" policy. Developers own certain parts of the code and they are asked specifically to make changes/refactor based on a development democracy.
You touch my code and break something, (1) you better have a good reason for the change that all developers agree with and (2) you better not leave broken things broken or ask me to go do the clean-up for you UNLESS you're my superior. I will humbly submit if that's the case.
I agree with Laurence that code reviews might help. This is an issue of how your team should work together. What might help is the notion of Egoless Programming - in a nutshell, considering the code as a joint product of the team, and trying to make decisions for the sake of the code rather than because of the programmer's ego. Your teammate violated the fourth commandment of egoless programming - "Don't rewrite code without consultation."
Maybe if your team is made aware of these principles, things will improve. I would try this.
Perhaps not completely on topic, but .... If you have developers who have the time to make changes to code just because they don't like the variable names used, then maybe the conversation should be about whether you have too many developers and which ones should be shown the door ... or how you're going to justify to management the bloated staff you have, especially in the current economic circumstances!
On occasion I've heard people discuss the benefits of keeping track of programming mistakes, if for no other reason than it increases awareness of common errors. I've started to keep a list of bugs that I find in my code, along with what could have led to them. The main question I have is this:
What information related to my mistakes should I be keeping
track of so that I can improve as a
programmer?
And a couple other questions related to this:
How do I use this information once I start logging my mistakes?
Is tracking mistakes truly beneficial?
This is only useful if you are actually vigilant with tracking and reviewing. When I was working on a team, no matter how much documented that for example our servers in the production environment were natted and would not be able to resolve their own domain names or public IP addresses, every 6 months, I'd get a call at 4 AM from the deployment team or dev team that a new developer was responsible for, and they either forgot or were unaware.
I remember a particular engineer who was repsonsible for deploying and he had paper checklists, we built him deployment tools that forced him to record his checklist, yet he would always forgot to set the connection string (resulting in the 4 am phone call). Point is it's only worth it if your going to use it vigilantly.
I've found the best way to use this is by implementing your rules into a code analyzer like fxcop.
I think what is more useful than keeping a log of individual mistakes is making sure you come away with a real understanding of why it was a mistake in the first place. Most mistakes stem from a lack of understanding about one thing or another, correct that understanding and you eliminate an entire set of potential mistakes in the future. If I would log anything it would be what I learned from the experience that I didn't know before, not the specifics of the mistake that was made which is likely to be of limited usefulness when you look back at it later.
what was the mistake
how can it be avoided
add the latter to an appropriate checklist, and refer to it as often as appropriate
I think tracking mistakes can be worthwhile, but in my experience it helps a lot to categorize them at some level.
Every programmer is going to make enough mistakes over the course of their career to fill an encyclopaedia. If you make a huge checklist out of all of them then you're never going to get any coding done because you'll eventually be spending all of your time going over your checklist. So: categorize your mistakes in some way that makes sense to you so you can rifle through your list looking at the most important mistakes for the sort of code you're currently working on.
Also, to add to the above as far as what to collect:
what are the symptoms of the mistake (so you can find it later)
how you actually solved it
Yes, tracking your personal mistakes is beneficial. Refer to the SEI for numerous data points (here's one at random). One such methodology is the Personal Software Process (PSP). It's too long to go into here, but here's a book about it. There's also this free SEI publication on PSP.
If you balk at SEI and think Agile is the way to go, you'll probably get better mileage out of a book like Clean Code: A Handbook of Agile Software Craftsmanship (publisher website).
Bottom line: disciplined developer = good, undisciplined developer = bad.
I would also want to ask the question of how much time would be required to accurately track the mistakes, and if that time could be better spent directly on improving the software instead. If you can do this in a minimal amount of time and are able to refer back to your records to prevent future mistakes, it may be valuable. In the long run though, I think it will be better to stick with an absolutely high level list of common mistakes you make.
I'd look for trends or similar types of errors that tend to recur. Once you're aware of the types of errors you make, you can be alert for them, or you can change your coding style to avoid them.
As an example, I worked very closely with my office-mate in a previous life. At one point I was halfway through my first sentence explaining some odd behavior, and he interrupted with, "increment your counter." I still double-check my loop counters today!
Instead of keeping a log of future mistakes, maybe you could review your bugtracker history, and try to find common types of errors which keep ocurring.
I'm so inspired I think I'll try this tommorow.
"What information related to my mistakes should I be keeping track of so that I can improve as a programmer?"
Read other people blogs. Write your own. You don't have to publish it. But you do have to turn each mistake into a story.
Don't drown this in metadata. This isn't amenable to a database or even a bug tracker. A mistake is a story where someone made a bad choice and recovered from it.
Here's your outline.
Context. What was going on.
Situation. The problem you were trying to solve.
What you did. Why it was bad.
What you should have done. Why it was better.
What changed. What you learned.
You should also record your successes in almost the same form.
Context. What was going on.
Situation. The problem you were trying to solve.
What you did. Why it was good.
What you learned.
When in doubt watch a movie. Seriously. Characters a confronted with choices, make mistakes and recover from those mistakes. That story line is the essence of drama. A mistake is the same thing.
Be careful what you log. Not every bad situation is a mistake. Some situations are inevitable or so far outside your control that nothing can be done about it.
Bad planning on someone else's part which puts you into panic-mode isn't your mistake. You can meticulously log everyone else's mistakes, but what's the point? If you're tracking what other people are doing, you should seek therapy.
Bad planning which provides inadequate budget, schedule or communication about changes may be a compound problem.
You didn't provide enough planning information up front.
In the scramble to cope, you made another mistake which lead to problem resolution and recovery.
In hindsight (which is always 20/20) you can see a decision which was wrong. However, at the time, it was based on best available information. That's not a mistake. Any sentence that begins "If we'd known that X..." is useless for mistake analysis. You can try to write a checklist of all the things you need to know next time you make that decision. But next time, you won't be making exactly that decision and some other piece of information will turn up missing.
Never call other people's actions mistakes.
Find the root causes. It's a root cause when it's something you can't control.
Don't retroactively call information that turned up missing a mistake.
I have been thinking the same thing. For the time being I keep a little spreadsheet with bugs I correct. The purpose of this is to make myself aware of the more common errors being made.
Hopefully I will start to see patterns and avoid making common errors over and over again.
I find that this makes my job more interesting, probably since I am an analytical person who likes to collect data and information in a structured manner.
You should try to relate the errors to use of inadequate tools, habits, methods or knowledge. In most cases you will find there would have been ways to catch the error earlier. Things like type-safety, unit-testing, code-review, coding standards, better API design, better documentation and working environment, comes to my mind.
I use JIRA with a custom workflow. For a bug, the last step before an issue is closed is a screen that allows me to select a "root cause". I've got a history of the root cause of every bug that's occurred in the last 3 systems I've built.
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One of our developers is continually writing code and putting it into version control without testing it. The quality of our code is suffering as a result.
Besides getting rid of the developer, how can I solve this problem?
EDIT
I have talked to him about it number of times and even given him written warning
If you can do code reviews -- that's a perfect place to catch it.
We require reviews prior to merging to iteration trunk, so typically everything is caught then.
If you systematically perform code reviews before allowing a developer to commit the code, well, your problem is mostly solved. But this doesn't seem to be your case, so this is what I recommend:
Talk to the developer. Discuss the consequences for others in the team. Most developers want to be recognized by their peer, so this might be enough. Also point out it is much easier to fix bugs in the code that's fresh in your mind than weeks-old code. This part makes sense if you have some form of code owneship in place.
If this doesn't work after some time, try to put in place a policy that will make commiting buggy code unpleasant for the author. One popular way is to make the person who broke the build responsible for the chores of creating the next one. If your build process is fully automated, look for another menial task to take care of instead. This approach has the added benefit of not pinpointing anyone in particular, making it more acceptable for everybody.
Use disciplinary measures. Depending on the size of your team and of your company, those can take many forms.
Fire the developer. There is a cost associated with keeping bad apples. When you get this far, the developer doesn't care about his fellow developers, and you've got a people problem on your hands already. If the work environment becomes poisoned, you might lose far more - productivity-wise and people-wise - than this single bad developer.
As a developer who rarely tests his own code, I can tell you the one thing that's made me slowly shift my behavior...
Visibility
If the environment allows pushing code out, waiting for users to find problems, and then essentially asking "How about now?" after making a change to the code, there's no real incentive to test your own stuff.
Code reviews and collaboration encourage you to work towards making a quality product much more than if you were just delivering 'Widget X' while your coworkers work on 'Widget Y' and 'Widget Z'
The more visible your work is, the more likely you are to care about how well it works.
Code review. Stick all of your dev's in a room every Monday morning and ask them to bring their most proud code-based accomplishment from the previous week along with them to the meeting.
Let them take the spotlight and get excited about explaining what they did. Have them bring copies of the code so other dev's can see what they're talking about.
We started this process a few months ago, and it's astonishing to see the amount of sub-conscious quality checks that take place. After all, if the dev's are simply asked to talk about what they're most excited about, they'll be totally stoked to show people their code. Then, other dev's will see the quality errors and publicly discuss why they're wrong and how the code should really be written instead.
If this doesn't get your dev to write quality code, he's probably not a good fit for your team.
Make it part of his Annual Review objectives. If he doesn't achieve it, no pay rise.
Sometimes though you do just have to accept that someone is just not right for your team/environment, it should be a last resort and can be tough to handle but if you have exhausted all other options it may be the best thing in the long run.
Tell the developer you would like to see a change in their practices within 2 weeks or you will begin your company's disciplinary procedure. Offer as much help and assistance as you can, but if you can't change this person, he's not right for your company.
Using Cruise Control or a similar tool, you can make checkins automatically trigger a build and unit tests. You would still need to ensure that there are unit tests for any new functionality he adds, which you can do by looking at his checkins.
However, this is a human problem, so a technical solution can only go so far.
Why not just talk to him? He probably won't actually bite you.
Make him "babysit" the build, and become the build manager. This will give him less time to develop code (thus increasing everyone's performance) and teach him why a good build is so necessary.
Enforce test cases - code cannot be submitted without unit test cases. Modify the build system so that if the test cases don't compile and run correctly, or don't exist, then the entire task checkin is denied.
-Adam
Publish stats on test code coverage per developer, this would be after talking to him.
Here are some ideas from a sea shanty.
Intro
What shall we do with a drunken sailor, (3×)
Early in the morning?
Chorus
Wey–hey and up she rises, (3×)
Early in the morning!
Verses
Stick him in a bag and beat him senseless, (3×)
Early in the morning!
Put him in the longboat till he’s sober, (3×)
Early in the morning!
etc. Replace "drunken sailor" with a "sloppy developer".
Depending on the type of version control system you are using you could set up check-in policies that force the code to pass certain requirements before being allowed to check-in. If you are using a sytem like Team Foundation Server it gives you the ability to specify code-coverage and unit testing requirements for check-ins.
You know, this is a perfect opportunity to avoid singling him out (though I agree you need to talk with him) and implement a Test-first process in-house. If the rules aren't clear and the expectations are known to all, I've found that what you describe isn't all that uncommon. I find that doing the test-first development scheme works well for me and improves the code quality.
They may be overly focused on speed rather than quality.
This can tempt some people into rushing through issues to clear their list and see what comes back in bug reports later.
To rectify this balance:
assign only a couple of items at a time in your issue tracking system,
code review and test anything they have "completed" as soon as possible so it will be back with them immediately if there are any problems
talk to them about your expectations about how long an item will take to do properly
Peer programming is another possibility. If he is with another skilled developer on the team who dies meet quality standards and knows procedure then this has a few benifits:
With an experienced developer over his shoulder he will learn what is expected of him and see the difference between his code and code that meets expectations
The other developer can enforce a test first policy: not allowing code to be written until tests have been written for it
Similarly, the other developer can verify that the code is up to standard before it is checked-in reduicing the nmber of bad check-ins
All of this of course requires the company and developers to be receptive to this process which they may not be.
It seems that people have come up with a lot of imaginative and devious answers to this problem. But the fact is that this isn't a game. Devising elaborate peer pressure systems to "name and shame" him is not going to get to the root of the problem, ie. why is he not writing tests?
I think you should be direct. I know you say that you've talked to him, but have you tried to find out why he isn't writing tests? Clearly at this point he knows that he should be, so surely there must be some reason why he isn't doing what he's been told to do. Is it laziness? Procrastination? Programmers are famous for their egos and strong opinions - perhaps he's convinced for some reason that testing is a waste of time, or that his code is always perfect and doesn't need testing. If he's an immature programmer, he might not fully understand the implications of his actions. If he's "too mature" he might be too set in his ways. Whatever the reason, address it.
If it does come down to a matter of opinion, you need to make him understand that he needs to set his own personal opinion aside and just follow the rules. Make it clear that if he can't be trusted to follow the rules then he will be replaced. If he still doesn't, do just that.
One last thing - document all of your discussions along with any problems that occur as a result of his changes. If it comes to the worst you may be forced to justify your decisions, in which case, having documentary evidence will surely be invaluable.
Stick him on his own development branch, and only bring his stuff into the trunk when you know it's thoroughly tested. This might be a place where a distributed source control management tool like GIT or Mercurial would excel. Although with the increased branching/merging support in SVN, you might not have too much trouble managing it.
EDIT
This is only if you can't get rid of him or get him to change his ways. If you simply can't get this behaviour to stop (by changing or firing), then the best you can do is buffer the rest of the team from the bad effects of his coding.
If you are at a place where you can affect the policies, make some changes. Do code reviews before check ins and make testing part of the development cycle.
It seems pretty simple. Make it a requirement and if he can't do it, replace him. Why would you keep him?
I usually don't advocate this unless all else fails...
Sometimes, a publicly-displayed chart of bug-count-by-developer can apply enough peer pressure to get favorable results.
Try the Carrot, make it a fun game.
E.g The Continuous Integration Game plugin for Hudson
http://wiki.hudson-ci.org/display/HUDSON/The+Continuous+Integration+Game+plugin
Put your developers on branches of your code, based on some logic like, per feature, per bug fix, per dev team, whatever. Then bad check-ins are isolated to those branches. When it comes time to do a build, merge to a testing branch, find problems, resolve, and then merge your release back to a main branch.
Or remove commit rights for that developer and have them send their code to a younger developer for review and testing before it can be committed. That might motivate a change in procedure.
You could put together a report with errors found in the code with the name of the programmer that was responsible for that piece of software.
If he's a reasonable person, discuss the report with him.
If he cares for his "reputation" publish the report regularly and make it available to all his peers.
If he only listens to the "authority", do the report and escalate the issue to his manager.
Anyway, I've seen often that when people are made aware of how bad they seem from outside, they change their behaviour.
Hey this reminds me of something I read on xkcd :)
Are you referring to writing automated unit test or manually unit testing prior to check-in?
If your shop does not write automated tests then his checking in of code that does not work is reckless. Is it impacting the team? Do you have a formalized QA department?
If you are all creating automated unit tests then I would suggest that part of your code review process include the unit tests as well. It will become obvious that the code is not acceptable per your standards during your review.
Your question is rather broad but I hope I provided some direction.
I would agree with Phil that the first step is to individually talk to him and explain the importance of quality. Poor quality can often be linked to the culture of the team, department and company.
Make executed test cases one of the deliverables before something is considered "done."
If you don't have executed test cases, then the work is not complete, and if the deadline passes before you have the documented test case execution, then he has not delivered on time, and the consequences would be the same as if he had not completed the development.
If your company's culture would not allow for this, and it values speed over accuracy, then that's probably the root of the problem, and the developer is simply responding to the incentives that are in place -- he is being rewarded for doing a lot of things half-assed rather than fewer things correctly.
Make the person clean latrines. Worked in the Army. And if you work in a group with individuals who eat a lot of Indian food, it wont take long for them to fall in line.
But that's just me...
Every time a developer checks something in that does not compile, put some money in a jar. You'll think twice before checking in then.
Unfortunately if you have already spoken to him many times and given him written warnings I would say it is about time to eliminate him from the team.
You might find some helpful answers here: How to make junior programmers write tests?
I'd be tempted to suggest elaborating a bit on what you've tried and what results you got as this may have changed a bit but here are my initial suggestions:
Is it any tests or comprehensive tests? Some may code blindly and do zero tests, but this is rather rare, IME. Usually there are some tests done but not enough to cover most of the cases that would be comprehensive testing.
Group dynamics may help. I'd assume he is part of a team and that the team's view may be of some help here. In a way this is trying to get peer pressure which is usually a bad thing but sometimes it can be used in good ways.
How well spelled out were the warnings? In a way this can seem childish but there is a chance that what you think of as testing may not be the same as his. Do you want nUnit tests, an excel spreadsheet, logs from his computer, or something else as proof of the existence and use of tests? From what you've described there isn't anything to confirm that he did understand what you meant, was going to use tests and provide evidence of doing so.
Check-in policy question. Some places, such as my current workplace, encourage committing often which can mean that one does commit code without tests. Is there a known, accepted and well-followed policy where you are? That's another aspect here.