Plot twist: they used a script to generate that code.
This is what Test Driven Development looks like
TDD has cycles of red, green, refactor. This has neither been refactored nor tested. You can tell by the duplication and the fact that it can’t pass all test cases.
If this looks like TDD to you, I’m sorry that is your experience. Good results with TDD are not guaranteed, you still have to be a strong developer and think through the solution.
As the existing reply stated, there are only ever finitely many tests.
My issue with TDD is that it pretends to drive the final implementation with tests, but what is really driving the implementation is the monkey at the keyboard thinking, “testing for evenness should be done with the modulo operation,” not exhaustive tests.
The monkey at the keyboard thinking is what software development is. When faced with a failing test, you make it pass as simply as possible, and then you summon all your computer science / programming experience to refactor the code into something more elegant and maintainable.
In this case that is using math to check if the input is divisible by two without a remainder. If you don’t know how that works, you’re going to have a bad time, like the picture in this post.
TDD doesn’t promise to drive the final implementation at the unit level, but it does document how the class under test behaves and how to use it.
When faced with a failing test, you make it pass as simply as possible, and then you summon all your computer science / programming experience to refactor the code into something more elegant and maintainable.
Why bother making it pass “as simply as possible” instead of summoning all that experience to write something that don’t know is stupid?
TDD doesn’t promise to drive the final implementation at the unit level
What exactly does it drive, then? Apart from writing more test code than application code, with attendant burdens when refactoring or making other changes.
The rhythm of TDD is to first write a failing test. That starts driving the design of your production code. To do that you need to invoke a function/method with arguments that responds with an expected answer.
At that point you’ve started naming things, designing the interface of the unit being tested, and you’ve provided at least one example.
Let’s say you need a method like
isEven(int number): Boolean. I’d start with asserting 2 is even in my first test case.To pass that, I can jump to
number % 2 == 0. Or, I can just returntrue. Either way gets me to a passing test, but I prefer the latter because it enables me to write another failing test.Now I am forced to write a test for odd input, so I assert 3 is not even. This test fails, because it currently just returns
true. Now I must implement a solution that handles even and odd inputs correctly; I know modulus is the answer, so I use it now. Now both tests pass.Then I think about other interesting cases: 0, negative ints, integer max/min, etc. I write tests for each of them, the modulus operator holds up. Great. Any refactoring to do? Nope. It’s a one-liner.
The whole process for this function would only add a few minutes of development, since the implementation is trivial. The test runtime should take milliseconds or less, and now there is documentation for the next developer that comes along. They can see what I considered (and what I didn’t), and how to use it.
Tests should make changing your system easier and safer, if they don’t it is typically a sign things are being tested at the wrong level. That’s outside the scope of this lemmy interaction.
Either way gets me to a passing test, but I prefer the latter because it enables me to write another failing test.
But you could just write that failing test up front. TDD encourages you to pretend to know less than you do (you know that testing evenness requires more than one test, and you know the implementation requires more than some if-statements), but no-one has ever made a convincing argument to me that you get anything out of this pretence.
Tests should make changing your system easier and safer, if they don’t it is typically a sign things are being tested at the wrong level
TDD is about writing (a lot of) unit tests, which are at a low-level. Because they are a low-level design-tool, they test the low-level design. Any non-trivial change affects the low-level design of a component, because changes tend to affect code at a certain level and most of those below it to some degree.
When you say “it can’t pass all test cases”, what do you imagine the tests look like?
In a world where this needs to be solved with TDD there are a few approaches.
If you were pair programming, your pair could always create a new failing test with the current implementation.
Realistically I would want tests for the interesting cases like zero, positive even, negative even, and the odds.
Another approach would be property based testing. One could create sequence generators that randomly generate even or odd numbers and tests the function with those known sequences. I don’t typically use this approach, but it would be a good fit here.
Really in pair programming, your pair would get sick of your crap if you were writing code like this, remind you of all the work you need to get done this week, and you’d end up using modulus and move on quickly.
If you were pair programming, your pair could always create a new failing test with the current implementation.
But I’m not pair programming. And you can’t always create a new failing test because
intis a finite type. There are only about 4 billion cases to handle.Which might take a while to type up manually, but that’s why we have meta-programming: Code that generates code. (In C++ you could even use templates, but you might run into compiler recursion limits.)
More to the point, the risk with TDD is that all development is driven by failing test cases, so a naive approach will end up “overfitting”, producing exactly the code required to make a particular set of tests pass and nothing more. “It can’t pass all test cases”? It doesn’t have to. For TDD, it only needs to pass the tests that have actually been written. You can’t test all combinations of all inputs.
(Also, if you changed this function to use modulus, it would handle more cases than before, which is a change in behavior. You’re not supposed to do that when refactoring; refactoring should preserve semantics.)
Read the article about property based testing. It is the middle ground between what you are describing and practicality.
I often pair with myself, which sounds silly but you can write failing tests by yourself, it just isn’t as fun.
Unittest in Python, enjoy! If you pass it with a function like the one in OPs picture, you have earned it.
import unittest import random class TestOddEven(unittest.TestCase): def test_is_odd(self): for _ in range(100): num = random.randint(0, 2**64 - 1) odd_num = num | 1 even_num = num >> 1 << 1 self.assertTrue(is_odd(odd_num)) self.assertFalse(is_odd(even_num)) def test_is_even(self): for _ in range(100): num = random.randint(0, 2**64 - 1) odd_num = num | 1 even_num = num >> 1 << 1 self.assertTrue(is_even(even_num)) self.assertFalse(is_even(odd_num)) if __name__ == '__main__': unittest.main()I don’t want unseeded randomness in my tests, ever.
Seed the tests, and making these pass would be trivial.
The right tool for the right job ¯\(ツ)/¯
The right tool here is tests at a level higher than machine code instructions that have been in CPUs since the 70s. Maybe TDD practice is not to test at this level, but every example of TDD sure tends to be something similar!
what’s the humour supposed to be
It’s a common challenge, such as in interviews, to write code that can return if a number is even or odd.
Does that make it funny?
Seeing as how pirate poses himself as a very knowledgeable guy who’s valued info should help get you into the industry, yes. That makes it hilarious, in fact.
The screenshot isn’t real though
That’s what i get for bandwagoning, oops
Oh, I see. Who is that?
Yes because that’s the dumbest smartest way to do it?
It’s an old joke though, I’ll give you that.
Throwback to when someone shared the OG version of this meme to my uni chat, I replied with "Oh you can simply do
def is_even(n: int) -> boolean: if n > 0 return not is_even(n - 1) elif n < 0 return not is_even(n + 1) else return TrueAnd instead of laughing at the joke the TA in the chat said “When you start getting internships you’ll do
n % 2” like I was being serious.Yeah but did you know he worked for Blizzard tho
def is_even(num): if num == 1: return False if num == 2: return True raise ValueError(f'Value of {num} out of range. Literally impossible to tell if it is even.')def is_even(num): num = num & 1 if num == 1: return False if num == 2: return True raise ValueError(f'what the fuck')If you’re waiting for “num & 1 == 2”, you’re going to be very disappointed
Oh shit, gotta check the negative numbers as well!
You could use a loop to subtract 2 from the number until it equals one or zero
Or literally just look at its binary representation. If the least significant digit is a “1”, it’s odd, if “0”, it’s even. Or you can divide by 2 and check for a remainder.
Your method is just spending time grinding away CPU cycles for no reason.
Sorry we’re not all fucking math nerds like you who knows words like “significant” or “binary” or “divide”, Poindexter. Some of us make do with whatever solution is available!
We know you were being satire. IMO it is of decent manner if you add “/s” to be explicit so when responding a serious reply, because this is not a satire comment chain.
Sorry we’re not all fucking satire nerds like you who knows words like “serious” or “satire” or “/s”, Poindexter. Some of us make do with whatever solution is available!
What should all the non binary people do then you bigot
Wasn’t the fun the CPU cycles we wasted along the way?
are you my TA that I mentioned in the other comment
Maybe. And I can’t blame it on not having had coffee when I made the comment. Just me being completely oblivious to a joke.
Oh. I thought that was Elixir until I zoomed in.
I’m partial to a recursive solution. Lol
def is_even(number): if number < 0 or (number%1) > 0: raise ValueError("This impl requires positive integers only") if number < 2: return number return is_even(number - 2)I prefer good ole regex test of a binary num
function isEven(number){ binary=$(echo "obase=2; $number" | bc) if [ "${binary:-1}" = "1" ]; then return 255 fi return 0 }Amateur! I can read and understand that almost right away. Now I present a better solution:
even() ((($1+1)&1))(I mean, it’s funny cause it’s unreadable, but I suspect this is also one of the most efficient bash implementations possible)(Actually the obvious one is a slight bit faster. But this impl for
oddis the fastest one as far as I can tellodd() (($1&1)))woah your bash is legit good. I thought numeric pretexts needed
(( blah )), but you’re ommiting the $ like an absolute madman. How is this wizardy possibleSee:
man bash, “Compound Commands” and “Shell Function Definitions”Oh I see it, but for some reason I was taught to always use
(( arith ))instead of(( arith ))and I guess I’m just wondering what the difference isThe difference is that
((is a “compound command”, similar to[[(evaluate conditional expression), while(( ))is “aritmetic expansion”. They behave in almost exactly the same way but are used in different contexts - the former uses “exit codes” while the latter returns a string, so the former would be used where you would expect a command, while the latter would be used where you expect an expression.This is similar to how there is
(compound command (run in a subshell), and$( )(command substitution). You can actually use the former to define a function too (as it’s a compound command):real_exit() { exit 1; } fake_exit() ( exit 1 )Calling
real_exitwill exit from the shell, while callingfake_exitwill do nothing as theexit 1command is executed in a separate subshell. Notice how you can also do the same in a command substition (because it runs in a subshell):echo $(echo foo; exit 1)Will run successfully and output
foo.It is another one of those unknown, very rarely useful features of bash.
amazing, thanks!
I’m waiting for a code golf style solution now.
I don’t think there’s much to codegolf. The “obvious” solution (
even() (($1%2))) is both shorter and faster. Don’t think it can be optimized much more.
If your codebase is closed source there’s no risk of that happening, if it’s open source there’s nothing you can do about it.
Either way there’s no use worrying.
this is like the making chess one
Would this be a case of modulo saving the day?
Like: If Number modulo 2 = 0, true
This has to be taken out of context
well that’s the joke, isn’t it
I mean, is it a joke? Because i have no context other than, after making a bad opinion known, there is a lot of talk about his code being terrible. So i guess this is fabricated then yea?
oh. is it assumed we know who the person is? i have no idea who that is.
I am more amazed that he didn’t stop at 10 and think “damn this is tiresome isn’t there a one liner i could do?”. I want to know how far he went. His stubbornness is amazing but also scary. I haven’t seen this kind of code since back in school lol lol lol
That code is so wrong. We’re talking about Jason “Thor” Hall here—that function should be returning 1 and 0, not booleans.
If you don't get the joke...
In the source code for his GameMaker game, he never uses
trueorfalse. It’s always comparing a number equal to 1.Frankly, it’s what I did, too, after coming out of Uni-level C.
My code was goddamn unreadable.
I am working with C in embedded designs and I still use 1 or 0 for a bool certain situations, mostly lines level.
For whatever pea-brained reason, it feels yucky to me to set a gpio to true/false instead of a 1/0.
GPIOs are usually controlled by a single bit of a register anyway. Most likely you need to do something like:
// Set high PORTB |= 1 << PINB5; // Set low PORTB &= ~(1 << PINB5);I am a lazy dev (not really, clients always want fast code), so I use the provided HAL libraries 99.9% of the time.
But I have seen code where someone would write something like
gpio_write(PIN_X, true)and it always stood out to me.
Define on as true or something? Or maybe that’s more confusing. I’m not a C dev so I’m not gonna pretend to understand idiomatic microcontroller code lol.
It’s the same for a lot of people. Beginners are still learning good practices for maintainable code, and they’re expected to get better over time.
The reason people are ragging on PirateSoftware/Jason/Thor isn’t because he’s bad at writing code. It’s because he’s bad at writing code, proclaiming to be an experienced game development veteran, and doubling down and making excuses whenever people point out where his code could be better.
Nobody would have cared if he admitted that he has some areas for improvement, but he seemingly has to flaunt his overstated qualifications and act like the be-all, end-all, know-it-all of video game development. I’m more invested in watching the drama unfold than I should be, but it’s hard not to appreciate the schadenfreude from watching arrogant influencers destroy their reputation.
He’s totally one of those people that’s sort of attractive and has an authoritative voice so s lot of people have probably folded to him in arguments through his life. I don’t like making generalizations like that about people but this isn’t the first time he’s acted like this. The one that really took the cake was the whole hardcore WoW raid debacle.
The TL;DR is, as well as not trying to really spend time on the parts that don’t matter, he did some things that may or may not have been the right thing to do in the situation depending on your perspective. But whenever any of his guild mates or other viewers would criticize him he’d be so adamant that no, he didn’t do anything wrong, he did exactly what he was supposed to do, etc. People would even explicitly tell him “hey, what’s pissing us off now isn’t that you did it, it’s that you’re so adamant you couldn’t have possibly made a mistake, you’re not willing to see our perspective. You’re not willing to admit that maybe you could’ve been wrong. You’re not willing to apologize.” And still, his reaction to this was to triple down and just insist he didn’t do anything wrong.
Like I literally even saw a clip of him talking to someone and he said “a lot of people think I’m being condescending when really I’m just providing context.” And the guy talking to him points out “yeah, it’s a problem that you think anyone disagreeing with you doesn’t understand the situation, it’s like you think they’re stupid.” It’s like it short circuited his brain. It’s like he’d never considered it.
So yeah, I have a pretty low opinion of him. But I also recognize that maybe all these clips are taken out of context, who knows. It’s not like my opinion really matters. I don’t work with him or know him. I don’t care about streamers. I don’t really watch them.
I want to assess coders by lines written! The more the better!
