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0 pointshitchstory1y ago0 comments

Id say if you think tests and types are doing the same thing in the same way you are badly abusing at least one of them.

One attacks the problem of bugs from the bottom up and the other from the top down. They both have diminishing returns on investment the closer they get to overlapping on covering the same types of bug.

The haskell bros who think tests dont do anything useful because "a good type system covers all bugs" themselves havent really delivered anything useful.

0 comments

yakshaving_jgt1y ago

> The haskell bros who think tests dont do anything useful because "a good type system covers all bugs" themselves havent really delivered anything useful.

Please don't do this. It's not constructive.

1 more reply

youerbt1y ago

I'm a Haskell bro and I love testing. You misunderstand me, though. All I say is that maybe _some_ of those tests deliver value by just making sure that code even runs, which is otherwise covered by types.

hitchstoryOP1y ago

When I do TDD (virtually every time i write a line of code) each test scenario isnt just a way to verify that the code is working, it's also a specification - often for a previously unconsidered edge case.

Throwing away the test means throwing away that user story and the value that comes with it.

youerbt1y ago

I believe you (other than tests being specifications, they are examples at best). But that doesn't change the fact that TDD looks more adopted in untyped languages, and that deserves an explanation.

Mine is that a lot of potential errors (typos, type mismatches) don't need to be exercised by running code in typed language.

Yours is... well, you don't really address it.

1 more reply

koolba1y ago

That’s exactly what those tests are for. When you no longer have to worry if you invoked .foo() or .fooTypo(), you eliminated one class of bug. Namely trying to run things that do not exist.

Maybe you meant to invoke .bar(), but at least we know thanks to type checks that the target exists.

j / k navigate · click thread line to collapse

0 pointshitchstory1y ago0 comments

Id say if you think tests and types are doing the same thing in the same way you are badly abusing at least one of them.

The haskell bros who think tests dont do anything useful because "a good type system covers all bugs" themselves havent really delivered anything useful.

0 comments

yakshaving_jgt1y ago

> The haskell bros who think tests dont do anything useful because "a good type system covers all bugs" themselves havent really delivered anything useful.

Please don't do this. It's not constructive.

1 more reply

youerbt1y ago

hitchstoryOP1y ago

Throwing away the test means throwing away that user story and the value that comes with it.

youerbt1y ago

I believe you (other than tests being specifications, they are examples at best). But that doesn't change the fact that TDD looks more adopted in untyped languages, and that deserves an explanation.

Mine is that a lot of potential errors (typos, type mismatches) don't need to be exercised by running code in typed language.

Yours is... well, you don't really address it.

1 more reply

koolba1y ago

That’s exactly what those tests are for. When you no longer have to worry if you invoked .foo() or .fooTypo(), you eliminated one class of bug. Namely trying to run things that do not exist.

Maybe you meant to invoke .bar(), but at least we know thanks to type checks that the target exists.

j / k navigate · click thread line to collapse