QuickCheck is a Haskell library for software testing. It generates test cases and validates them against assertions provided by the programmer.
Questions tagged [quickcheck]
422 questions
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QuickCheck to Generate from Static Permutations List
Say that I have the data types:
data A = A1 | A2 | A3
data B = B1 A | B2 A
I can easily generate a list of all possibilities of B. I want to test all possible permutations, but I still want to use QuickCheck to spit out all the elements of the…
GreenSaguaro
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Generate edges from an Arbitrary list of nodes
data Edge v = Edge {source :: v, target :: v}
deriving (Show,Eq,Ord)
data Graph v = Graph {nodes :: Set v, edges :: Set (Edge v)}
deriving Show
instance Arbitrary v => Arbitrary (Edge v) where
arbitrary = do s <-…
ohiohai
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?SUCHTHAT vs ?IMPLIES in quickcheck
In Triq, PropEr, Quickcheck in Erlang what is the difference between using a ?SUCHTHAT property and the ?IMPLIES?
From what understand they are both specializations of the values produced by generators.
Andriy Drozdyuk
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Generating a random rule for property based test
I am using Triq (erlang quickcheck) and I am having trouble generating a set of nice rules for my program.
What I want to generate are things that looks like this:
A -> B
where I would like to provide A and the size of B, with latter not having any…
Andriy Drozdyuk
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1 answer
Generate events/commands using a property based testing tool?
As I understand it, most property testing tools operate at the level of functions. Given a set of arguments, such tools will generate random input and test output against some invariant.
I have read that ScalaCheck is now starting to include…
Shahbaz
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QuickChecking simple Functors: Is defining an Arbitrary instance necessary ? Why ? How?
I'm doing exercise with Functors and QuickCheck.
I have a super simple Functor, whose composition law I wish to quickCheck.
The Functor is simply an Identity a.
This is the code I have so far:
import Data.Functor
import Test.QuickCheck
newtype…
Stephane Rolland
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Quickcheck for runtime errors
I have interest in using the quick check library but it seems that it is designed to test properties. What I would like to do is generate random data for my defined data types and test functions I have written. I do not care about what the result…
44701
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4 answers
remove zero from infinite float list
I want to sample from an infinite list of floats for QuickCheck consumption. However, as I intend to use division, I want to remove zero from that list. It is such a conceptually simple problem I was wondering if I could do it with a list…
dmvianna
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How to print the test seed in Haskell's test-framework?
The test-framework docs state that it supports "Reporting of the seed used upon a failed QuickCheck run, so you can reproduce the failure if necessary." However the default output does not display this, and I cannot find any command line option that…
Will Sewell
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Generating arbitrary `JointList` with concrete types
I am writing tests for one of the exercises of this course homework.
In this homework the following data type is defined:
data JoinList m a = Empty
| Single m a
| Append m (JoinList m a) (JoinList m a)
…
Damian Nadales
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Arbitrary instance for StdGen
Please define:
instance Arbitrary StdGen where
arbitrary = undefined
shrink = undefined
Why is this not defined in the standard library? Are there some pitfalls I should avoid, is it even possible?
xiaolingxiao
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How do I call a constructor that may fail, especially when implementing 'Read' and 'Arbitrary'?
I have a "public safe" that may fail with a (potentially informative) errors:
data EnigmaError = BadRotors
| BadWindows
| MiscError String
instance Show EnigmaError where
show BadRotors = "Bad rotors"
show…
orome
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Can I generate arbitrary strings, and avoid repeating specifications in QuickCheck?
Given
data MyType = MyType ...
makeMyType :: String -> String -> String -> MyType
-- ...
type StringThing = String
where the strings that makeMyType expects are (respectively):
a - delimited string of some custom strings (e.g.,…
orome
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2 answers
Compare two functions using quickcheck to generate positive integers
I have the following Haskell functions:
expM :: Integer -> Integer -> Integer -> Integer
expM x y = rem (x^y)
And
exMME :: Integer -> Integer -> Integer -> Integer
exMME b 0 m = 1
exMME b e m = exMME' b e m 1 0 where
exMME' b e m…
Phaeton
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2 answers
Uniqueness and other restrictions for Arbitrary in QuickCheck
I'm trying to write a modified Arbitrary instance for my data type, where (in my case) a subcomponent has a type [String]. I would ideally like to bring uniqueness in the instance itself, that way I don't need ==> headers / prerequisites for every…
Athan Clark
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