Test.Hspec

Hspec is a testing library for Haskell.

This is the library reference for Hspec. The User's Manual contains more in-depth documentation.

Types

type Spec = SpecWith ()

type SpecWith a = SpecM a ()

type ActionWith a = a -> IO ()

An IO action that expects an argument of type a.

class Example e

A type class for examples.

Instances

Example Bool

Example Property

Example Expectation

Example Result

Example (a -> Property)

Example (a -> Expectation)

Setting expectations

module Test.Hspec.Expectations

Defining a spec

describe :: String -> SpecWith a -> SpecWith a

Combine a list of specs into a larger spec.

context :: String -> SpecWith a -> SpecWith a

An alias for describe.

it :: Example e => String -> e -> SpecWith (Arg e)

Create a spec item.

A spec item consists of:

• a textual description of a desired behavior
• an example for that behavior

 describe "absolute" $ do
   it "returns a positive number when given a negative number" $
     absolute (-1) == 1

example :: Expectation -> Expectation

This is a type restricted version of id. It can be used to get better error messages on type mismatches.

Compare e.g.

 it "exposes some behavior" $ example $ do
   putStrLn

with

 it "exposes some behavior" $ do
   putStrLn

pending :: Expectation

Specifies a pending example.

If you want to textually specify a behavior but do not have an example yet, use this:

 describe "fancyFormatter" $ do
   it "can format text in a way that everyone likes" $
     pending

pendingWith :: String -> Expectation

Specifies a pending example with a reason for why it's pending.

 describe "fancyFormatter" $ do
   it "can format text in a way that everyone likes" $
     pendingWith "waiting for clarification from the designers"

before :: IO a -> SpecWith a -> Spec

Run a custom action before every spec item.

beforeWith :: (b -> IO a) -> SpecWith a -> SpecWith b

Run a custom action before every spec item.

after :: ActionWith a -> SpecWith a -> SpecWith a

Run a custom action after every spec item.

after_ :: IO () -> Spec -> Spec

Run a custom action after every spec item.

around :: (ActionWith a -> IO ()) -> SpecWith a -> Spec

Run a custom action before and/or after every spec item.

around_ :: (IO () -> IO ()) -> Spec -> Spec

Run a custom action before and/or after every spec item.

aroundWith :: (ActionWith a -> ActionWith b) -> SpecWith a -> SpecWith b

Run a custom action before and/or after every spec item.

parallel :: SpecWith a -> SpecWith a

Run examples of given spec in parallel.

Running a spec

hspec :: Spec -> IO ()

Run given spec and write a report to stdout. Exit with exitFailure if at least one spec item fails.