tasty- Modern and extensible testing framework

Safe HaskellNone




This module defines the main data types and functions needed to use Tasty.


Organizing tests

type TestName = StringSource

The name of a test or a group of tests

data TestTree Source

The main data structure defining a test suite.

It consists of individual test cases and properties, organized in named groups which form a tree-like hierarchy.

There is no generic way to create a test case. Instead, every test provider (tasty-hunit, tasty-smallcheck etc.) provides a function to turn a test case into a TestTree.

Groups can be created using testGroup.

testGroup :: TestName -> [TestTree] -> TestTreeSource

Create a named group of test cases or other groups

Running tests

defaultMain :: TestTree -> IO ()Source

Parse the command line arguments and run the tests

defaultMainWithIngredients :: [Ingredient] -> TestTree -> IO ()Source

Parse the command line arguments and run the tests using the provided ingredient list

defaultIngredients :: [Ingredient]Source

List of the default ingredients. This is what defaultMain uses.

At the moment it consists of listingTests and consoleTestReporter.

includingOptions :: [OptionDescription] -> IngredientSource

This ingredient doesn't do anything apart from registering additional options.

The option values can be accessed using askOption.

Adjusting and querying options

Normally options are specified on the command line. But you can also have different options for different subtrees in the same tree, using the functions below.

Note that ingredient options (number of threads, hide successes etc.) set in this way will not have any effect. This is for modifying per-test options, such as timeout, number of generated tests etc.

adjustOption :: IsOption v => (v -> v) -> TestTree -> TestTreeSource

Locally adjust the option value for the given test subtree

localOption :: IsOption v => v -> TestTree -> TestTreeSource

Locally set the option value for the given test subtree

askOption :: IsOption v => (v -> TestTree) -> TestTreeSource

Customize the test tree based on the run-time options

Standard options

data Timeout Source

Timeout to be applied to individual tests


Timeout Integer String

String is the original representation of the timeout (such as "0.5m"), so that we can print it back. Integer is the number of microseconds.




:: Integer


-> Timeout 

A shortcut for creating Timeout values


Sometimes several tests need to access the same resource — say, a file or a socket. We want to create or grab the resource before the tests are run, and destroy or release afterwards.



:: IO a

initialize the resource

-> (a -> IO ())

free the resource

-> (IO a -> TestTree)

IO a is an action which returns the acquired resource. Despite it being an IO action, the resource it returns will be acquired only once and shared across all the tests in the tree.

-> TestTree 

Acquire the resource to run this test (sub)tree and release it afterwards