Unit testing support with Console/Html/String outputs.

elm-package install project-fuzzball/test 6.0.0


elm-test Build Status

Write tests in Elm!

Getting Started

Let's start with some example code:

test : Test
test =
    describe "The String module"
        [ describe "String.reverse" -- Nest as many descriptions as you like.
            [ test "has no effect on a palindrome" <|
                \() ->
                        palindrome =
                        Expect.equal palindrome (String.reverse palindrome)

            -- Expect.equal is designed to be used in pipeline style, like this.
            , test "reverses a known string" <|
                \() ->
                        |> String.reverse
                        |> Expect.equal "GFEDCBA"

            -- fuzz runs the test 100 times with randomly-generated inputs!
            , fuzz string "restores the original string if you run it again" <|
                \randomlyGeneratedString ->
                        |> String.reverse
                        |> String.reverse
                        |> Expect.equal randomlyGeneratedString

This code includes a few common things:

  • describe to add a description string to a list of tests
  • test to write a unit test
  • Expect to determine if a test should pass or fail
  • fuzz to run a test several times with randomly-generated inputs.

Check out a more complete example or a large real-world test suite for more.

Running tests locally

There are several ways you can run tests locally:

Running tests on CI

Here are some examples of running tests on CI servers: