tdd-util

tdd-util is a small test framework for TDD (cf. https://en.wikipedia.org/wiki/Test-driven_development) that integrates three testing libraries, whose modules are all exported under Test.Util.Framework, while providing utilities based on each of these, exported under Test.Util, by wrapping the library test-framework. Getting Started To get started, an example that uses this library is this library's test suite itself and can be found at https://github.com/bairyn/tdd-util/tree/master/testsrc. Each module under src corresponds with a module under testsrc/Test that contains the tests for that module. (For example, this library currently exports two modules in src/Test/Util.hs and src/Test/Util/Framework.hs; their tests are located, respectively, in testsrc/Test/Test/Util.hs and testsrc/Test/Test/Util/Framework.hs; and a module in src/Data/Trie.hs would correspond with a test module in testsrc/Test/Trie.hs). This structure can be conveniently cargo culted from this library, but these conventions are not enforced. Test Modules Conventially, each module in src/X.hs corresponds with a module that contains tests for that module located at testsrc/Test/X.hs. None of these Test modules depend on each other by importing them. For a concrete example of such a test module, see https://github.com/bairyn/tdd-util/blob/master/testsrc/Test/Test/Util.hs. Each test module exports a list of test-framework's TTests (an alias to disambiguate between Test types from different libraries) named tests. This list of tests can either be run individually by importing the test module, and then running defaultMain tests; or be grouped together in the test-suite's Tests module (see below). In the tests themselves, very briefly, testGroup "Brief description of test" […] can be used to construct a single test-framework test (TTest) from a group of other tests, testProperty name prop_foo can be used to construct a TTest from a QuickCheck property, and testCase name $ do … can be used to construct a test from HUnit. See test-framework's documentation for more information about constructing QuickCheck and HUnit properties. Here is a segment of code from https://github.com/bairyn/tdd-util/blob/master/testsrc/Test/Test/Util.hs: Tests.hs Each test module is conventionally grouped into a single test module, at testsrc/Tests.hs (e.g. see https://github.com/bairyn/tdd-util/blob/master/testsrc/Tests.hs), that exports a list of TTests named tests. Interactively, this test module can be loaded in ghci, and the tests can be run as before, with defaultMain tests. These tests can also be specified in the project's cabal file, by invoking defaultMain on tests in an external Main.hs file under testsrc (e.g. see https://github.com/bairyn/tdd-util/blob/master/testsrc/Main.hs). Running this Main.hs will result in the test suite being run, so a test-suite section can be added to the cabal file as it is in https://github.com/bairyn/tdd-util/blob/master/tdd-util.cabal. When a test suite is specified, cabal will recognized it and, when configured to do so, will run it when installing your package, resulting in output that may look like this when it succeeds. This package's Tests.hs: Main.hs Example Main.hs conventially defines a simple program that invokes defaultMain tests from the test group that encapsulates the entire test suite in Tests.hs. Here is this package's Main.hs file: Cabal Configuration Your package's cabal configuration can be updated to point to testsrc/Main.hs/; here is a segment in this package's Cabal file that contains part of the specification for the package's test suite: Note that tdd-util is the only TDD library one needs to depend on, if one only uses QuickCheck, HUnit, and test-framework via Test.Util.Framework; this omission is strictly optional, of course. Test Running Example Here is the output of importing Test.Test.Util inside the testsrc directory and then running tests on my system (note this is not the result of running the entire test suite; to do that, either run Main.hs or run, with defaultMain, the tests exported from Tests.hs rather than Test.Test.Util), without the coloured formatting: