The tools.test framework

Factor's built-in testing framework, rather like Factor itself, marries simplicity with unbridled power.

{ 1 } [ 1 ]             unit-test
{   } [ "Hello" print ] unit-test ! print doesn't leave anything on the stack
{ 3 } [ 1 2 + ]         unit-test

Assuming you've learned a little Factor by now, you will see that the unit-test word (which is actually a special syntax element) takes an array of how the stack should look after running a given quotation.

Word definitions should be concise and simplified. They should not be more than 5 or 10 lines long in most cases, and their inputs and outputs should be simple and clearly understandable. Importantly, a given word should do one thing and do it well.

Words written in this way will implicitly be easily unit-testable.

Unit tests (usually a bunch of assertions like above) go in a file called vocab-name-tests.factor beside your implementation vocab-name.factor. This file is already created for you by Exercism, but would normally need to be created by hand, or by "exercise" scaffold-tests.

Get the tools.test wrapper library for Exercism, and put its exercism subfolder inside Factor's work folder, such that testing.factor is located at resource:work/exercism/testing/testing.factor.

When the current directory is your exercism/factor exercises folder:

  • Run a vocabulary's tests from the listener with USE: exercism.testing "exercise-name" run-exercism-test, or from the command-line with factor -run=exercism.testing exercise-name.
  • Run all tests for all exercises with USE: exercism.testing run-all-exercism-tests or from the command-line with factor -run=exercism.testing run-all.

For more information, see the Factor documentation on Unit testing, and exercism.testing's documentation with "exercism.testing" help.

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