Exercism Java test runner

An Exercism test runner automatically verifies if a submission passes all the tests.

This repository contains the Java test runner, which implements the V3 spec of the test runner interface.

This test runner uses CRaC (Coordinated Restore at Checkpoint) to speed up execution. The build logic is implemented and documented in bin/build-crac-checkpoint-image.sh. If you change this logic you might also have to adjust the GitHub deploy action.

Run the test runner

To run the tests of an arbitrary exercise, do the following:

1. Open a terminal in the project's root
2. Run ./bin/run.sh <exercise-slug> <solution-dir> <output-dir>

Once the test runner has finished, its results will be written to <output-dir>/results.json.

Run the test runner on an exercise using Docker

This script is provided for testing purposes, as it mimics how test runners run in Exercism's production environment.

To run the tests of an arbitrary exercise using the Docker image, do the following:

1. Open a terminal in the project's root
2. Run ./bin/run-in-docker.sh <exercise-slug> <solution-dir> <output-dir>

Once the test runner has finished, its results will be written to <output-dir>/results.json.

Run the tests

To run the tests to verify the behavior of the test runner, do the following:

1. Open a terminal in the project's root
2. Run ./bin/run-tests.sh

These are golden tests that compare the results.json generated by running the current state of the code against the "known good" tests/<test-name>/expected_results.json. All files created during the test run itself are discarded.

When you've made modifications to the code that will result in a new "golden" state, you'll need to generate and commit a new tests/<test-name>/expected_results.json file.

Run the tests using Docker

This script is provided for testing purposes, as it mimics how test runners run in Exercism's production environment.

To run the tests to verify the behavior of the test runner using the Docker image, do the following:

1. Open a terminal in the project's root
2. Run ./bin/run-tests-in-docker.sh

These are golden tests that compare the results.json generated by running the current state of the code against the "known good" tests/<test-name>/expected_results.json. All files created during the test run itself are discarded.

When you've made modifications to the code that will result in a new "golden" state, you'll need to generate and commit a new tests/<test-name>/expected_results.json file.