Add the 'Mocha.js' test runner and convert all existing tests to that.
Also, re-structure the current tests into different files for testing the different functions.
Use npm test to call the test suite (after installing devDependencies using npm install -d)
npm install -d
Move all test-related files into separate directory
Add mocha.js test runner to devDependencies
Fixup include paths
Modify test-crop.js for Mocha test runner
Modify test.js for Mocha test runner
Separated test.js into different suites
Add test script (to be called using "npm test") to package.json
Rename 'sample-images' to 'fixtures'
Tests may require all kinds of input data.