Run single test with jest.runCLI()

Question

I want to use jest.runCLI() in gulp for executing only a changed test.

How can I do this?

How can I run just one test with jest.runCLI()?

Answer 1

Jest has a CLI option to run only changed files (based on the git repository status). The command line jest --onlyChanged becomes programmatically:

jest.runCLI({'onlyChanged': true}, __dirname, function (success) {...});

Using the terminal, jest uses non-hyphenated options to specified filenames:

• jest test1 runs only test1.js
• jest test1 test2 runs test1.js and test2.js

jest-cli uses optimist to parse options and non-hyphenated option are mapped to the underscore option (_):

• jest.runCLI({'_': ['test1']}, __dirname, function (success) {...}); runs only test1.js
• jest.runCLI({'_': ['test1', 'test2']}, __dirname, function (success) {...}); runs test1.js and test2.js