Running Jest

run npm test (alias for npm run test, also npm t works) this will start Jest, which will scan the project directories to find test files

in our case it will find no files (there are none)

➜  jest-101 npm test
No tests found, exiting with code 1

note: files are searched by specific regexes note: node_modules is skipped by default

create an empty file named test.js in the project root

run again npm test

> jest-101@0.0.1 test /Users/jaga/coding/jest-101
> jest

 FAIL  ./test.js
  ● Test suite failed to run

    Your test suite must contain at least one test.

      at node_modules/@jest/core/build/TestScheduler.js:242:24

Test Suites: 1 failed, 1 total
Tests:       0 total
Snapshots:   0 total
Time:        1.354s
Ran all test suites.
npm ERR! Test failed.  See above for more details.

this time Jest finds the file test.js but the command fails with the error Your test suite must contain at least one test.

Author: Jaga Santagostino