Jest No Tests found

Question

running docker mhart/alpine-node:8 on macOS with

nodejs (6.10.3-r0) (18/18) yarn 0.24.6 jest 20.0.4

I have a __tests__/index.test.js file however, when running the code

node_modules/.bin/jest --watchAll I get the below output

No tests found
In /usr/src/app
5 files checked.
testMatch: /__tests__//*.js?(x),**/?(*.)(spec|test).js?(x) - 1 match
testPathIgnorePatterns: /node_modules/,/src,src - 0 matches
Pattern: "" - 0 matches

I've re-installed the package numbers times but to no avail.

Answer 1

Your output says that testMatch had 1 match, which may be your __tests__/index.test.js file. It seems that your testPathIgnorePatterns is causing that test suite to be ignored. No tests found In /usr/src/app says that Jest is looking for tests in /usr/src/app, and testPathIgnorePatterns: /node_modules/,/src,src says that Jest is ignoring files in /src directories.

Either point Jest to look at the location of your __tests__/index.test.js file if it is outside the /src directory, or stop testPathIgnorePatterns from ignoring the /src directory.

Answer 2

If you have file structure such as the following

myFolder │   myFile1.js │   myFile2.js │   ... │    └───__tests__         myFile1.spec.js         myFile2.spec.js         ... 

then you need to have in jest.config.js the following pattern for testMatch property:

testMatch: ['**/__tests__/*.js?(x)'], 

The simple example of jest.config.js:

const jestConfig = {   verbose: true,   testURL: "http://localhost/",   'transform': {     '^.+\\.jsx?$': 'babel-jest',   },   testMatch: ['**/__tests__/*.js?(x)'], }  module.exports = jestConfig