Error: Failed to get mock metadata on npm test: Why this happen?

[joowh85]

When I try

npm test

always fail with the errors.
What should I do?

My OS is Windows 10.

> eslint src && jest

Using Jest CLI v0.9.0, jasmine2, babel-jest
 FAIL  components\App\__tests__\App-test.js
● Runtime Error
Error: Failed to get mock metadata: C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\core-js\library\modules\_global.js

See: http://facebook.github.io/jest/docs/manual-mocks.html#content
    at Loader._generateMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:355:15)
    at Loader.requireMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:215:45)
    at Loader.requireModuleOrMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:226:19)
    at Object.<anonymous> (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\core-js\library\modules\_shared.js:1:133)
    at Loader._execModule (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:310:17)
    at Loader.requireModule (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:155:14)
    at Loader._generateMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:347:34)
    at Loader.requireMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:215:45)
    at Loader.requireModuleOrMock (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\jest-cli\src\HasteModuleLoader\HasteModuleLoader.js:226:19)
    at Object.<anonymous> (C:\Users\sangw\Documents\Work\jimiarts-web\node_modules\core-js\library\modules\_shared-key.js:1:133)
npm ERR! Test failed.  See above for more details.

[koistya]

I'm unable to reproduce it in the latest version of RSK, on Windows. Have you altered the test, or it matches to the one from this repo? See jestjs/jest#678.

[Stupidism]

Got this error, too.
Ubuntu 14, node 5.6.0.
I got this error in my project first(node 4, npm 3).
Then I reproduce it by following your start guide, git clone ... and npm install with node 5.6.0

Using Jest CLI v0.9.2, jasmine2, babel-jest
 FAIL  components/App/__tests__/App-test.js
● Runtime Error

Error: Failed to get mock metadata: /home/stupid/Desktop/MyApp/node_modules/core-js/library/modules/_global.js

See: http://facebook.github.io/jest/docs/manual-mocks.html#content
    at Object.<anonymous> (/home/stupid/Desktop/MyApp/node_modules/core-js/library/modules/_shared.js:1:133)
    at Object.<anonymous> (/home/stupid/Desktop/MyApp/node_modules/core-js/library/modules/_shared-key.js:1:133)
npm ERR! Test failed.  See above for more details.

[Stupidism]

This only works for me, by far!!!

Finally, I find a solution, although I can't figure out why.

Just delete the whole project and clone from your own repo, not clone a singile-branch from react-starter-kit as the start-guide said. npm test should work.

Of cource, normal process is

• Do as start-guide said.
• Push to your own repo origin master.
• Delete the whole project.
• Clone from your own repo and npm install
• Run npm test

Only remove node_modules and renpm install doesn't do the trick. Maybe something wrong with git itself.

[JeffreyATW]

I'm having the same issue. I even tried changing my App.js file back to the original one here, and I tried re-cloning my repo, but nothing's working.

[Bogdaan]

@stupidisum ) sory, but this is not solution
@JeffreyATW install dev dependency:

npm install --dev

[JeffreyATW]

That didn't do anything. My version of npm says that --dev is deprecated, and I'm pretty sure it installs devDependencies automatically.

Node: 5.9.0, npm: 3.7.3

[JeffreyATW]

Update: I tried updating jest-cli to 0.9.3, which supposedly contains some related fixes, but it didn't fix anything.

[JeffreyATW]

Adding core-js to unmockedModulePathPatterns in package.json results in a separate (possibly unrelated) message:

 FAIL  components/App/__tests__/App-test.js
● Runtime Error
TypeError: Cannot read property 'displayName' of undefined
    at getDisplayName (eval at runSourceText ([...]/node_modules/jest-cli/src/environments/JSDOMEnvironment.js:37:3), <anonymous>:53:26)

[JeffreyATW]

Yep, it looks like that other problem is mine. I'll send a PR to include "core-js" to unmockedModulePathPatterns.

[everdimension]

Same problem on mac.

Unmocking core-js makes the test script throw another error:

● Runtime Error
TypeError: (0 , _useQueries2.default)(...) is not a function
    at Object.<anonymous> (/Users/rnd/web/react-project/src/core/Location.js:14:175)
    at Object.<anonymous> (/Users/rnd/web/react-project/src/components/Link/Link.js:11:41)
    at Object.<anonymous> (/Users/rnd/web/react-project/src/components/Header/Header.js:13:37)
    at Object.<anonymous> (/Users/rnd/web/react-project/src/components/App/App.js:13:39)
    at Object.<anonymous> (/Users/rnd/web/react-project/src/components/App/__tests__/App-test.js:5:36)

[ulani]

@joowh85 thank you very much for crating this issue! Unfortunately, we have close it due to inactivity. Feel free to re-open it or join our Discord channel for discussion.

NOTE: The main branch has been updated with React Starter Kit v2, using JAM-style architecture.