Error: Please run node with the --harmony flag!

[moroshko]

I get the following error when running gulp test:

Error: Please run node with the --harmony flag!

Here is my gulp task:

gulp.task('test', function() {
  return gulp.src('src/**/__tests__').pipe(jest({
    rootDir: 'src',
    scriptPreprocessor: '../node_modules/6to5-jest',
    unmockedModulePathPatterns: [ 'react' ]
  }));
});

To reproduce: https://github.com/SEEK-Jobs/react-playground

Note that npm test works properly (test is failing as expected), but gulp test fails with the error above. Both npm test and gulp test have the same config object:

{
  rootDir: 'src',
  scriptPreprocessor: '../node_modules/6to5-jest',
  unmockedModulePathPatterns: [ 'react' ]
}

What am I doing wrong?

[Dakuan]

I think this is a gulp issue, see if https://github.com/gulpjs/gulp/issues/66 helps you

[mik01aj]

I don't think this is a Gulp problem. Imho it's either gulp-jest or jest itself. Look at this:

(I didn't change anything in the editor between these commands, so it looks like a really weird bug that happens only when there is just one test file.)

P.S. Here's the relevant part from my gulpfile - nothing special here.

gulp.task('jest', function () {
    return gulp.src('__tests__').pipe($.jest());
});    

[Dakuan]

Have you seen this fix? http://stackoverflow.com/questions/28315796/why-gulp-jest-is-failing-with-please-run-node-with-the-harmony-flag

[mik01aj]

Works great, thanks! But it would be nice to find the original cause of this, anyway :)

[Dakuan]

Indeed - I'm not convinced that the issue is in gulp-jest.

Do you mind if I close this? @mik01aj @moroshko

[mik01aj]

Yes. I suppose it's a bug in jest-cli and I will report it there.

[Dakuan]

I've shipped an update that includes the latest jest-cli which should resolve this for you. Let me know how you get on!

[binarykitchen]

Still having the same issue, even with your latest version:

Error: Please run node with the --harmony flag! jest requires WeakMap which is only available with the --harmony flag in node < v0.12

[joshuacalloway]

I'm seeing this error too. tried adding this to my gulpfile require('harmonize')();

This works fine with my "grunt jest"

[ieugen]

+1, please add to official docs/npm page

[moimikey]

+1 for require('harmonize')(). not a blocker at all with it, but until they update the npm package with their latest patch, you'll lose your stdout colors =/

[screendriver]

+1 for require('harmonize')()

[binarykitchen]

Since nothing happened, I took the liberty to fork it and make it compatible for the latest iojs: https://www.npmjs.com/package/gulp-jest-iojs

[alansouzati]

Is this still an issue? I'm planning to maintain this library now. let me know if the latest version presents any issues.

[alansouzati]

Closing this issue as there is no activity on it.