'use strict' declaration doesn't seem to do anything

[awei01]

The 'use strict' declaration in scripts doesn't seem to have any effect in files or in test files.

module file:

\\ foo.js
(function() {
'use strict';

foo = 'foo value';

module.exports = foo;
}());

and test file:

\\ __tests__\foo-test.js
(function() {
'use strict';

jest.dontMock('../foo.js');

    describe('testing use strict', function() {
         it('should throw some sort of error', function() {

              bar = 'bar value';
              console.log(bar);
              console.log(require('../foo'));
         });
    });

}());

running npm test yields:

Using Jest CLI v0.1.15
Found 1 matching tests...
 PASS  __tests__/foo-test.js (0.03s)
bar value
foo value

[ghost]

Thank you for reporting this issue and appreciate your patience. We've notified the core team for an update on this issue. We're looking for a response within the next 30 days or the issue may be closed.

[cpojer]

Let me know if this is still an issue. It should definitely work as expected in node 4.

[github-actions]

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