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When run from `jest --coverage`, produces invalid code

See original GitHub issue

The test repo with the error Jest 19.0.2, babel-plugin-istanbul-4.0.0

The error happens to be related to a particular code. Test is passed ok, but when jest is run with --coverage, a Syntax Error happens. I made a minimal code example in the buggy function:

function buggy(stages, cs) {
    for (let i = 0; i < stages.length; i++) {
        if (cs > i) {
            continue;
        }
        let stage = stages[i];
        if (!stage.complete) {
            when(() => stage.complete, callback);
            break;
        }
    }
    return true;
}

Seems to be a code generation issue.

$ jest --coverage
 FAIL  ./buggy.test.js
  ● Test suite failed to run

    /Users/max/Documents/projects/bugs_demo/buggy.js:16
            } else /* istanbul ignore next */{++cov_2f4l4kc7dh.b[1][1];}};_loop2: for (var i = 0; i < stages.length; i++) {/* istanbul ignore next */var _ret = _loop(i); /* istanbul ignore next */switch (_ret) {case "continue":continue;case "break":break (/* istanbul ignore next */_loop2);}
                                                                                                                                                                                                                                                               ^
    SyntaxError: Unexpected token (

      at transformAndBuildScript (node_modules/jest-runtime/build/transform.js:320:12)
      at Object.<anonymous> (buggy.test.js:1:115)

Ref: https://github.com/facebook/jest/issues/3089