Error: ReferenceError: Can't find variable: exports

While running, the following error comes

```
Error: ReferenceError: Can't find variable: exports
at global code in file:///e:/repos/****/src/****/unittests/spec/app.js (line 4)
While Running:E:\repos\****\src\****\UnitTests\spec\app.ts
```

Any help would be appreciated