test(LocationsCommand): add inital unit tests

[john-u]

Types of Changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)
• I have read the CONTRIBUTING document
• My code follows the code style of this project (lerna run lint produces no warnings/errors)
• Any required documentation has been added
• I have added tests to cover my changes

[john-u]

This seems required with Typescript in order to use anything useful in the jest mock API.

[rossiam]

You could probably do something like this:

const outputListingMock = jest.fn()
jest.mock('@smarthings/cli-lib', () => {
...
  return {
    ...originalLib,
    outputListing: outputListingMock,
  }
})

And then use outputListingMock instead.

[john-u]

I forgot that I tried that first and ran into this issue. It may be a temporary bug.