I have a computed property in a Vue app I'm tasked with creating unit tests with using jest. I've never used jest before and confused if there's a way to test for a returned value I'm injecting using DBeaver. All I'm getting on the jest side of things is undefined from my attempts while seeing the app locally displaying the desired state change when that value is being adding/removing with SQL using DBeaver. Is there a way to unit test this??

For example sake, let's say I have a default config key and a custom config key. I'd like to use the custom config key if it's present and use the default when it's not.

My computed logic is:

customConfigKey () {
  return this.customConfigKey ?? this.defaultConfigKey;
}

I'm confused how to test this when the value for the customConfigKey is being set via DBeaver via a SQL querie.

Here's what I have for the unit test (the only thing I've been able to see a test pass due to obvious shortcomings.

describe('custom config key ', () => {
  it('returns undefined if configKey does not exist', () => {
    expect(wrapper.vm.CustomConfigKey).toBe(undefined); // value_returned
  });
});