feat(faker): unique data generation

[System-Glitch]

Refer to issue #76

• Added a unique tag to generate unique data.
  • Call ResetUnique() after generating a dataset to forget all already generated values
• Added tests for the new feature
• Added unique support for Lorem generator as a proposal for the single fake data functions. My implementation is redundant. Any feedback would be appreciated before implementing it to the other single fake data functions.
  • Call SetGenerateUniqueValues(true) to enable unique data generation on single fake data functions
  • Call SetGenerateUniqueValues(false) to disable it
  • Call ResetUnique() to forget all already generated values

This change shouldn't break backwards compatibility.

TODO:

• Update documentation
• Implement unique handling in all single fake data functions

[bxcodec]

Any updates on this PR @System-Glitch

[System-Glitch]

@bxcodec Well I was waiting for feedback on the single fake data functions before continuing. Does this look ok for you? I feel like it's far from optimal.

[System-Glitch]

if generateUniqueValues {
	v, err := generateUnique(PARAGRAPH, func() interface{} {
		return i.paragraph()
	})
	if err != nil {
		panic(err)
	}
	return v.(string)
}

This part is redundant. It has to be there for every single fake data function. Maybe you have an idea to make it better?

I though about another function to factor this.

func singleFakeData(dataType string, fn func() interface{}) interface{} {
	if generateUniqueValues {
		v, err := generateUnique(dataType, fn)
		if err != nil {
			panic(err)
		}
		return v
	}
	return fn()
}

That would shorten a single fake data function to this.

func Word() string {
	i := Lorem{}
	return singleFakeData(WORD, func() interface{} {
		return i.word()
	}).(string)
}

[System-Glitch]

@bxcodec PR is ready to be merged.

[bxcodec]

LGTM

[bxcodec]

Thanks for the PR @System-Glitch 👍