Ability to mix longest buffer

[Jokab]

Hey, I implemented the feature I requested myself since I figured you were busy. I added tests to make sure it works too. I decided to use a boolean parameter to decide whether to mix or not, added docs too.

[dy]

@Jokab thank you for the PR! I am not sure though the API needs that sort of complication. Why don't you just compare which buffer is longer and mix shorter one into longer one?

[Jokab]

@dfcreative I believe what you are suggesting does not work when there is an offset involved.

If, for example, you have two buffers A and B, of length 4 and 3 respectively, and an offset of 2. What happens currently is that B[0] is mixed at A[2], B[1] is mixed at A[3], and then the mixing loop stops because i < bufferA.length is violated in the code.

As you can see, B is indeed shorter than A, but it still doesn't behave as I would expect it to. The expected behavior, according to me, would be that B[2] is put at A[5], which would indeed extend A by one element. This is the functionality that my PR extends.

[dy]

@Jokab oh, I see, makes sense.
But that is just making padding before mixing, right? Isn't explicit code better than mysterious true argument?

//short & mysterious
a = u.mix(a, b, .5, offset, true)

//long & explicit
a = u.pad(a, Math.max(a.length, b.length) + offset)
u.mix(a, b, .5, offset)

Also in your PR mix now behaves mutable/immutable depending on the longest argument: in first case it modifies a, in second case it returns a new buffer, which may be confusing. With pad we make sure returned buffer is a new one.

Also, this argument is not treated properly (yet).

mix(a, b, true)
mix(a, b, .5, true)
mix(a, b, .5, offset, true)

As a possible solution, I would think on detecting longest by comparing available lengths rather than a separate argument, and forcing immutable result (which is not always desirable though).

[Jokab]

@dfcreative Yeah, I suppose you are right that works too. (Though, you need to do u.pad(a, Math.max(a.length, b.length+offset))) It all depends on how you want to design the API, which of course you decide. My opinion is that my PR is more intuitive (with your suggestions applied), but in the end it's your decision of course.