Naive bayes computation of denominator

I'm wondering about the denominator in this computation :

P(Banana|Long, Sweet and Yellow)
P(Long|Banana) * P(Sweet|Banana) * P(Yellow|Banana) * P(banana)
= _______________________________________________________________
P(Long) * P(Sweet) * P(Yellow)


Which is from this post

I don't know that it is valid to convert

P(long, sweet, yellow)


to

P(long)P(sweet)P(yellow)


The reason that I'm confused is that we have conditional independence, rather than complete independence.

Or is this valid here?

edit - text example

It isn't correct exactly for the reason you realized. The evidence calculation should be: $$P(L,S,Y)=\sum_{B'\in \{Banana,Orange,Other\}} P(L|B')P(S|B')P(Y|B')P(B')$$