Answer:
The type of figurative language used in the sentence is: parallelism.
Explanation:
We usually study parallelism as the consistent use of certain structures inside a sentence. But, as a matter of fact, parallelism is also a figurative language. It is still connected to the repetition of grammatical structures, and it usually helps give the idea a certain flow or rhythm.
In the sentence we are analyzing here, the repetition takes place in two clauses. That is, the second cause repeats the structure of the first one, which is something like:
superlative + noun + verb to be + too + adjective + for him
The longest days were too short for him
The shortest nights (omitted) too long for him
As we can see, the author did not think it necessary to repeat the verb, since it could be easily inferred. But the rest of the structure is exactly the same, creating parallelism.
