comparable 0.5.6

A library for comparing data structures in Rust, oriented toward testing
Documentation 
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// use serde;

use crate::types::{Changed, Comparable};

#[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
#[derive(PartialEq, Debug)]
pub enum OptionChange<Desc, Change> {
	BothSome(Change),
	Different(Desc, Desc),
}

impl<T: Comparable> Comparable for Option<T> {
	type Desc = Option<T::Desc>;

	fn describe(&self) -> Self::Desc {
		self.as_ref().map(|x| x.describe())
	}

	type Change = OptionChange<Self::Desc, T::Change>;

	fn comparison(&self, other: &Self) -> Changed<Self::Change> {
		match (self, other) {
			(None, None) => Changed::Unchanged,
			(Some(x), Some(y)) => x.comparison(y).map(OptionChange::BothSome),
			(_, _) => Changed::Changed(OptionChange::Different(self.describe(), other.describe())),
		}
	}
}