structdiff
A lightweight, zero-dependency struct diffing library which allows changed fields to be collected and applied. Derive Difference
on a struct, then use the StructDiff
trait to make and apply diffs.
Example:
use structdiff::{Difference, StructDiff};
#[derive(Debug, PartialEq, Clone, Difference)]
struct Example {
field1: f64,
#[difference(skip)]
field2: Vec<i32>,
field3: String,
}
let first = Example {
field1: 0.0,
field2: Vec::new(),
field3: String::from("Hello Diff"),
};
let second = Example {
field1: 3.14,
field2: vec![1],
field3: String::from("Hello Diff"),
};
let diffs = first.diff(&second);
// diffs is now a Vec of differences, with length
// equal to number of changed/unskipped fields
assert_eq!(diffs.len(), 1);
let diffed = first.apply(diffs);
// diffed is now equal to second, except for skipped field
assert_eq!(diffed.field1, second.field1);
assert_eq!(diffed.field3, second.field3);
assert_ne!(diffed, second);
For more examples take a look at integration tests
Derive macro attributes
#[difference(skip)]
- Do not consider this field when creating a diff#[difference(recurse)]
- Generate a StructDiff for this field when creating a diff#[difference(collection_strategy = "{}")
unordered_hash
- Generates a changeset for collections of items which implementHash + Eq
, rather than cloning the entire list. (currently works forVec
,BTreeSet
,LinkedList
, andHashSet
)
Optional features
- [
nanoserde
,serde
] - Serialization ofDifference
derived associated types
Development status
This is being actively worked on (especially on collections strategies). PRs will be accepted for either more tests or functionality.