Crate serde_test

This crate provides a convenient concise way to write unit tests for implementations of Serialize and Deserialize.

The Serialize impl for a value can be characterized by the sequence of Serializer calls that are made in the course of serializing the value, so serde_test provides a Token abstraction which corresponds roughly to Serializer method calls. There is an assert_ser_tokens function to test that a value serializes to a particular sequence of method calls, an assert_de_tokens function to test that a value can be deserialized from a particular sequence of method calls, and an assert_tokens function to test both directions. There are also functions to test expected failure conditions.

Here is an example from the linked-hash-map crate.

use linked_hash_map::LinkedHashMap;
use serde_test::{assert_tokens, Token};

#[test]
fn test_ser_de_empty() {
    let map = LinkedHashMap::<char, u32>::new();

    assert_tokens(
        &map,
        &[
            Token::Map { len: Some(0) },
            Token::MapEnd,
        ],
    );
}

#[test]
fn test_ser_de() {
    let mut map = LinkedHashMap::new();
    map.insert('b', 20);
    map.insert('a', 10);
    map.insert('c', 30);

    assert_tokens(
        &map,
        &[
            Token::Map { len: Some(3) },
            Token::Char('b'),
            Token::I32(20),
            Token::Char('a'),
            Token::I32(10),
            Token::Char('c'),
            Token::I32(30),
            Token::MapEnd,
        ],
    );
}

Structs

Compact

Readable

Enums

Token

Traits

Configure

Trait to determine whether a value is represented in human-readable or compact form.

Functions

assert_de_tokens

Asserts that the given tokens deserialize into value.

assert_de_tokens_error

Asserts that the given tokens yield error when deserializing.

assert_ser_tokens

Asserts that value serializes to the given tokens.

assert_ser_tokens_error

Asserts that value serializes to the given tokens, and then yields error.

assert_tokens

Runs both assert_ser_tokens and assert_de_tokens.