dtolnay/path-to-error

Find out path at which a deserialization error occurred

Rust

426

179 commits

updated Jun 24, 2026

See the code

README

Serde path to error

github crates.io docs.rs build status

Find out the path at which a deserialization error occurred. This crate provides a wrapper that works with any existing Serde Deserializer and exposes the chain of field names leading to the error.

[dependencies]
serde = "1.0"
serde_path_to_error = "0.1"
use serde::Deserialize;
use std::collections::BTreeMap as Map;

#[derive(Deserialize)]
struct Package {
    name: String,
    dependencies: Map<String, Dependency>,
}

#[derive(Deserialize)]
struct Dependency {
    version: String,
}

fn main() {
    let j = r#"{
        "name": "demo",
        "dependencies": {
            "serde": {
                "version": 1
            }
        }
    }"#;

    // Some Deserializer.
    let jd = &mut serde_json::Deserializer::from_str(j);

    let result: Result<Package, _> = serde_path_to_error::deserialize(jd);
    match result {
        Ok(_) => panic!("expected a type error"),
        Err(err) => {
            let path = err.path().to_string();
            assert_eq!(path, "dependencies.serde.version");
        }
    }
}

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Contributors

dtolnay

171 commits

swlynch99

3 commits

noib3

1 commits

RReverser

1 commits

dtolnay/path-to-error

Find out path at which a deserialization error occurred

Rust

426

179 commits

updated Jun 24, 2026

See the code

README

Serde path to error

github crates.io docs.rs build status

Find out the path at which a deserialization error occurred. This crate provides a wrapper that works with any existing Serde Deserializer and exposes the chain of field names leading to the error.

[dependencies]
serde = "1.0"
serde_path_to_error = "0.1"
use serde::Deserialize;
use std::collections::BTreeMap as Map;

#[derive(Deserialize)]
struct Package {
    name: String,
    dependencies: Map<String, Dependency>,
}

#[derive(Deserialize)]
struct Dependency {
    version: String,
}

fn main() {
    let j = r#"{
        "name": "demo",
        "dependencies": {
            "serde": {
                "version": 1
            }
        }
    }"#;

    // Some Deserializer.
    let jd = &mut serde_json::Deserializer::from_str(j);

    let result: Result<Package, _> = serde_path_to_error::deserialize(jd);
    match result {
        Ok(_) => panic!("expected a type error"),
        Err(err) => {
            let path = err.path().to_string();
            assert_eq!(path, "dependencies.serde.version");
        }
    }
}

License

Licensed under either of Apache License, Version 2.0 or MIT license at your option.
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in this crate by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.

Contributors

dtolnay

171 commits

swlynch99

3 commits

noib3

1 commits

RReverser

1 commits

Languages

Rust

100.0%