openethereum/json/src/uint.rs
Lorenzo Manacorda e630f647d1 spec: Validate required divisor fields are not 0 (#7933)
* Add validate_non_zero function

It's used to validate that a Spec's uint field used as a divisor is not zero.

* Add deserialize_with to gas_limit_bound_divisor

Prevents panics due to divide-by-zero on the gas_limit_bound_divisor
field.

* Add deserialize_with to difficulty_bound_divisor

Prevents panics due to divide-by-zero on the difficulty_bound_divisor
field.

* Add validate_optional_non_zero function

Used to validate Option<Uint> divisor fields.

* Use deserialize_with on optional divisor fields.

* Add #[serde(default)] attribute to divisor fields

When using `#[serde(deserialize_with)]`, `#[serde(default)]` must be specified so that missing
fields can be deserialized with the deserializer for `None`.
2018-02-19 10:36:34 +01:00

139 lines
3.6 KiB
Rust

// Copyright 2015-2017 Parity Technologies (UK) Ltd.
// This file is part of Parity.
// Parity is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
// Parity is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
// You should have received a copy of the GNU General Public License
// along with Parity. If not, see <http://www.gnu.org/licenses/>.
//! Lenient uint json deserialization for test json files.
use std::fmt;
use std::str::FromStr;
use serde::{Deserialize, Deserializer};
use serde::de::{Error, Visitor, Unexpected};
use ethereum_types::U256;
/// Lenient uint json deserialization for test json files.
#[derive(Default, Debug, PartialEq, Eq, PartialOrd, Ord, Hash, Clone, Copy)]
pub struct Uint(pub U256);
impl Into<U256> for Uint {
fn into(self) -> U256 {
self.0
}
}
impl Into<u64> for Uint {
fn into(self) -> u64 {
u64::from(self.0)
}
}
impl Into<usize> for Uint {
fn into(self) -> usize {
// TODO: clean it after util conversions refactored.
u64::from(self.0) as usize
}
}
impl Into<u8> for Uint {
fn into(self) -> u8 {
u64::from(self.0) as u8
}
}
impl<'a> Deserialize<'a> for Uint {
fn deserialize<D>(deserializer: D) -> Result<Self, D::Error>
where D: Deserializer<'a> {
deserializer.deserialize_any(UintVisitor)
}
}
struct UintVisitor;
impl<'a> Visitor<'a> for UintVisitor {
type Value = Uint;
fn expecting(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
write!(formatter, "a hex encoded or decimal uint")
}
fn visit_u64<E>(self, value: u64) -> Result<Self::Value, E> where E: Error {
Ok(Uint(U256::from(value)))
}
fn visit_str<E>(self, value: &str) -> Result<Self::Value, E> where E: Error {
let value = match value.len() {
0 => U256::from(0),
2 if value.starts_with("0x") => U256::from(0),
_ if value.starts_with("0x") => U256::from_str(&value[2..]).map_err(|e| {
Error::custom(format!("Invalid hex value {}: {}", value, e).as_str())
})?,
_ => U256::from_dec_str(value).map_err(|e| {
Error::custom(format!("Invalid decimal value {}: {:?}", value, e).as_str())
})?
};
Ok(Uint(value))
}
fn visit_string<E>(self, value: String) -> Result<Self::Value, E> where E: Error {
self.visit_str(value.as_ref())
}
}
pub fn validate_non_zero<'de, D>(d: D) -> Result<Uint, D::Error> where D: Deserializer<'de> {
let value = Uint::deserialize(d)?;
if value == Uint(U256::from(0)) {
return Err(Error::invalid_value(Unexpected::Unsigned(value.into()), &"a non-zero value"))
}
Ok(value)
}
pub fn validate_optional_non_zero<'de, D>(d: D) -> Result<Option<Uint>, D::Error> where D: Deserializer<'de> {
let value: Option<Uint> = Option::deserialize(d)?;
if let Some(value) = value {
if value == Uint(U256::from(0)) {
return Err(Error::invalid_value(Unexpected::Unsigned(value.into()), &"a non-zero value"))
}
}
Ok(value)
}
#[cfg(test)]
mod test {
use serde_json;
use ethereum_types::U256;
use uint::Uint;
#[test]
fn uint_deserialization() {
let s = r#"["0xa", "10", "", "0x", 0]"#;
let deserialized: Vec<Uint> = serde_json::from_str(s).unwrap();
assert_eq!(deserialized, vec![
Uint(U256::from(10)),
Uint(U256::from(10)),
Uint(U256::from(0)),
Uint(U256::from(0)),
Uint(U256::from(0))
]);
}
#[test]
fn uint_into() {
assert_eq!(U256::from(10), Uint(U256::from(10)).into());
}
}