2 unstable releases
0.2.0 | Aug 29, 2022 |
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0.1.0 | Aug 5, 2022 |
#282 in #variant
5,100 downloads per month
Used in 2 crates
(via random_variant)
10KB
182 lines
RandomVariant
Trait that returns a random variant of the given type, if you are creating a new type to limit some values, instead of deriving the RandomVariant, implement it manually to ensure only correct values are created Unless you also want to try the Result type Useful for hunting down unwraps or other assumptions in your code, The benefit over the crate EveryVariant is that this can be limited to A much smaller set to test, where generting every variant quickly can grow to unmanageable testing sets
Example
use serde::Serialize;
use std::net::IpAddr;
#[derive(RandomVariant, Serialize)]
enum Message {
Log(String),
ErrorCode(u32),
/// This tuple will fail to serialize if flattened in serde
Rebooting,
}
#[derive(RandomVariant, Serialize)]
struct LoggedMessage {
/// Fail to serialize, since flatteing enums is not supported
#[serde(flatten)]
t: Message,
add: IpAddr,
}
let mut rng = crate::rand::thread_rng();
/// This allows us to limit the testing set to trying 100 randomized structs
for _i in 0..100 {
let v = LoggedMessage::random_variant(&mut rng);
serde_json::to_string(&v).unwrap();
}
lib.rs
:
Proc macros that can help with generating implements of the EveryVariant trait for structs and enums
Dependencies
~1.5MB
~38K SLoC