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// Written by without boats originally
use derive_more::Display;
#[derive(Display)]
#[display("An error has occurred.")]
struct UnitError;
#[test]
fn unit_struct() {
let s = UnitError.to_string();
assert_eq!(s, "An error has occurred.");
}
#[derive(Display)]
#[display("Error code: {}", code)]
struct RecordError {
code: u32,
}
#[test]
fn record_struct() {
let s = RecordError { code: 0 }.to_string();
assert_eq!(s, "Error code: 0");
}
#[derive(Display)]
#[display("Error code: {}", _0)]
struct TupleError(i32);
#[test]
fn tuple_struct() {
let s = TupleError(2).to_string();
assert_eq!(s, "Error code: 2");
}
#[derive(Display)]
enum EnumError {
#[display("Error code: {}", code)]
StructVariant { code: i32 },
#[display("Error: {}", _0)]
TupleVariant(&'static str),
#[display("An error has occurred.")]
UnitVariant,
}
#[test]
fn enum_error() {
let s = EnumError::StructVariant { code: 2 }.to_string();
assert_eq!(s, "Error code: 2");
let s = EnumError::TupleVariant("foobar").to_string();
assert_eq!(s, "Error: foobar");
let s = EnumError::UnitVariant.to_string();
assert_eq!(s, "An error has occurred.");
}