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use std::{error::Error, fmt};
#[derive(Debug, PartialEq)]
pub enum AttributeError {
InvalidFormat,
InvalidType,
MissingField {
name: String,
},
}
impl fmt::Display for AttributeError {
fn fmt(
&self,
f: &mut fmt::Formatter<'_>,
) -> fmt::Result {
match self {
AttributeError::InvalidFormat => write!(f, "Invalid format"),
AttributeError::InvalidType => write!(f, "Invalid type"),
AttributeError::MissingField { name } => write!(f, "Missing field {}", name),
}
}
}
impl Error for AttributeError {}
#[cfg(test)]
mod tests {
use super::AttributeError;
use std::error::Error;
#[test]
fn attribute_error_impl_std_error() {
fn test(_: impl Error) {}
test(AttributeError::InvalidFormat)
}
#[test]
fn invalid_format_displays() {
assert_eq!(
"Invalid format",
format!("{}", AttributeError::InvalidFormat)
)
}
#[test]
fn invalid_type_displays() {
assert_eq!("Invalid type", format!("{}", AttributeError::InvalidType))
}
#[test]
fn missing_field_displays() {
assert_eq!(
"Missing field foo",
format!("{}", AttributeError::MissingField { name: "foo".into() })
)
}
}