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use anyhow::anyhow;
use std::error::Error as StdError;
use std::fmt::{self, Display};
use std::io;
#[derive(Debug)]
enum TestError {
Io(io::Error),
}
impl Display for TestError {
fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
match self {
TestError::Io(e) => Display::fmt(e, formatter),
}
}
}
impl StdError for TestError {
fn source(&self) -> Option<&(dyn StdError + 'static)> {
match self {
TestError::Io(io) => Some(io),
}
}
}
#[test]
fn test_literal_source() {
let error = anyhow!("oh no!");
assert!(error.source().is_none());
}
#[test]
fn test_variable_source() {
let msg = "oh no!";
let error = anyhow!(msg);
assert!(error.source().is_none());
let msg = msg.to_owned();
let error = anyhow!(msg);
assert!(error.source().is_none());
}
#[test]
fn test_fmt_source() {
let error = anyhow!("{} {}!", "oh", "no");
assert!(error.source().is_none());
}
#[test]
fn test_io_source() {
let io = io::Error::new(io::ErrorKind::Other, "oh no!");
let error = anyhow!(TestError::Io(io));
assert_eq!("oh no!", error.source().unwrap().to_string());
}
#[test]
fn test_anyhow_from_anyhow() {
let error = anyhow!("oh no!").context("context");
let error = anyhow!(error);
assert_eq!("oh no!", error.source().unwrap().to_string());
}