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use anyhow::{bail, Context, Result};
use std::io;
fn f() -> Result<()> {
bail!(io::Error::new(io::ErrorKind::PermissionDenied, "oh no!"));
}
fn g() -> Result<()> {
f().context("f failed")
}
fn h() -> Result<()> {
g().context("g failed")
}
const EXPECTED_ALTDISPLAY_F: &str = "oh no!";
const EXPECTED_ALTDISPLAY_G: &str = "f failed: oh no!";
const EXPECTED_ALTDISPLAY_H: &str = "g failed: f failed: oh no!";
const EXPECTED_DEBUG_F: &str = "oh no!";
const EXPECTED_DEBUG_G: &str = "\
f failed
Caused by:
oh no!\
";
const EXPECTED_DEBUG_H: &str = "\
g failed
Caused by:
0: f failed
1: oh no!\
";
const EXPECTED_ALTDEBUG_F: &str = "\
Custom {
kind: PermissionDenied,
error: \"oh no!\",
}\
";
const EXPECTED_ALTDEBUG_G: &str = "\
Error {
context: \"f failed\",
source: Custom {
kind: PermissionDenied,
error: \"oh no!\",
},
}\
";
const EXPECTED_ALTDEBUG_H: &str = "\
Error {
context: \"g failed\",
source: Error {
context: \"f failed\",
source: Custom {
kind: PermissionDenied,
error: \"oh no!\",
},
},
}\
";
#[test]
fn test_display() {
assert_eq!("g failed", h().unwrap_err().to_string());
}
#[test]
fn test_altdisplay() {
assert_eq!(EXPECTED_ALTDISPLAY_F, format!("{:#}", f().unwrap_err()));
assert_eq!(EXPECTED_ALTDISPLAY_G, format!("{:#}", g().unwrap_err()));
assert_eq!(EXPECTED_ALTDISPLAY_H, format!("{:#}", h().unwrap_err()));
}
#[test]
#[cfg_attr(not(backtrace), ignore)]
fn test_debug() {
assert_eq!(EXPECTED_DEBUG_F, format!("{:?}", f().unwrap_err()));
assert_eq!(EXPECTED_DEBUG_G, format!("{:?}", g().unwrap_err()));
assert_eq!(EXPECTED_DEBUG_H, format!("{:?}", h().unwrap_err()));
}
#[test]
fn test_altdebug() {
assert_eq!(EXPECTED_ALTDEBUG_F, format!("{:#?}", f().unwrap_err()));
assert_eq!(EXPECTED_ALTDEBUG_G, format!("{:#?}", g().unwrap_err()));
assert_eq!(EXPECTED_ALTDEBUG_H, format!("{:#?}", h().unwrap_err()));
}