use anyhow::{anyhow, Chain, Error}; fn error() -> Error { anyhow!({ 0 }).context(1).context(2).context(3) } #[test] fn test_iter() { let e = error(); let mut chain = e.chain(); assert_eq!("3", chain.next().unwrap().to_string()); assert_eq!("2", chain.next().unwrap().to_string()); assert_eq!("1", chain.next().unwrap().to_string()); assert_eq!("0", chain.next().unwrap().to_string()); assert!(chain.next().is_none()); assert!(chain.next_back().is_none()); } #[test] fn test_rev() { let e = error(); let mut chain = e.chain().rev(); assert_eq!("0", chain.next().unwrap().to_string()); assert_eq!("1", chain.next().unwrap().to_string()); assert_eq!("2", chain.next().unwrap().to_string()); assert_eq!("3", chain.next().unwrap().to_string()); assert!(chain.next().is_none()); assert!(chain.next_back().is_none()); } #[test] fn test_len() { let e = error(); let mut chain = e.chain(); assert_eq!(4, chain.len()); assert_eq!((4, Some(4)), chain.size_hint()); assert_eq!("3", chain.next().unwrap().to_string()); assert_eq!(3, chain.len()); assert_eq!((3, Some(3)), chain.size_hint()); assert_eq!("0", chain.next_back().unwrap().to_string()); assert_eq!(2, chain.len()); assert_eq!((2, Some(2)), chain.size_hint()); assert_eq!("2", chain.next().unwrap().to_string()); assert_eq!(1, chain.len()); assert_eq!((1, Some(1)), chain.size_hint()); assert_eq!("1", chain.next_back().unwrap().to_string()); assert_eq!(0, chain.len()); assert_eq!((0, Some(0)), chain.size_hint()); assert!(chain.next().is_none()); } #[test] fn test_default() { let mut c = Chain::default(); assert!(c.next().is_none()); } #[test] fn test_clone() { let e = error(); let mut chain = e.chain().clone(); assert_eq!("3", chain.next().unwrap().to_string()); assert_eq!("2", chain.next().unwrap().to_string()); assert_eq!("1", chain.next().unwrap().to_string()); assert_eq!("0", chain.next().unwrap().to_string()); assert!(chain.next().is_none()); assert!(chain.next_back().is_none()); }