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#![allow(dead_code)]
#[macro_use]
extern crate derive_more;
use std::convert::{TryFrom, TryInto};
// Ensure that the TryFrom macro is hygenic and doesn't break when `Result` has
// been redefined.
type Result = ();
#[derive(Clone, Copy, TryInto)]
#[try_into(owned, ref, ref_mut)]
enum MixedInts {
SmallInt(i32),
NamedBigInt {
int: i64,
},
UnsignedWithIgnoredField(#[try_into(ignore)] bool, i64),
NamedUnsignedWithIgnnoredField {
#[try_into(ignore)]
useless: bool,
x: i64,
},
TwoSmallInts(i32, i32),
NamedBigInts {
x: i64,
y: i64,
},
Unsigned(u32),
NamedUnsigned {
x: u32,
},
Unit,
#[try_into(ignore)]
Unit2,
}
#[test]
fn test_try_into() {
let mut i = MixedInts::SmallInt(42);
assert_eq!(Ok(42i32), i.try_into());
assert_eq!(Ok(&42i32), (&i).try_into());
assert_eq!(Ok(&mut 42i32), (&mut i).try_into());
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(
u32::try_from(i),
Err("Only Unsigned, NamedUnsigned can be converted to u32")
);
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let mut i = MixedInts::NamedBigInt { int: 42 };
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(Ok(42i64), i.try_into());
assert_eq!(Ok(&42i64), (&i).try_into());
assert_eq!(Ok(&mut 42i64), (&mut i).try_into());
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(
u32::try_from(i),
Err("Only Unsigned, NamedUnsigned can be converted to u32")
);
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let mut i = MixedInts::TwoSmallInts(42, 64);
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(Ok((42i32, 64i32)), i.try_into());
assert_eq!(Ok((&42i32, &64i32)), (&i).try_into());
assert_eq!(Ok((&mut 42i32, &mut 64i32)), (&mut i).try_into());
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(
u32::try_from(i),
Err("Only Unsigned, NamedUnsigned can be converted to u32")
);
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let mut i = MixedInts::NamedBigInts { x: 42, y: 64 };
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(Ok((42i64, 64i64)), i.try_into());
assert_eq!(Ok((&42i64, &64i64)), (&i).try_into());
assert_eq!(Ok((&mut 42i64, &mut 64i64)), (&mut i).try_into());
assert_eq!(
u32::try_from(i),
Err("Only Unsigned, NamedUnsigned can be converted to u32")
);
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let mut i = MixedInts::Unsigned(42);
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(Ok(42u32), i.try_into());
assert_eq!(Ok(&42u32), (&i).try_into());
assert_eq!(Ok(&mut 42u32), (&mut i).try_into());
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let mut i = MixedInts::NamedUnsigned { x: 42 };
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(Ok(42u32), i.try_into());
assert_eq!(Ok(&42u32), (&i).try_into());
assert_eq!(Ok(&mut 42u32), (&mut i).try_into());
assert_eq!(<()>::try_from(i), Err("Only Unit can be converted to ()"));
let i = MixedInts::Unit;
assert_eq!(
i32::try_from(i),
Err("Only SmallInt can be converted to i32")
);
assert_eq!(
i64::try_from(i),
Err("Only NamedBigInt, UnsignedWithIgnoredField, NamedUnsignedWithIgnnoredField can be converted to i64")
);
assert_eq!(
<(i32, i32)>::try_from(i),
Err("Only TwoSmallInts can be converted to (i32, i32)")
);
assert_eq!(
<(i64, i64)>::try_from(i),
Err("Only NamedBigInts can be converted to (i64, i64)")
);
assert_eq!(
u32::try_from(i),
Err("Only Unsigned, NamedUnsigned can be converted to u32")
);
assert_eq!(Ok(()), i.try_into());
}
|
