| //! Tests of `num_traits::cast`. |
| |
| #![no_std] |
| |
| #[cfg(feature = "std")] |
| #[macro_use] |
| extern crate std; |
| |
| extern crate num_traits; |
| |
| use num_traits::cast::*; |
| use num_traits::Bounded; |
| |
| use core::{f32, f64}; |
| #[cfg(has_i128)] |
| use core::{i128, u128}; |
| use core::{i16, i32, i64, i8, isize}; |
| use core::{u16, u32, u64, u8, usize}; |
| |
| use core::fmt::Debug; |
| use core::mem; |
| use core::num::Wrapping; |
| |
| #[test] |
| fn to_primitive_float() { |
| let f32_toolarge = 1e39f64; |
| assert_eq!(f32_toolarge.to_f32(), None); |
| assert_eq!((f32::MAX as f64).to_f32(), Some(f32::MAX)); |
| assert_eq!((-f32::MAX as f64).to_f32(), Some(-f32::MAX)); |
| assert_eq!(f64::INFINITY.to_f32(), Some(f32::INFINITY)); |
| assert_eq!((f64::NEG_INFINITY).to_f32(), Some(f32::NEG_INFINITY)); |
| assert!((f64::NAN).to_f32().map_or(false, |f| f.is_nan())); |
| } |
| |
| #[test] |
| fn wrapping_to_primitive() { |
| macro_rules! test_wrapping_to_primitive { |
| ($($t:ty)+) => { |
| $({ |
| let i: $t = 0; |
| let w = Wrapping(i); |
| assert_eq!(i.to_u8(), w.to_u8()); |
| assert_eq!(i.to_u16(), w.to_u16()); |
| assert_eq!(i.to_u32(), w.to_u32()); |
| assert_eq!(i.to_u64(), w.to_u64()); |
| assert_eq!(i.to_usize(), w.to_usize()); |
| assert_eq!(i.to_i8(), w.to_i8()); |
| assert_eq!(i.to_i16(), w.to_i16()); |
| assert_eq!(i.to_i32(), w.to_i32()); |
| assert_eq!(i.to_i64(), w.to_i64()); |
| assert_eq!(i.to_isize(), w.to_isize()); |
| assert_eq!(i.to_f32(), w.to_f32()); |
| assert_eq!(i.to_f64(), w.to_f64()); |
| })+ |
| }; |
| } |
| |
| test_wrapping_to_primitive!(usize u8 u16 u32 u64 isize i8 i16 i32 i64); |
| } |
| |
| #[test] |
| fn wrapping_is_toprimitive() { |
| fn require_toprimitive<T: ToPrimitive>(_: &T) {} |
| require_toprimitive(&Wrapping(42)); |
| } |
| |
| #[test] |
| fn wrapping_is_fromprimitive() { |
| fn require_fromprimitive<T: FromPrimitive>(_: &T) {} |
| require_fromprimitive(&Wrapping(42)); |
| } |
| |
| #[test] |
| fn wrapping_is_numcast() { |
| fn require_numcast<T: NumCast>(_: &T) {} |
| require_numcast(&Wrapping(42)); |
| } |
| |
| #[test] |
| fn as_primitive() { |
| let x: f32 = (1.625f64).as_(); |
| assert_eq!(x, 1.625f32); |
| |
| let x: f32 = (3.14159265358979323846f64).as_(); |
| assert_eq!(x, 3.1415927f32); |
| |
| let x: u8 = (768i16).as_(); |
| assert_eq!(x, 0); |
| } |
| |
| #[test] |
| fn float_to_integer_checks_overflow() { |
| // This will overflow an i32 |
| let source: f64 = 1.0e+123f64; |
| |
| // Expect the overflow to be caught |
| assert_eq!(cast::<f64, i32>(source), None); |
| } |
| |
| #[test] |
| fn cast_to_int_checks_overflow() { |
| let big_f: f64 = 1.0e123; |
| let normal_f: f64 = 1.0; |
| let small_f: f64 = -1.0e123; |
| assert_eq!(None, cast::<f64, isize>(big_f)); |
| assert_eq!(None, cast::<f64, i8>(big_f)); |
| assert_eq!(None, cast::<f64, i16>(big_f)); |
| assert_eq!(None, cast::<f64, i32>(big_f)); |
| assert_eq!(None, cast::<f64, i64>(big_f)); |
| |
| assert_eq!(Some(normal_f as isize), cast::<f64, isize>(normal_f)); |
| assert_eq!(Some(normal_f as i8), cast::<f64, i8>(normal_f)); |
| assert_eq!(Some(normal_f as i16), cast::<f64, i16>(normal_f)); |
| assert_eq!(Some(normal_f as i32), cast::<f64, i32>(normal_f)); |
| assert_eq!(Some(normal_f as i64), cast::<f64, i64>(normal_f)); |
| |
| assert_eq!(None, cast::<f64, isize>(small_f)); |
| assert_eq!(None, cast::<f64, i8>(small_f)); |
| assert_eq!(None, cast::<f64, i16>(small_f)); |
| assert_eq!(None, cast::<f64, i32>(small_f)); |
| assert_eq!(None, cast::<f64, i64>(small_f)); |
| } |
| |
| #[test] |
| fn cast_to_unsigned_int_checks_overflow() { |
| let big_f: f64 = 1.0e123; |
| let normal_f: f64 = 1.0; |
| let small_f: f64 = -1.0e123; |
| assert_eq!(None, cast::<f64, usize>(big_f)); |
| assert_eq!(None, cast::<f64, u8>(big_f)); |
| assert_eq!(None, cast::<f64, u16>(big_f)); |
| assert_eq!(None, cast::<f64, u32>(big_f)); |
| assert_eq!(None, cast::<f64, u64>(big_f)); |
| |
| assert_eq!(Some(normal_f as usize), cast::<f64, usize>(normal_f)); |
| assert_eq!(Some(normal_f as u8), cast::<f64, u8>(normal_f)); |
| assert_eq!(Some(normal_f as u16), cast::<f64, u16>(normal_f)); |
| assert_eq!(Some(normal_f as u32), cast::<f64, u32>(normal_f)); |
| assert_eq!(Some(normal_f as u64), cast::<f64, u64>(normal_f)); |
| |
| assert_eq!(None, cast::<f64, usize>(small_f)); |
| assert_eq!(None, cast::<f64, u8>(small_f)); |
| assert_eq!(None, cast::<f64, u16>(small_f)); |
| assert_eq!(None, cast::<f64, u32>(small_f)); |
| assert_eq!(None, cast::<f64, u64>(small_f)); |
| } |
| |
| #[test] |
| #[cfg(has_i128)] |
| fn cast_to_i128_checks_overflow() { |
| let big_f: f64 = 1.0e123; |
| let normal_f: f64 = 1.0; |
| let small_f: f64 = -1.0e123; |
| assert_eq!(None, cast::<f64, i128>(big_f)); |
| assert_eq!(None, cast::<f64, u128>(big_f)); |
| |
| assert_eq!(Some(normal_f as i128), cast::<f64, i128>(normal_f)); |
| assert_eq!(Some(normal_f as u128), cast::<f64, u128>(normal_f)); |
| |
| assert_eq!(None, cast::<f64, i128>(small_f)); |
| assert_eq!(None, cast::<f64, u128>(small_f)); |
| } |
| |
| #[cfg(feature = "std")] |
| fn dbg(args: ::core::fmt::Arguments) { |
| println!("{}", args); |
| } |
| |
| #[cfg(not(feature = "std"))] |
| fn dbg(_: ::core::fmt::Arguments) {} |
| |
| // Rust 1.8 doesn't handle cfg on macros correctly |
| macro_rules! dbg { ($($tok:tt)*) => { dbg(format_args!($($tok)*)) } } |
| |
| macro_rules! float_test_edge { |
| ($f:ident -> $($t:ident)+) => { $({ |
| dbg!("testing cast edge cases for {} -> {}", stringify!($f), stringify!($t)); |
| |
| let small = if $t::MIN == 0 || mem::size_of::<$t>() < mem::size_of::<$f>() { |
| $t::MIN as $f - 1.0 |
| } else { |
| ($t::MIN as $f).raw_offset(1).floor() |
| }; |
| let fmin = small.raw_offset(-1); |
| dbg!(" testing min {}\n\tvs. {:.0}\n\tand {:.0}", $t::MIN, fmin, small); |
| assert_eq!(Some($t::MIN), cast::<$f, $t>($t::MIN as $f)); |
| assert_eq!(Some($t::MIN), cast::<$f, $t>(fmin)); |
| assert_eq!(None, cast::<$f, $t>(small)); |
| |
| let (max, large) = if mem::size_of::<$t>() < mem::size_of::<$f>() { |
| ($t::MAX, $t::MAX as $f + 1.0) |
| } else { |
| let large = $t::MAX as $f; // rounds up! |
| let max = large.raw_offset(-1) as $t; // the next smallest possible |
| assert_eq!(max.count_ones(), $f::MANTISSA_DIGITS); |
| (max, large) |
| }; |
| let fmax = large.raw_offset(-1); |
| dbg!(" testing max {}\n\tvs. {:.0}\n\tand {:.0}", max, fmax, large); |
| assert_eq!(Some(max), cast::<$f, $t>(max as $f)); |
| assert_eq!(Some(max), cast::<$f, $t>(fmax)); |
| assert_eq!(None, cast::<$f, $t>(large)); |
| |
| dbg!(" testing non-finite values"); |
| assert_eq!(None, cast::<$f, $t>($f::NAN)); |
| assert_eq!(None, cast::<$f, $t>($f::INFINITY)); |
| assert_eq!(None, cast::<$f, $t>($f::NEG_INFINITY)); |
| })+} |
| } |
| |
| trait RawOffset: Sized { |
| type Raw; |
| fn raw_offset(self, offset: Self::Raw) -> Self; |
| } |
| |
| impl RawOffset for f32 { |
| type Raw = i32; |
| fn raw_offset(self, offset: Self::Raw) -> Self { |
| unsafe { |
| let raw: Self::Raw = mem::transmute(self); |
| mem::transmute(raw + offset) |
| } |
| } |
| } |
| |
| impl RawOffset for f64 { |
| type Raw = i64; |
| fn raw_offset(self, offset: Self::Raw) -> Self { |
| unsafe { |
| let raw: Self::Raw = mem::transmute(self); |
| mem::transmute(raw + offset) |
| } |
| } |
| } |
| |
| #[test] |
| fn cast_float_to_int_edge_cases() { |
| float_test_edge!(f32 -> isize i8 i16 i32 i64); |
| float_test_edge!(f32 -> usize u8 u16 u32 u64); |
| float_test_edge!(f64 -> isize i8 i16 i32 i64); |
| float_test_edge!(f64 -> usize u8 u16 u32 u64); |
| } |
| |
| #[test] |
| #[cfg(has_i128)] |
| fn cast_float_to_i128_edge_cases() { |
| float_test_edge!(f32 -> i128 u128); |
| float_test_edge!(f64 -> i128 u128); |
| } |
| |
| macro_rules! int_test_edge { |
| ($f:ident -> { $($t:ident)+ } with $BigS:ident $BigU:ident ) => { $({ |
| fn test_edge() { |
| dbg!("testing cast edge cases for {} -> {}", stringify!($f), stringify!($t)); |
| |
| match ($f::MIN as $BigS).cmp(&($t::MIN as $BigS)) { |
| Greater => { |
| assert_eq!(Some($f::MIN as $t), cast::<$f, $t>($f::MIN)); |
| } |
| Equal => { |
| assert_eq!(Some($t::MIN), cast::<$f, $t>($f::MIN)); |
| } |
| Less => { |
| let min = $t::MIN as $f; |
| assert_eq!(Some($t::MIN), cast::<$f, $t>(min)); |
| assert_eq!(None, cast::<$f, $t>(min - 1)); |
| } |
| } |
| |
| match ($f::MAX as $BigU).cmp(&($t::MAX as $BigU)) { |
| Greater => { |
| let max = $t::MAX as $f; |
| assert_eq!(Some($t::MAX), cast::<$f, $t>(max)); |
| assert_eq!(None, cast::<$f, $t>(max + 1)); |
| } |
| Equal => { |
| assert_eq!(Some($t::MAX), cast::<$f, $t>($f::MAX)); |
| } |
| Less => { |
| assert_eq!(Some($f::MAX as $t), cast::<$f, $t>($f::MAX)); |
| } |
| } |
| } |
| test_edge(); |
| })+} |
| } |
| |
| #[test] |
| fn cast_int_to_int_edge_cases() { |
| use core::cmp::Ordering::*; |
| |
| macro_rules! test_edge { |
| ($( $from:ident )+) => { $({ |
| int_test_edge!($from -> { isize i8 i16 i32 i64 } with i64 u64); |
| int_test_edge!($from -> { usize u8 u16 u32 u64 } with i64 u64); |
| })+} |
| } |
| |
| test_edge!(isize i8 i16 i32 i64); |
| test_edge!(usize u8 u16 u32 u64); |
| } |
| |
| #[test] |
| #[cfg(has_i128)] |
| fn cast_int_to_128_edge_cases() { |
| use core::cmp::Ordering::*; |
| |
| macro_rules! test_edge { |
| ($( $t:ident )+) => { |
| $( |
| int_test_edge!($t -> { i128 u128 } with i128 u128); |
| )+ |
| int_test_edge!(i128 -> { $( $t )+ } with i128 u128); |
| int_test_edge!(u128 -> { $( $t )+ } with i128 u128); |
| } |
| } |
| |
| test_edge!(isize i8 i16 i32 i64 i128); |
| test_edge!(usize u8 u16 u32 u64 u128); |
| } |
| |
| #[test] |
| fn newtype_from_primitive() { |
| #[derive(PartialEq, Debug)] |
| struct New<T>(T); |
| |
| // minimal impl |
| impl<T: FromPrimitive> FromPrimitive for New<T> { |
| fn from_i64(n: i64) -> Option<Self> { |
| T::from_i64(n).map(New) |
| } |
| |
| fn from_u64(n: u64) -> Option<Self> { |
| T::from_u64(n).map(New) |
| } |
| } |
| |
| macro_rules! assert_eq_from { |
| ($( $from:ident )+) => {$( |
| assert_eq!(T::$from(Bounded::min_value()).map(New), |
| New::<T>::$from(Bounded::min_value())); |
| assert_eq!(T::$from(Bounded::max_value()).map(New), |
| New::<T>::$from(Bounded::max_value())); |
| )+} |
| } |
| |
| fn check<T: PartialEq + Debug + FromPrimitive>() { |
| assert_eq_from!(from_i8 from_i16 from_i32 from_i64 from_isize); |
| assert_eq_from!(from_u8 from_u16 from_u32 from_u64 from_usize); |
| assert_eq_from!(from_f32 from_f64); |
| } |
| |
| macro_rules! check { |
| ($( $ty:ty )+) => {$( check::<$ty>(); )+} |
| } |
| check!(i8 i16 i32 i64 isize); |
| check!(u8 u16 u32 u64 usize); |
| } |
| |
| #[test] |
| fn newtype_to_primitive() { |
| #[derive(PartialEq, Debug)] |
| struct New<T>(T); |
| |
| // minimal impl |
| impl<T: ToPrimitive> ToPrimitive for New<T> { |
| fn to_i64(&self) -> Option<i64> { |
| self.0.to_i64() |
| } |
| |
| fn to_u64(&self) -> Option<u64> { |
| self.0.to_u64() |
| } |
| } |
| |
| macro_rules! assert_eq_to { |
| ($( $to:ident )+) => {$( |
| assert_eq!(T::$to(&Bounded::min_value()), |
| New::<T>::$to(&New(Bounded::min_value()))); |
| assert_eq!(T::$to(&Bounded::max_value()), |
| New::<T>::$to(&New(Bounded::max_value()))); |
| )+} |
| } |
| |
| fn check<T: PartialEq + Debug + Bounded + ToPrimitive>() { |
| assert_eq_to!(to_i8 to_i16 to_i32 to_i64 to_isize); |
| assert_eq_to!(to_u8 to_u16 to_u32 to_u64 to_usize); |
| assert_eq_to!(to_f32 to_f64); |
| } |
| |
| macro_rules! check { |
| ($( $ty:ty )+) => {$( check::<$ty>(); )+} |
| } |
| check!(i8 i16 i32 i64 isize); |
| check!(u8 u16 u32 u64 usize); |
| } |
