Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Fix ToPrimitive for f64 -> f32 conversion. #180

Merged
merged 1 commit into from
Apr 15, 2016
Merged

Fix ToPrimitive for f64 -> f32 conversion. #180

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
21 changes: 19 additions & 2 deletions traits/src/cast.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -222,9 +222,11 @@ macro_rules! impl_to_primitive_float_to_float {
if size_of::<$SrcT>() <= size_of::<$DstT>() {
Some($slf as $DstT)
} else {
// Make sure the value is in range for the cast.
// NaN and +-inf are cast as they are.
let n = $slf as f64;
let max_value: $SrcT = ::std::$SrcT::MAX;
if -max_value as f64 <= n && n <= max_value as f64 {
let max_value: $DstT = ::std::$DstT::MAX;
if !n.is_finite() || (-max_value as f64 <= n && n <= max_value as f64) {
Some($slf as $DstT)
} else {
None
Expand Down Expand Up @@ -431,3 +433,18 @@ impl_num_cast!(i64, to_i64);
impl_num_cast!(isize, to_isize);
impl_num_cast!(f32, to_f32);
impl_num_cast!(f64, to_f64);


#[test]
fn to_primitive_float() {
use std::f32;
use std::f64;

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()));
}