diff options
| -rw-r--r-- | library/core/src/char/methods.rs | 24 | ||||
| -rw-r--r-- | library/core/src/lib.rs | 1 | ||||
| -rw-r--r-- | library/core/tests/char.rs | 12 |
3 files changed, 21 insertions, 16 deletions
diff --git a/library/core/src/char/methods.rs b/library/core/src/char/methods.rs index b3e1becf570..7f7a1c21e4a 100644 --- a/library/core/src/char/methods.rs +++ b/library/core/src/char/methods.rs @@ -1,6 +1,5 @@ //! impl char {} -use crate::intrinsics::likely; use crate::slice; use crate::str::from_utf8_unchecked_mut; use crate::unicode::printable::is_printable; @@ -332,21 +331,16 @@ impl char { #[inline] pub fn to_digit(self, radix: u32) -> Option<u32> { assert!(radix <= 36, "to_digit: radix is too high (maximum 36)"); - // the code is split up here to improve execution speed for cases where - // the `radix` is constant and 10 or smaller - let val = if likely(radix <= 10) { - // If not a digit, a number greater than radix will be created. - (self as u32).wrapping_sub('0' as u32) - } else { - match self { - '0'..='9' => self as u32 - '0' as u32, - 'a'..='z' => self as u32 - 'a' as u32 + 10, - 'A'..='Z' => self as u32 - 'A' as u32 + 10, - _ => return None, + // If not a digit, a number greater than radix will be created. + let mut digit = (self as u32).wrapping_sub('0' as u32); + if radix > 10 { + if digit < 10 { + return Some(digit); } - }; - - if val < radix { Some(val) } else { None } + // Force the 6th bit to be set to ensure ascii is lower case. + digit = (self as u32 | 0b10_0000).wrapping_sub('a' as u32).saturating_add(10); + } + (digit < radix).then_some(digit) } /// Returns an iterator that yields the hexadecimal Unicode escape of a diff --git a/library/core/src/lib.rs b/library/core/src/lib.rs index e10e1738de5..4353d2cda8a 100644 --- a/library/core/src/lib.rs +++ b/library/core/src/lib.rs @@ -66,6 +66,7 @@ #![feature(allow_internal_unstable)] #![feature(arbitrary_self_types)] #![feature(asm)] +#![feature(bool_to_option)] #![feature(cfg_target_has_atomic)] #![feature(const_heap)] #![feature(const_alloc_layout)] diff --git a/library/core/tests/char.rs b/library/core/tests/char.rs index c16f54081ce..51eca1e05d3 100644 --- a/library/core/tests/char.rs +++ b/library/core/tests/char.rs @@ -67,10 +67,20 @@ fn test_to_digit() { assert_eq!('A'.to_digit(16), Some(10)); assert_eq!('b'.to_digit(16), Some(11)); assert_eq!('B'.to_digit(16), Some(11)); + assert_eq!('A'.to_digit(36), Some(10)); assert_eq!('z'.to_digit(36), Some(35)); assert_eq!('Z'.to_digit(36), Some(35)); - assert_eq!(' '.to_digit(10), None); + assert_eq!('['.to_digit(36), None); + assert_eq!('`'.to_digit(36), None); + assert_eq!('{'.to_digit(36), None); assert_eq!('$'.to_digit(36), None); + assert_eq!('@'.to_digit(16), None); + assert_eq!('G'.to_digit(16), None); + assert_eq!('g'.to_digit(16), None); + assert_eq!(' '.to_digit(10), None); + assert_eq!('/'.to_digit(10), None); + assert_eq!(':'.to_digit(10), None); + assert_eq!(':'.to_digit(11), None); } #[test] |