// Copyright 2013-2014 The Rust Project Developers. See the COPYRIGHT // file at the top-level directory of this distribution and at // http://rust-lang.org/COPYRIGHT. // // Licensed under the Apache License, Version 2.0 or the MIT license // , at your // option. This file may not be copied, modified, or distributed // except according to those terms. //! Operations on ASCII strings and characters. //! //! Most string operations in Rust act on UTF-8 strings. However, at times it //! makes more sense to only consider the ASCII character set for a specific //! operation. //! //! The [`escape_default`] function provides an iterator over the bytes of an //! escaped version of the character given. //! //! [`escape_default`]: fn.escape_default.html #![stable(feature = "rust1", since = "1.0.0")] use fmt; use ops::Range; use iter::FusedIterator; /// An iterator over the escaped version of a byte. /// /// This `struct` is created by the [`escape_default`] function. See its /// documentation for more. /// /// [`escape_default`]: fn.escape_default.html #[unstable(feature = "core_ascii", issue = "46409")] pub struct EscapeDefault { range: Range, data: [u8; 4], } /// Returns an iterator that produces an escaped version of a `u8`. /// /// The default is chosen with a bias toward producing literals that are /// legal in a variety of languages, including C++11 and similar C-family /// languages. The exact rules are: /// /// * Tab is escaped as `\t`. /// * Carriage return is escaped as `\r`. /// * Line feed is escaped as `\n`. /// * Single quote is escaped as `\'`. /// * Double quote is escaped as `\"`. /// * Backslash is escaped as `\\`. /// * Any character in the 'printable ASCII' range `0x20` .. `0x7e` /// inclusive is not escaped. /// * Any other chars are given hex escapes of the form '\xNN'. /// * Unicode escapes are never generated by this function. /// /// # Examples /// /// ``` /// #![no_std] /// use core::ascii; /// /// let escaped = ascii::escape_default(b'0').next().unwrap(); /// assert_eq!(b'0', escaped); /// /// let mut escaped = ascii::escape_default(b'\t'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b't', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'\r'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'r', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'\n'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'n', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'\''); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'\'', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'"'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'"', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'\\'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'\\', escaped.next().unwrap()); /// /// let mut escaped = ascii::escape_default(b'\x9d'); /// /// assert_eq!(b'\\', escaped.next().unwrap()); /// assert_eq!(b'x', escaped.next().unwrap()); /// assert_eq!(b'9', escaped.next().unwrap()); /// assert_eq!(b'd', escaped.next().unwrap()); /// ``` #[unstable(feature = "core_ascii", issue = "46409")] pub fn escape_default(c: u8) -> EscapeDefault { let (data, len) = match c { b'\t' => ([b'\\', b't', 0, 0], 2), b'\r' => ([b'\\', b'r', 0, 0], 2), b'\n' => ([b'\\', b'n', 0, 0], 2), b'\\' => ([b'\\', b'\\', 0, 0], 2), b'\'' => ([b'\\', b'\'', 0, 0], 2), b'"' => ([b'\\', b'"', 0, 0], 2), b'\x20' ... b'\x7e' => ([c, 0, 0, 0], 1), _ => ([b'\\', b'x', hexify(c >> 4), hexify(c & 0xf)], 4), }; return EscapeDefault { range: 0..len, data }; fn hexify(b: u8) -> u8 { match b { 0 ... 9 => b'0' + b, _ => b'a' + b - 10, } } } #[stable(feature = "rust1", since = "1.0.0")] impl Iterator for EscapeDefault { type Item = u8; fn next(&mut self) -> Option { self.range.next().map(|i| self.data[i]) } fn size_hint(&self) -> (usize, Option) { self.range.size_hint() } } #[stable(feature = "rust1", since = "1.0.0")] impl DoubleEndedIterator for EscapeDefault { fn next_back(&mut self) -> Option { self.range.next_back().map(|i| self.data[i]) } } #[stable(feature = "rust1", since = "1.0.0")] impl ExactSizeIterator for EscapeDefault {} #[unstable(feature = "fused", issue = "35602")] impl FusedIterator for EscapeDefault {} #[stable(feature = "std_debug", since = "1.16.0")] impl fmt::Debug for EscapeDefault { fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result { f.pad("EscapeDefault { .. }") } } #[cfg(test)] mod tests { use char::from_u32; #[test] fn test_is_ascii() { assert!(b"".is_ascii()); assert!(b"banana\0\x7F".is_ascii()); assert!(b"banana\0\x7F".iter().all(|b| b.is_ascii())); assert!(!b"Vi\xe1\xbb\x87t Nam".is_ascii()); assert!(!b"Vi\xe1\xbb\x87t Nam".iter().all(|b| b.is_ascii())); assert!(!b"\xe1\xbb\x87".iter().any(|b| b.is_ascii())); assert!("".is_ascii()); assert!("banana\0\u{7F}".is_ascii()); assert!("banana\0\u{7F}".chars().all(|c| c.is_ascii())); assert!(!"ประเทศไทย中华Việt Nam".chars().all(|c| c.is_ascii())); assert!(!"ประเทศไทย中华ệ ".chars().any(|c| c.is_ascii())); } #[test] fn test_to_ascii_uppercase() { assert_eq!("url()URL()uRl()ürl".to_ascii_uppercase(), "URL()URL()URL()üRL"); assert_eq!("hıKß".to_ascii_uppercase(), "HıKß"); for i in 0..501 { let upper = if 'a' as u32 <= i && i <= 'z' as u32 { i + 'A' as u32 - 'a' as u32 } else { i }; assert_eq!((from_u32(i).unwrap()).to_string().to_ascii_uppercase(), (from_u32(upper).unwrap()).to_string()); } } #[test] fn test_to_ascii_lowercase() { assert_eq!("url()URL()uRl()Ürl".to_ascii_lowercase(), "url()url()url()Ürl"); // Dotted capital I, Kelvin sign, Sharp S. assert_eq!("HİKß".to_ascii_lowercase(), "hİKß"); for i in 0..501 { let lower = if 'A' as u32 <= i && i <= 'Z' as u32 { i + 'a' as u32 - 'A' as u32 } else { i }; assert_eq!((from_u32(i).unwrap()).to_string().to_ascii_lowercase(), (from_u32(lower).unwrap()).to_string()); } } #[test] fn test_make_ascii_lower_case() { macro_rules! test { ($from: expr, $to: expr) => { { let mut x = $from; x.make_ascii_lowercase(); assert_eq!(x, $to); } } } test!(b'A', b'a'); test!(b'a', b'a'); test!(b'!', b'!'); test!('A', 'a'); test!('À', 'À'); test!('a', 'a'); test!('!', '!'); test!(b"H\xc3\x89".to_vec(), b"h\xc3\x89"); test!("HİKß".to_string(), "hİKß"); } #[test] fn test_make_ascii_upper_case() { macro_rules! test { ($from: expr, $to: expr) => { { let mut x = $from; x.make_ascii_uppercase(); assert_eq!(x, $to); } } } test!(b'a', b'A'); test!(b'A', b'A'); test!(b'!', b'!'); test!('a', 'A'); test!('à', 'à'); test!('A', 'A'); test!('!', '!'); test!(b"h\xc3\xa9".to_vec(), b"H\xc3\xa9"); test!("hıKß".to_string(), "HıKß"); let mut x = "Hello".to_string(); x[..3].make_ascii_uppercase(); // Test IndexMut on String. assert_eq!(x, "HELlo") } #[test] fn test_eq_ignore_ascii_case() { assert!("url()URL()uRl()Ürl".eq_ignore_ascii_case("url()url()url()Ürl")); assert!(!"Ürl".eq_ignore_ascii_case("ürl")); // Dotted capital I, Kelvin sign, Sharp S. assert!("HİKß".eq_ignore_ascii_case("hİKß")); assert!(!"İ".eq_ignore_ascii_case("i")); assert!(!"K".eq_ignore_ascii_case("k")); assert!(!"ß".eq_ignore_ascii_case("s")); for i in 0..501 { let lower = if 'A' as u32 <= i && i <= 'Z' as u32 { i + 'a' as u32 - 'A' as u32 } else { i }; assert!((from_u32(i).unwrap()).to_string().eq_ignore_ascii_case( &from_u32(lower).unwrap().to_string())); } } #[test] fn inference_works() { let x = "a".to_string(); x.eq_ignore_ascii_case("A"); } // Shorthands used by the is_ascii_* tests. macro_rules! assert_all { ($what:ident, $($str:tt),+) => {{ $( for b in $str.chars() { if !b.$what() { panic!("expected {}({}) but it isn't", stringify!($what), b); } } for b in $str.as_bytes().iter() { if !b.$what() { panic!("expected {}(0x{:02x})) but it isn't", stringify!($what), b); } } assert!($str.$what()); assert!($str.as_bytes().$what()); )+ }}; ($what:ident, $($str:tt),+,) => (assert_all!($what,$($str),+)) } macro_rules! assert_none { ($what:ident, $($str:tt),+) => {{ $( for b in $str.chars() { if b.$what() { panic!("expected not-{}({}) but it is", stringify!($what), b); } } for b in $str.as_bytes().iter() { if b.$what() { panic!("expected not-{}(0x{:02x})) but it is", stringify!($what), b); } } )* }}; ($what:ident, $($str:tt),+,) => (assert_none!($what,$($str),+)) } #[test] fn test_is_ascii_alphabetic() { assert_all!(is_ascii_alphabetic, "", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", ); assert_none!(is_ascii_alphabetic, "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_uppercase() { assert_all!(is_ascii_uppercase, "", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", ); assert_none!(is_ascii_uppercase, "abcdefghijklmnopqrstuvwxyz", "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_lowercase() { assert_all!(is_ascii_lowercase, "abcdefghijklmnopqrstuvwxyz", ); assert_none!(is_ascii_lowercase, "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_alphanumeric() { assert_all!(is_ascii_alphanumeric, "", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", ); assert_none!(is_ascii_alphanumeric, "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_digit() { assert_all!(is_ascii_digit, "", "0123456789", ); assert_none!(is_ascii_digit, "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_hexdigit() { assert_all!(is_ascii_hexdigit, "", "0123456789", "abcdefABCDEF", ); assert_none!(is_ascii_hexdigit, "ghijklmnopqrstuvwxyz", "GHIJKLMNOQPRSTUVWXYZ", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_punctuation() { assert_all!(is_ascii_punctuation, "", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", ); assert_none!(is_ascii_punctuation, "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_graphic() { assert_all!(is_ascii_graphic, "", "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", ); assert_none!(is_ascii_graphic, " \t\n\x0c\r", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_whitespace() { assert_all!(is_ascii_whitespace, "", " \t\n\x0c\r", ); assert_none!(is_ascii_whitespace, "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x0b\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); } #[test] fn test_is_ascii_control() { assert_all!(is_ascii_control, "", "\x00\x01\x02\x03\x04\x05\x06\x07", "\x08\x09\x0a\x0b\x0c\x0d\x0e\x0f", "\x10\x11\x12\x13\x14\x15\x16\x17", "\x18\x19\x1a\x1b\x1c\x1d\x1e\x1f", "\x7f", ); assert_none!(is_ascii_control, "abcdefghijklmnopqrstuvwxyz", "ABCDEFGHIJKLMNOQPRSTUVWXYZ", "0123456789", "!\"#$%&'()*+,-./:;<=>?@[\\]^_`{|}~", " ", ); } }