vendor/percent-encoding-1.0.1/lib.rs - toolchain/rustc - Git at Google

 // Copyright 2013-2016 The rust-url developers.
 //
 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
 // option. This file may not be copied, modified, or distributed
 // except according to those terms.

 //! URLs use special chacters to indicate the parts of the request.  For example, a forward slash
 //! indicates a path.  In order for that charcter to exist outside of a path separator, that
 //! charcter would need to be encoded.
 //!
 //! Percent encoding replaces reserved charcters with the `%` escape charcter followed by hexidecimal
 //! ASCII representaton.  For non-ASCII charcters that are percent encoded, a UTF-8 byte sequence
 //! becomes percent encoded.  A simple example can be seen when the space literal is replaced with
 //! `%20`.
 //!
 //! Percent encoding is further complicated by the fact that different parts of an URL have
 //! different encoding requirements.  In order to support the variety of encoding requirements,
 //! `url::percent_encoding` includes different *encode sets*.
 //! See [URL Standard](https://url.spec.whatwg.org/#percent-encoded-bytes) for details.
 //!
 //! This module provides some `*_ENCODE_SET` constants.
 //! If a different set is required, it can be created with
 //! the [`define_encode_set!`](../macro.define_encode_set!.html) macro.
 //!
 //! # Examples
 //!
 //! ```
 //! use url::percent_encoding::{utf8_percent_encode, DEFAULT_ENCODE_SET};
 //!
 //! assert_eq!(utf8_percent_encode("foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
 //! ```

 use std::ascii::AsciiExt;
 use std::borrow::Cow;
 use std::fmt;
 use std::slice;
 use std::str;

 /// Represents a set of characters / bytes that should be percent-encoded.
 ///
 /// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set).
 ///
 /// Different characters need to be encoded in different parts of an URL.
 /// For example, a literal `?` question mark in an URL’s path would indicate
 /// the start of the query string.
 /// A question mark meant to be part of the path therefore needs to be percent-encoded.
 /// In the query string however, a question mark does not have any special meaning
 /// and does not need to be percent-encoded.
 ///
 /// A few sets are defined in this module.
 /// Use the [`define_encode_set!`](../macro.define_encode_set!.html) macro to define different ones.
 pub trait EncodeSet: Clone {
     /// Called with UTF-8 bytes rather than code points.
     /// Should return true for all non-ASCII bytes.
     fn contains(&self, byte: u8) -> bool;
 }

 /// Define a new struct
 /// that implements the [`EncodeSet`](percent_encoding/trait.EncodeSet.html) trait,
 /// for use in [`percent_decode()`](percent_encoding/fn.percent_encode.html)
 /// and related functions.
 ///
 /// Parameters are characters to include in the set in addition to those of the base set.
 /// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set).
 ///
 /// Example
 /// =======
 ///
 /// ```rust
 /// #[macro_use] extern crate percent_encoding;
 /// use percent_encoding::{utf8_percent_encode, SIMPLE_ENCODE_SET};
 /// define_encode_set! {
 ///     /// This encode set is used in the URL parser for query strings.
 ///     pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] | {' ', '"', '#', '<', '>'}
 /// }
 /// # fn main() {
 /// assert_eq!(utf8_percent_encode("foo bar", QUERY_ENCODE_SET).collect::<String>(), "foo%20bar");
 /// # }
 /// ```
 #[macro_export]
 macro_rules! define_encode_set {
     ($(#[$attr: meta])* pub $name: ident = [$base_set: expr] | {$($ch: pat),*}) => {
         $(#[$attr])*
         #[derive(Copy, Clone, Debug)]
         #[allow(non_camel_case_types)]
         pub struct $name;

         impl $crate::EncodeSet for $name {
             #[inline]
             fn contains(&self, byte: u8) -> bool {
                 match byte as char {
                     $(
                         $ch => true,
                     )*
                     _ => $base_set.contains(byte)
                 }
             }
         }
     }
 }

 /// This encode set is used for the path of cannot-be-a-base URLs.
 ///
 /// All ASCII charcters less than hexidecimal 20 and greater than 7E are encoded.  This includes
 /// special charcters such as line feed, carriage return, NULL, etc.
 #[derive(Copy, Clone, Debug)]
 #[allow(non_camel_case_types)]
 pub struct SIMPLE_ENCODE_SET;

 impl EncodeSet for SIMPLE_ENCODE_SET {
     #[inline]
     fn contains(&self, byte: u8) -> bool {
         byte < 0x20 || byte > 0x7E
     }
 }

 define_encode_set! {
     /// This encode set is used in the URL parser for query strings.
     ///
     /// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
     /// space, double quote ("), hash (#), and inequality qualifiers (<), (>) are encoded.
     pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] | {' ', '"', '#', '<', '>'}
 }

 define_encode_set! {
     /// This encode set is used for path components.
     ///
     /// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
     /// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
     /// question mark (?), and curly brackets ({), (}) are encoded.
     pub DEFAULT_ENCODE_SET = [QUERY_ENCODE_SET] | {'`', '?', '{', '}'}
 }

 define_encode_set! {
     /// This encode set is used for on '/'-separated path segment
     ///
     /// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
     /// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
     /// question mark (?), and curly brackets ({), (}), percent sign (%), forward slash (/) are
     /// encoded.
     pub PATH_SEGMENT_ENCODE_SET = [DEFAULT_ENCODE_SET] | {'%', '/'}
 }

 define_encode_set! {
     /// This encode set is used for username and password.
     ///
     /// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
     /// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
     /// question mark (?), and curly brackets ({), (}), forward slash (/), colon (:), semi-colon (;),
     /// equality (=), at (@), backslash (\\), square brackets ([), (]), caret (\^), and pipe (|) are
     /// encoded.
     pub USERINFO_ENCODE_SET = [DEFAULT_ENCODE_SET] | {
         '/', ':', ';', '=', '@', '[', '\\', ']', '^', '|'
     }
 }

 /// Return the percent-encoding of the given bytes.
 ///
 /// This is unconditional, unlike `percent_encode()` which uses an encode set.
 ///
 /// # Examples
 ///
 /// ```
 /// use url::percent_encoding::percent_encode_byte;
 ///
 /// assert_eq!("foo bar".bytes().map(percent_encode_byte).collect::<String>(),
 ///            "%66%6F%6F%20%62%61%72");
 /// ```
 pub fn percent_encode_byte(byte: u8) -> &'static str {
     let index = usize::from(byte) * 3;
     &"\
         %00%01%02%03%04%05%06%07%08%09%0A%0B%0C%0D%0E%0F\
         %10%11%12%13%14%15%16%17%18%19%1A%1B%1C%1D%1E%1F\
         %20%21%22%23%24%25%26%27%28%29%2A%2B%2C%2D%2E%2F\
         %30%31%32%33%34%35%36%37%38%39%3A%3B%3C%3D%3E%3F\
         %40%41%42%43%44%45%46%47%48%49%4A%4B%4C%4D%4E%4F\
         %50%51%52%53%54%55%56%57%58%59%5A%5B%5C%5D%5E%5F\
         %60%61%62%63%64%65%66%67%68%69%6A%6B%6C%6D%6E%6F\
         %70%71%72%73%74%75%76%77%78%79%7A%7B%7C%7D%7E%7F\
         %80%81%82%83%84%85%86%87%88%89%8A%8B%8C%8D%8E%8F\
         %90%91%92%93%94%95%96%97%98%99%9A%9B%9C%9D%9E%9F\
         %A0%A1%A2%A3%A4%A5%A6%A7%A8%A9%AA%AB%AC%AD%AE%AF\
         %B0%B1%B2%B3%B4%B5%B6%B7%B8%B9%BA%BB%BC%BD%BE%BF\
         %C0%C1%C2%C3%C4%C5%C6%C7%C8%C9%CA%CB%CC%CD%CE%CF\
         %D0%D1%D2%D3%D4%D5%D6%D7%D8%D9%DA%DB%DC%DD%DE%DF\
         %E0%E1%E2%E3%E4%E5%E6%E7%E8%E9%EA%EB%EC%ED%EE%EF\
         %F0%F1%F2%F3%F4%F5%F6%F7%F8%F9%FA%FB%FC%FD%FE%FF\
     "[index..index + 3]
 }

 /// Percent-encode the given bytes with the given encode set.
 ///
 /// The encode set define which bytes (in addition to non-ASCII and controls)
 /// need to be percent-encoded.
 /// The choice of this set depends on context.
 /// For example, `?` needs to be encoded in an URL path but not in a query string.
 ///
 /// The return value is an iterator of `&str` slices (so it has a `.collect::<String>()` method)
 /// that also implements `Display` and `Into<Cow<str>>`.
 /// The latter returns `Cow::Borrowed` when none of the bytes in `input`
 /// are in the given encode set.
 ///
 /// # Examples
 ///
 /// ```
 /// use url::percent_encoding::{percent_encode, DEFAULT_ENCODE_SET};
 ///
 /// assert_eq!(percent_encode(b"foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
 /// ```
 #[inline]
 pub fn percent_encode<E: EncodeSet>(input: &[u8], encode_set: E) -> PercentEncode<E> {
     PercentEncode {
         bytes: input,
         encode_set: encode_set,
     }
 }

 /// Percent-encode the UTF-8 encoding of the given string.
 ///
 /// See `percent_encode()` for how to use the return value.
 ///
 /// # Examples
 ///
 /// ```
 /// use url::percent_encoding::{utf8_percent_encode, DEFAULT_ENCODE_SET};
 ///
 /// assert_eq!(utf8_percent_encode("foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
 /// ```
 #[inline]
 pub fn utf8_percent_encode<E: EncodeSet>(input: &str, encode_set: E) -> PercentEncode<E> {
     percent_encode(input.as_bytes(), encode_set)
 }

 /// The return type of `percent_encode()` and `utf8_percent_encode()`.
 #[derive(Clone, Debug)]
 pub struct PercentEncode<'a, E: EncodeSet> {
     bytes: &'a [u8],
     encode_set: E,
 }

 impl<'a, E: EncodeSet> Iterator for PercentEncode<'a, E> {
     type Item = &'a str;

     fn next(&mut self) -> Option<&'a str> {
         if let Some((&first_byte, remaining)) = self.bytes.split_first() {
             if self.encode_set.contains(first_byte) {
                 self.bytes = remaining;
                 Some(percent_encode_byte(first_byte))
             } else {
                 assert!(first_byte.is_ascii());
                 for (i, &byte) in remaining.iter().enumerate() {
                     if self.encode_set.contains(byte) {
                         // 1 for first_byte + i for previous iterations of this loop
                         let (unchanged_slice, remaining) = self.bytes.split_at(1 + i);
                         self.bytes = remaining;
                         return Some(unsafe { str::from_utf8_unchecked(unchanged_slice) })
                     } else {
                         assert!(byte.is_ascii());
                     }
                 }
                 let unchanged_slice = self.bytes;
                 self.bytes = &[][..];
                 Some(unsafe { str::from_utf8_unchecked(unchanged_slice) })
             }
         } else {
             None
         }
     }

     fn size_hint(&self) -> (usize, Option<usize>) {
         if self.bytes.is_empty() {
             (0, Some(0))
         } else {
             (1, Some(self.bytes.len()))
         }
     }
 }

 impl<'a, E: EncodeSet> fmt::Display for PercentEncode<'a, E> {
     fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
         for c in (*self).clone() {
             formatter.write_str(c)?
         }
         Ok(())
     }
 }

 impl<'a, E: EncodeSet> From<PercentEncode<'a, E>> for Cow<'a, str> {
     fn from(mut iter: PercentEncode<'a, E>) -> Self {
         match iter.next() {
             None => "".into(),
             Some(first) => {
                 match iter.next() {
                     None => first.into(),
                     Some(second) => {
                         let mut string = first.to_owned();
                         string.push_str(second);
                         string.extend(iter);
                         string.into()
                     }
                 }
             }
         }
     }
 }

 /// Percent-decode the given bytes.
 ///
 /// The return value is an iterator of decoded `u8` bytes
 /// that also implements `Into<Cow<u8>>`
 /// (which returns `Cow::Borrowed` when `input` contains no percent-encoded sequence)
 /// and has `decode_utf8()` and `decode_utf8_lossy()` methods.
 ///
 /// # Examples
 ///
 /// ```
 /// use url::percent_encoding::percent_decode;
 ///
 /// assert_eq!(percent_decode(b"foo%20bar%3F").decode_utf8().unwrap(), "foo bar?");
 /// ```
 #[inline]
 pub fn percent_decode(input: &[u8]) -> PercentDecode {
     PercentDecode {
         bytes: input.iter()
     }
 }

 /// The return type of `percent_decode()`.
 #[derive(Clone, Debug)]
 pub struct PercentDecode<'a> {
     bytes: slice::Iter<'a, u8>,
 }

 fn after_percent_sign(iter: &mut slice::Iter<u8>) -> Option<u8> {
     let initial_iter = iter.clone();
     let h = iter.next().and_then(|&b| (b as char).to_digit(16));
     let l = iter.next().and_then(|&b| (b as char).to_digit(16));
     if let (Some(h), Some(l)) = (h, l) {
         Some(h as u8 * 0x10 + l as u8)
     } else {
         *iter = initial_iter;
         None
     }
 }

 impl<'a> Iterator for PercentDecode<'a> {
     type Item = u8;

     fn next(&mut self) -> Option<u8> {
         self.bytes.next().map(|&byte| {
             if byte == b'%' {
                 after_percent_sign(&mut self.bytes).unwrap_or(byte)
             } else {
                 byte
             }
         })
     }

     fn size_hint(&self) -> (usize, Option<usize>) {
         let bytes = self.bytes.len();
         (bytes / 3, Some(bytes))
     }
 }

 impl<'a> From<PercentDecode<'a>> for Cow<'a, [u8]> {
     fn from(iter: PercentDecode<'a>) -> Self {
         match iter.if_any() {
             Some(vec) => Cow::Owned(vec),
             None => Cow::Borrowed(iter.bytes.as_slice()),
         }
     }
 }

 impl<'a> PercentDecode<'a> {
     /// If the percent-decoding is different from the input, return it as a new bytes vector.
     pub fn if_any(&self) -> Option<Vec<u8>> {
         let mut bytes_iter = self.bytes.clone();
         while bytes_iter.any(|&b| b == b'%') {
             if let Some(decoded_byte) = after_percent_sign(&mut bytes_iter) {
                 let initial_bytes = self.bytes.as_slice();
                 let unchanged_bytes_len = initial_bytes.len() - bytes_iter.len() - 3;
                 let mut decoded = initial_bytes[..unchanged_bytes_len].to_owned();
                 decoded.push(decoded_byte);
                 decoded.extend(PercentDecode {
                     bytes: bytes_iter
                 });
                 return Some(decoded)
             }
         }
         // Nothing to decode
         None
     }

     /// Decode the result of percent-decoding as UTF-8.
     ///
     /// This is return `Err` when the percent-decoded bytes are not well-formed in UTF-8.
     pub fn decode_utf8(self) -> Result<Cow<'a, str>, str::Utf8Error> {
         match self.clone().into() {
             Cow::Borrowed(bytes) => {
                 match str::from_utf8(bytes) {
                     Ok(s) => Ok(s.into()),
                     Err(e) => Err(e),
                 }
             }
             Cow::Owned(bytes) => {
                 match String::from_utf8(bytes) {
                     Ok(s) => Ok(s.into()),
                     Err(e) => Err(e.utf8_error()),
                 }
             }
         }
     }

     /// Decode the result of percent-decoding as UTF-8, lossily.
     ///
     /// Invalid UTF-8 percent-encoded byte sequences will be replaced � U+FFFD,
     /// the replacement character.
     pub fn decode_utf8_lossy(self) -> Cow<'a, str> {
         decode_utf8_lossy(self.clone().into())
     }
 }

 fn decode_utf8_lossy(input: Cow<[u8]>) -> Cow<str> {
     match input {
         Cow::Borrowed(bytes) => String::from_utf8_lossy(bytes),
         Cow::Owned(bytes) => {
             let raw_utf8: *const [u8];
             match String::from_utf8_lossy(&bytes) {
                 Cow::Borrowed(utf8) => raw_utf8 = utf8.as_bytes(),
                 Cow::Owned(s) => return s.into(),
             }
             // from_utf8_lossy returned a borrow of `bytes` unchanged.
             debug_assert!(raw_utf8 == &*bytes as *const [u8]);
             // Reuse the existing `Vec` allocation.
             unsafe { String::from_utf8_unchecked(bytes) }.into()
         }
     }
 }
	// Copyright 2013-2016 The rust-url developers.
	//
	// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
	// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
	// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
	// option. This file may not be copied, modified, or distributed
	// except according to those terms.

	//! URLs use special chacters to indicate the parts of the request. For example, a forward slash
	//! indicates a path. In order for that charcter to exist outside of a path separator, that
	//! charcter would need to be encoded.
	//!
	//! Percent encoding replaces reserved charcters with the `%` escape charcter followed by hexidecimal
	//! ASCII representaton. For non-ASCII charcters that are percent encoded, a UTF-8 byte sequence
	//! becomes percent encoded. A simple example can be seen when the space literal is replaced with
	//! `%20`.
	//!
	//! Percent encoding is further complicated by the fact that different parts of an URL have
	//! different encoding requirements. In order to support the variety of encoding requirements,
	//! `url::percent_encoding` includes different encode sets.
	//! See [URL Standard](https://url.spec.whatwg.org/#percent-encoded-bytes) for details.
	//!
	//! This module provides some `*_ENCODE_SET` constants.
	//! If a different set is required, it can be created with
	//! the [`define_encode_set!`](../macro.define_encode_set!.html) macro.
	//!
	//! # Examples
	//!
	//! ```
	//! use url::percent_encoding::{utf8_percent_encode, DEFAULT_ENCODE_SET};
	//!
	//! assert_eq!(utf8_percent_encode("foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
	//! ```

	use std::ascii::AsciiExt;
	use std::borrow::Cow;
	use std::fmt;
	use std::slice;
	use std::str;

	/// Represents a set of characters / bytes that should be percent-encoded.
	///
	/// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set).
	///
	/// Different characters need to be encoded in different parts of an URL.
	/// For example, a literal `?` question mark in an URL’s path would indicate
	/// the start of the query string.
	/// A question mark meant to be part of the path therefore needs to be percent-encoded.
	/// In the query string however, a question mark does not have any special meaning
	/// and does not need to be percent-encoded.
	///
	/// A few sets are defined in this module.
	/// Use the [`define_encode_set!`](../macro.define_encode_set!.html) macro to define different ones.
	pub trait EncodeSet: Clone {
	/// Called with UTF-8 bytes rather than code points.
	/// Should return true for all non-ASCII bytes.
	fn contains(&self, byte: u8) -> bool;
	}

	/// Define a new struct
	/// that implements the [`EncodeSet`](percent_encoding/trait.EncodeSet.html) trait,
	/// for use in [`percent_decode()`](percent_encoding/fn.percent_encode.html)
	/// and related functions.
	///
	/// Parameters are characters to include in the set in addition to those of the base set.
	/// See [encode sets specification](http://url.spec.whatwg.org/#simple-encode-set).
	///
	/// Example
	/// =======
	///
	/// ```rust
	/// #[macro_use] extern crate percent_encoding;
	/// use percent_encoding::{utf8_percent_encode, SIMPLE_ENCODE_SET};
	/// define_encode_set! {
	/// /// This encode set is used in the URL parser for query strings.
	/// pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] \| {' ', '"', '#', '<', '>'}
	/// }
	/// # fn main() {
	/// assert_eq!(utf8_percent_encode("foo bar", QUERY_ENCODE_SET).collect::<String>(), "foo%20bar");
	/// # }
	/// ```
	#[macro_export]
	macro_rules! define_encode_set {
	($(#[$attr: meta])* pub $name: ident = [$base_set: expr] \| {$($ch: pat),*}) => {
	$(#[$attr])*
	#[derive(Copy, Clone, Debug)]
	#[allow(non_camel_case_types)]
	pub struct $name;

	impl $crate::EncodeSet for $name {
	#[inline]
	fn contains(&self, byte: u8) -> bool {
	match byte as char {
	$(
	$ch => true,
	)*
	_ => $base_set.contains(byte)
	}
	}
	}
	}
	}

	/// This encode set is used for the path of cannot-be-a-base URLs.
	///
	/// All ASCII charcters less than hexidecimal 20 and greater than 7E are encoded. This includes
	/// special charcters such as line feed, carriage return, NULL, etc.
	#[derive(Copy, Clone, Debug)]
	#[allow(non_camel_case_types)]
	pub struct SIMPLE_ENCODE_SET;

	impl EncodeSet for SIMPLE_ENCODE_SET {
	#[inline]
	fn contains(&self, byte: u8) -> bool {
	byte < 0x20 \|\| byte > 0x7E
	}
	}

	define_encode_set! {
	/// This encode set is used in the URL parser for query strings.
	///
	/// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
	/// space, double quote ("), hash (#), and inequality qualifiers (<), (>) are encoded.
	pub QUERY_ENCODE_SET = [SIMPLE_ENCODE_SET] \| {' ', '"', '#', '<', '>'}
	}

	define_encode_set! {
	/// This encode set is used for path components.
	///
	/// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
	/// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
	/// question mark (?), and curly brackets ({), (}) are encoded.
	pub DEFAULT_ENCODE_SET = [QUERY_ENCODE_SET] \| {'`', '?', '{', '}'}
	}

	define_encode_set! {
	/// This encode set is used for on '/'-separated path segment
	///
	/// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
	/// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
	/// question mark (?), and curly brackets ({), (}), percent sign (%), forward slash (/) are
	/// encoded.
	pub PATH_SEGMENT_ENCODE_SET = [DEFAULT_ENCODE_SET] \| {'%', '/'}
	}

	define_encode_set! {
	/// This encode set is used for username and password.
	///
	/// Aside from special chacters defined in the [`SIMPLE_ENCODE_SET`](struct.SIMPLE_ENCODE_SET.html),
	/// space, double quote ("), hash (#), inequality qualifiers (<), (>), backtick (`),
	/// question mark (?), and curly brackets ({), (}), forward slash (/), colon (:), semi-colon (;),
	/// equality (=), at (@), backslash (\\), square brackets ([), (]), caret (\^), and pipe (\|) are
	/// encoded.
	pub USERINFO_ENCODE_SET = [DEFAULT_ENCODE_SET] \| {
	'/', ':', ';', '=', '@', '[', '\\', ']', '^', '\|'
	}
	}

	/// Return the percent-encoding of the given bytes.
	///
	/// This is unconditional, unlike `percent_encode()` which uses an encode set.
	///
	/// # Examples
	///
	/// ```
	/// use url::percent_encoding::percent_encode_byte;
	///
	/// assert_eq!("foo bar".bytes().map(percent_encode_byte).collect::<String>(),
	/// "%66%6F%6F%20%62%61%72");
	/// ```
	pub fn percent_encode_byte(byte: u8) -> &'static str {
	let index = usize::from(byte) * 3;
	&"\
	%00%01%02%03%04%05%06%07%08%09%0A%0B%0C%0D%0E%0F\
	%10%11%12%13%14%15%16%17%18%19%1A%1B%1C%1D%1E%1F\
	%20%21%22%23%24%25%26%27%28%29%2A%2B%2C%2D%2E%2F\
	%30%31%32%33%34%35%36%37%38%39%3A%3B%3C%3D%3E%3F\
	%40%41%42%43%44%45%46%47%48%49%4A%4B%4C%4D%4E%4F\
	%50%51%52%53%54%55%56%57%58%59%5A%5B%5C%5D%5E%5F\
	%60%61%62%63%64%65%66%67%68%69%6A%6B%6C%6D%6E%6F\
	%70%71%72%73%74%75%76%77%78%79%7A%7B%7C%7D%7E%7F\
	%80%81%82%83%84%85%86%87%88%89%8A%8B%8C%8D%8E%8F\
	%90%91%92%93%94%95%96%97%98%99%9A%9B%9C%9D%9E%9F\
	%A0%A1%A2%A3%A4%A5%A6%A7%A8%A9%AA%AB%AC%AD%AE%AF\
	%B0%B1%B2%B3%B4%B5%B6%B7%B8%B9%BA%BB%BC%BD%BE%BF\
	%C0%C1%C2%C3%C4%C5%C6%C7%C8%C9%CA%CB%CC%CD%CE%CF\
	%D0%D1%D2%D3%D4%D5%D6%D7%D8%D9%DA%DB%DC%DD%DE%DF\
	%E0%E1%E2%E3%E4%E5%E6%E7%E8%E9%EA%EB%EC%ED%EE%EF\
	%F0%F1%F2%F3%F4%F5%F6%F7%F8%F9%FA%FB%FC%FD%FE%FF\
	"[index..index + 3]
	}

	/// Percent-encode the given bytes with the given encode set.
	///
	/// The encode set define which bytes (in addition to non-ASCII and controls)
	/// need to be percent-encoded.
	/// The choice of this set depends on context.
	/// For example, `?` needs to be encoded in an URL path but not in a query string.
	///
	/// The return value is an iterator of `&str` slices (so it has a `.collect::<String>()` method)
	/// that also implements `Display` and `Into<Cow<str>>`.
	/// The latter returns `Cow::Borrowed` when none of the bytes in `input`
	/// are in the given encode set.
	///
	/// # Examples
	///
	/// ```
	/// use url::percent_encoding::{percent_encode, DEFAULT_ENCODE_SET};
	///
	/// assert_eq!(percent_encode(b"foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
	/// ```
	#[inline]
	pub fn percent_encode<E: EncodeSet>(input: &[u8], encode_set: E) -> PercentEncode<E> {
	PercentEncode {
	bytes: input,
	encode_set: encode_set,
	}
	}

	/// Percent-encode the UTF-8 encoding of the given string.
	///
	/// See `percent_encode()` for how to use the return value.
	///
	/// # Examples
	///
	/// ```
	/// use url::percent_encoding::{utf8_percent_encode, DEFAULT_ENCODE_SET};
	///
	/// assert_eq!(utf8_percent_encode("foo bar?", DEFAULT_ENCODE_SET).to_string(), "foo%20bar%3F");
	/// ```
	#[inline]
	pub fn utf8_percent_encode<E: EncodeSet>(input: &str, encode_set: E) -> PercentEncode<E> {
	percent_encode(input.as_bytes(), encode_set)
	}

	/// The return type of `percent_encode()` and `utf8_percent_encode()`.
	#[derive(Clone, Debug)]
	pub struct PercentEncode<'a, E: EncodeSet> {
	bytes: &'a [u8],
	encode_set: E,
	}

	impl<'a, E: EncodeSet> Iterator for PercentEncode<'a, E> {
	type Item = &'a str;

	fn next(&mut self) -> Option<&'a str> {
	if let Some((&first_byte, remaining)) = self.bytes.split_first() {
	if self.encode_set.contains(first_byte) {
	self.bytes = remaining;
	Some(percent_encode_byte(first_byte))
	} else {
	assert!(first_byte.is_ascii());
	for (i, &byte) in remaining.iter().enumerate() {
	if self.encode_set.contains(byte) {
	// 1 for first_byte + i for previous iterations of this loop
	let (unchanged_slice, remaining) = self.bytes.split_at(1 + i);
	self.bytes = remaining;
	return Some(unsafe { str::from_utf8_unchecked(unchanged_slice) })
	} else {
	assert!(byte.is_ascii());
	}
	}
	let unchanged_slice = self.bytes;
	self.bytes = &[][..];
	Some(unsafe { str::from_utf8_unchecked(unchanged_slice) })
	}
	} else {
	None
	}
	}

	fn size_hint(&self) -> (usize, Option<usize>) {
	if self.bytes.is_empty() {
	(0, Some(0))
	} else {
	(1, Some(self.bytes.len()))
	}
	}
	}

	impl<'a, E: EncodeSet> fmt::Display for PercentEncode<'a, E> {
	fn fmt(&self, formatter: &mut fmt::Formatter) -> fmt::Result {
	for c in (*self).clone() {
	formatter.write_str(c)?
	}
	Ok(())
	}
	}

	impl<'a, E: EncodeSet> From<PercentEncode<'a, E>> for Cow<'a, str> {
	fn from(mut iter: PercentEncode<'a, E>) -> Self {
	match iter.next() {
	None => "".into(),
	Some(first) => {
	match iter.next() {
	None => first.into(),
	Some(second) => {
	let mut string = first.to_owned();
	string.push_str(second);
	string.extend(iter);
	string.into()
	}
	}
	}
	}
	}
	}

	/// Percent-decode the given bytes.
	///
	/// The return value is an iterator of decoded `u8` bytes
	/// that also implements `Into<Cow<u8>>`
	/// (which returns `Cow::Borrowed` when `input` contains no percent-encoded sequence)
	/// and has `decode_utf8()` and `decode_utf8_lossy()` methods.
	///
	/// # Examples
	///
	/// ```
	/// use url::percent_encoding::percent_decode;
	///
	/// assert_eq!(percent_decode(b"foo%20bar%3F").decode_utf8().unwrap(), "foo bar?");
	/// ```
	#[inline]
	pub fn percent_decode(input: &[u8]) -> PercentDecode {
	PercentDecode {
	bytes: input.iter()
	}
	}

	/// The return type of `percent_decode()`.
	#[derive(Clone, Debug)]
	pub struct PercentDecode<'a> {
	bytes: slice::Iter<'a, u8>,
	}

	fn after_percent_sign(iter: &mut slice::Iter<u8>) -> Option<u8> {
	let initial_iter = iter.clone();
	let h = iter.next().and_then(\|&b\| (b as char).to_digit(16));
	let l = iter.next().and_then(\|&b\| (b as char).to_digit(16));
	if let (Some(h), Some(l)) = (h, l) {
	Some(h as u8 * 0x10 + l as u8)
	} else {
	*iter = initial_iter;
	None
	}
	}

	impl<'a> Iterator for PercentDecode<'a> {
	type Item = u8;

	fn next(&mut self) -> Option<u8> {
	self.bytes.next().map(\|&byte\| {
	if byte == b'%' {
	after_percent_sign(&mut self.bytes).unwrap_or(byte)
	} else {
	byte
	}
	})
	}

	fn size_hint(&self) -> (usize, Option<usize>) {
	let bytes = self.bytes.len();
	(bytes / 3, Some(bytes))
	}
	}

	impl<'a> From<PercentDecode<'a>> for Cow<'a, [u8]> {
	fn from(iter: PercentDecode<'a>) -> Self {
	match iter.if_any() {
	Some(vec) => Cow::Owned(vec),
	None => Cow::Borrowed(iter.bytes.as_slice()),
	}
	}
	}

	impl<'a> PercentDecode<'a> {
	/// If the percent-decoding is different from the input, return it as a new bytes vector.
	pub fn if_any(&self) -> Option<Vec<u8>> {
	let mut bytes_iter = self.bytes.clone();
	while bytes_iter.any(\|&b\| b == b'%') {
	if let Some(decoded_byte) = after_percent_sign(&mut bytes_iter) {
	let initial_bytes = self.bytes.as_slice();
	let unchanged_bytes_len = initial_bytes.len() - bytes_iter.len() - 3;
	let mut decoded = initial_bytes[..unchanged_bytes_len].to_owned();
	decoded.push(decoded_byte);
	decoded.extend(PercentDecode {
	bytes: bytes_iter
	});
	return Some(decoded)
	}
	}
	// Nothing to decode
	None
	}

	/// Decode the result of percent-decoding as UTF-8.
	///
	/// This is return `Err` when the percent-decoded bytes are not well-formed in UTF-8.
	pub fn decode_utf8(self) -> Result<Cow<'a, str>, str::Utf8Error> {
	match self.clone().into() {
	Cow::Borrowed(bytes) => {
	match str::from_utf8(bytes) {
	Ok(s) => Ok(s.into()),
	Err(e) => Err(e),
	}
	}
	Cow::Owned(bytes) => {
	match String::from_utf8(bytes) {
	Ok(s) => Ok(s.into()),
	Err(e) => Err(e.utf8_error()),
	}
	}
	}
	}

	/// Decode the result of percent-decoding as UTF-8, lossily.
	///
	/// Invalid UTF-8 percent-encoded byte sequences will be replaced � U+FFFD,
	/// the replacement character.
	pub fn decode_utf8_lossy(self) -> Cow<'a, str> {
	decode_utf8_lossy(self.clone().into())
	}
	}

	fn decode_utf8_lossy(input: Cow<[u8]>) -> Cow<str> {
	match input {
	Cow::Borrowed(bytes) => String::from_utf8_lossy(bytes),
	Cow::Owned(bytes) => {
	let raw_utf8: *const [u8];
	match String::from_utf8_lossy(&bytes) {
	Cow::Borrowed(utf8) => raw_utf8 = utf8.as_bytes(),
	Cow::Owned(s) => return s.into(),
	}
	// from_utf8_lossy returned a borrow of `bytes` unchanged.
	debug_assert!(raw_utf8 == &bytes as const [u8]);
	// Reuse the existing `Vec` allocation.
	unsafe { String::from_utf8_unchecked(bytes) }.into()
	}
	}
	}