1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362
// This file is part of ICU4X. For terms of use, please see the file
// called LICENSE at the top level of the ICU4X source tree
// (online at: https://github.com/unicode-org/icu4x/blob/main/LICENSE ).
//! Unicode Extensions provide a mechanism to extend the [`LanguageIdentifier`] with
//! additional bits of information - a combination of a [`LanguageIdentifier`] and [`Extensions`]
//! is called [`Locale`].
//!
//! There are four types of extensions:
//!
//! * [`Unicode Extensions`] - marked as `u`.
//! * [`Transform Extensions`] - marked as `t`.
//! * [`Private Use Extensions`] - marked as `x`.
//! * [`Other Extensions`] - marked as any `a-z` except of `u`, `t` and `x`.
//!
//! One can think of extensions as a bag of extra information on top of basic 4 [`subtags`].
//!
//! Notice: `Other` extension type is currently not supported.
//!
//! # Examples
//!
//! ```
//! use icu::locid::extensions::unicode::{Key, Value};
//! use icu::locid::Locale;
//!
//! let loc: Locale = "en-US-u-ca-buddhist-t-en-us-h0-hybrid-x-foo"
//! .parse()
//! .expect("Failed to parse.");
//!
//! assert_eq!(loc.id.language, "en".parse().unwrap());
//! assert_eq!(loc.id.script, None);
//! assert_eq!(loc.id.region, Some("US".parse().unwrap()));
//! assert_eq!(loc.id.variants.len(), 0);
//!
//! let key: Key = "ca".parse().expect("Parsing key failed.");
//! let value: Value = "buddhist".parse().expect("Parsing value failed.");
//! assert_eq!(loc.extensions.unicode.keywords.get(&key), Some(&value));
//! ```
//!
//! [`LanguageIdentifier`]: super::LanguageIdentifier
//! [`Locale`]: super::Locale
//! [`subtags`]: super::subtags
//! [`Other Extensions`]: other
//! [`Private Use Extensions`]: private
//! [`Transform Extensions`]: transform
//! [`Unicode Extensions`]: unicode
pub mod other;
pub mod private;
pub mod transform;
pub mod unicode;
use core::cmp::Ordering;
use other::Other;
use private::Private;
use transform::Transform;
use unicode::Unicode;
use alloc::vec::Vec;
use crate::parser::ParserError;
use crate::parser::SubtagIterator;
use crate::subtags;
/// Defines the type of extension.
#[derive(Debug, PartialEq, Eq, Clone, Hash, PartialOrd, Ord, Copy)]
#[non_exhaustive]
pub enum ExtensionType {
/// Transform Extension Type marked as `t`.
Transform,
/// Unicode Extension Type marked as `u`.
Unicode,
/// Private Extension Type marked as `x`.
Private,
/// All other extension types.
Other(u8),
}
impl ExtensionType {
pub(crate) const fn try_from_byte(key: u8) -> Result<Self, ParserError> {
let key = key.to_ascii_lowercase();
match key {
b'u' => Ok(Self::Unicode),
b't' => Ok(Self::Transform),
b'x' => Ok(Self::Private),
b'a'..=b'z' => Ok(Self::Other(key)),
_ => Err(ParserError::InvalidExtension),
}
}
pub(crate) const fn try_from_bytes_manual_slice(
bytes: &[u8],
start: usize,
end: usize,
) -> Result<Self, ParserError> {
if end - start != 1 {
return Err(ParserError::InvalidExtension);
}
#[allow(clippy::indexing_slicing)]
Self::try_from_byte(bytes[start])
}
}
/// A map of extensions associated with a given [`Locale`](crate::Locale).
#[derive(Debug, Default, PartialEq, Eq, Clone, Hash)]
#[non_exhaustive]
pub struct Extensions {
/// A representation of the data for a Unicode extension, when present in the locale identifier.
pub unicode: Unicode,
/// A representation of the data for a transform extension, when present in the locale identifier.
pub transform: Transform,
/// A representation of the data for a private-use extension, when present in the locale identifier.
pub private: Private,
/// A sequence of any other extensions that are present in the locale identifier but are not formally
/// [defined](https://unicode.org/reports/tr35/) and represented explicitly as [`Unicode`], [`Transform`],
/// and [`Private`] are.
pub other: Vec<Other>,
}
impl Extensions {
/// Returns a new empty map of extensions. Same as [`default()`](Default::default()), but is `const`.
///
/// # Examples
///
/// ```
/// use icu::locid::extensions::Extensions;
///
/// assert_eq!(Extensions::new(), Extensions::default());
/// ```
#[inline]
pub const fn new() -> Self {
Self {
unicode: Unicode::new(),
transform: Transform::new(),
private: Private::new(),
other: Vec::new(),
}
}
/// Function to create a new map of extensions containing exactly one unicode extension, callable in `const`
/// context.
#[inline]
pub const fn from_unicode(unicode: Unicode) -> Self {
Self {
unicode,
transform: Transform::new(),
private: Private::new(),
other: Vec::new(),
}
}
/// Returns whether there are no extensions present.
///
/// # Examples
///
/// ```
/// use icu::locid::Locale;
///
/// let loc: Locale = "en-US-u-foo".parse().expect("Parsing failed.");
///
/// assert!(!loc.extensions.is_empty());
/// ```
pub fn is_empty(&self) -> bool {
self.unicode.is_empty()
&& self.transform.is_empty()
&& self.private.is_empty()
&& self.other.is_empty()
}
#[allow(clippy::type_complexity)]
pub(crate) fn as_tuple(
&self,
) -> (
(&unicode::Attributes, &unicode::Keywords),
(
Option<(
subtags::Language,
Option<subtags::Script>,
Option<subtags::Region>,
&subtags::Variants,
)>,
&transform::Fields,
),
&private::Private,
&[other::Other],
) {
(
self.unicode.as_tuple(),
self.transform.as_tuple(),
&self.private,
&self.other,
)
}
/// Returns an ordering suitable for use in [`BTreeSet`].
///
/// The ordering may or may not be equivalent to string ordering, and it
/// may or may not be stable across ICU4X releases.
///
/// [`BTreeSet`]: alloc::collections::BTreeSet
pub fn total_cmp(&self, other: &Self) -> Ordering {
self.as_tuple().cmp(&other.as_tuple())
}
/// Retains the specified extension types, clearing all others.
///
/// # Examples
///
/// ```
/// use icu::locid::extensions::ExtensionType;
/// use icu::locid::Locale;
///
/// let loc: Locale =
/// "und-a-hello-t-mul-u-world-z-zzz-x-extra".parse().unwrap();
///
/// let mut only_unicode = loc.clone();
/// only_unicode
/// .extensions
/// .retain_by_type(|t| t == ExtensionType::Unicode);
/// assert_eq!(only_unicode, "und-u-world".parse().unwrap());
///
/// let mut only_t_z = loc.clone();
/// only_t_z.extensions.retain_by_type(|t| {
/// t == ExtensionType::Transform || t == ExtensionType::Other(b'z')
/// });
/// assert_eq!(only_t_z, "und-t-mul-z-zzz".parse().unwrap());
/// ```
pub fn retain_by_type<F>(&mut self, mut predicate: F)
where
F: FnMut(ExtensionType) -> bool,
{
if !predicate(ExtensionType::Unicode) {
self.unicode.clear();
}
if !predicate(ExtensionType::Transform) {
self.transform.clear();
}
if !predicate(ExtensionType::Private) {
self.private.clear();
}
self.other
.retain(|o| predicate(ExtensionType::Other(o.get_ext_byte())));
}
pub(crate) fn try_from_iter(iter: &mut SubtagIterator) -> Result<Self, ParserError> {
let mut unicode = None;
let mut transform = None;
let mut private = None;
let mut other = Vec::new();
while let Some(subtag) = iter.next() {
if subtag.is_empty() {
return Err(ParserError::InvalidExtension);
}
match subtag.first().map(|b| ExtensionType::try_from_byte(*b)) {
Some(Ok(ExtensionType::Unicode)) => {
if unicode.is_some() {
return Err(ParserError::DuplicatedExtension);
}
unicode = Some(Unicode::try_from_iter(iter)?);
}
Some(Ok(ExtensionType::Transform)) => {
if transform.is_some() {
return Err(ParserError::DuplicatedExtension);
}
transform = Some(Transform::try_from_iter(iter)?);
}
Some(Ok(ExtensionType::Private)) => {
if private.is_some() {
return Err(ParserError::DuplicatedExtension);
}
private = Some(Private::try_from_iter(iter)?);
}
Some(Ok(ExtensionType::Other(ext))) => {
if other.iter().any(|o: &Other| o.get_ext_byte() == ext) {
return Err(ParserError::DuplicatedExtension);
}
let parsed = Other::try_from_iter(ext, iter)?;
if let Err(idx) = other.binary_search(&parsed) {
other.insert(idx, parsed);
} else {
return Err(ParserError::InvalidExtension);
}
}
_ => return Err(ParserError::InvalidExtension),
}
}
Ok(Self {
unicode: unicode.unwrap_or_default(),
transform: transform.unwrap_or_default(),
private: private.unwrap_or_default(),
other,
})
}
pub(crate) fn for_each_subtag_str<E, F>(&self, f: &mut F) -> Result<(), E>
where
F: FnMut(&str) -> Result<(), E>,
{
let mut wrote_tu = false;
// Alphabetic by singleton
self.other.iter().try_for_each(|other| {
if other.get_ext() > 't' && !wrote_tu {
// Since 't' and 'u' are next to each other in alphabetical
// order, write both now.
self.transform.for_each_subtag_str(f)?;
self.unicode.for_each_subtag_str(f)?;
wrote_tu = true;
}
other.for_each_subtag_str(f)?;
Ok(())
})?;
if !wrote_tu {
self.transform.for_each_subtag_str(f)?;
self.unicode.for_each_subtag_str(f)?;
}
// Private must be written last, since it allows single character
// keys. Extensions must also be written in alphabetical order,
// which would seem to imply that other extensions `y` and `z` are
// invalid, but this is not specified.
self.private.for_each_subtag_str(f)?;
Ok(())
}
}
impl_writeable_for_each_subtag_str_no_test!(Extensions);
#[test]
fn test_writeable() {
use crate::Locale;
use writeable::assert_writeable_eq;
assert_writeable_eq!(Extensions::new(), "");
assert_writeable_eq!(
"my-t-my-d0-zawgyi".parse::<Locale>().unwrap().extensions,
"t-my-d0-zawgyi",
);
assert_writeable_eq!(
"ar-SA-u-ca-islamic-civil"
.parse::<Locale>()
.unwrap()
.extensions,
"u-ca-islamic-civil",
);
assert_writeable_eq!(
"en-001-x-foo-bar".parse::<Locale>().unwrap().extensions,
"x-foo-bar",
);
assert_writeable_eq!(
"und-t-m0-true".parse::<Locale>().unwrap().extensions,
"t-m0-true",
);
assert_writeable_eq!(
"und-a-foo-t-foo-u-foo-w-foo-z-foo-x-foo"
.parse::<Locale>()
.unwrap()
.extensions,
"a-foo-t-foo-u-foo-w-foo-z-foo-x-foo",
);
}