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 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440 441 442 443 444 445 446 447 448 449 450 451 452 453 454 455 456 457 458 459 460 461 462 463 464 465 466 467 468 469 470 471 472 473 474 475 476 477 478 479 480 481 482 483 484 485 486 487 488 489 490 491 492 493 494 495 496 497 498 499 500 501 502 503 504 505 506 507 508 509 510 511 512 513 514 515 516 517 518 519 520
// 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 ).
//! Access to the Unicode properties or property-based operations that
//! are required for NFC and NFD.
//!
//! Applications should generally use the full normalizers that are
//! provided at the top level of this crate. However, the APIs in this
//! module are provided for callers such as HarfBuzz that specifically
//! want access to the raw canonical composition operation e.g. for use in a
//! glyph-availability-guided custom normalizer.
use crate::char_from_u16;
use crate::error::NormalizerError;
use crate::in_inclusive_range;
use crate::provider::CanonicalCompositionsV1Marker;
use crate::provider::CanonicalDecompositionDataV1Marker;
use crate::provider::CanonicalDecompositionTablesV1Marker;
use crate::provider::NonRecursiveDecompositionSupplementV1Marker;
use crate::trie_value_has_ccc;
use crate::trie_value_indicates_special_non_starter_decomposition;
use crate::BACKWARD_COMBINING_STARTER_MARKER;
use crate::FDFA_MARKER;
use crate::HANGUL_L_BASE;
use crate::HANGUL_N_COUNT;
use crate::HANGUL_S_BASE;
use crate::HANGUL_S_COUNT;
use crate::HANGUL_T_BASE;
use crate::HANGUL_T_COUNT;
use crate::HANGUL_V_BASE;
use crate::NON_ROUND_TRIP_MARKER;
use crate::SPECIAL_NON_STARTER_DECOMPOSITION_MARKER_U16;
/// want access to the underlying properties e.g. for use in a
/// glyph-availability-guided custom normalizer.
use icu_properties::CanonicalCombiningClass;
use icu_provider::prelude::*;
/// The raw canonical composition operation.
///
/// Callers should generally use `ComposingNormalizer` instead of this API.
/// However, this API is provided for callers such as HarfBuzz that specifically
/// want access to the raw canonical composition operation e.g. for use in a
/// glyph-availability-guided custom normalizer.
#[derive(Debug)]
pub struct CanonicalComposition {
canonical_compositions: DataPayload<CanonicalCompositionsV1Marker>,
}
#[cfg(feature = "compiled_data")]
impl Default for CanonicalComposition {
fn default() -> Self {
Self::new()
}
}
impl CanonicalComposition {
/// Performs canonical composition (including Hangul) on a pair of
/// characters or returns `None` if these characters don't compose.
/// Composition exclusions are taken into account.
///
/// # Examples
///
/// ```
/// let comp = icu::normalizer::properties::CanonicalComposition::new();
///
/// assert_eq!(comp.compose('a', 'b'), None); // Just two non-composing starters
/// assert_eq!(comp.compose('a', '\u{0308}'), Some('ä'));
/// assert_eq!(comp.compose('ẹ', '\u{0302}'), Some('ệ'));
/// assert_eq!(comp.compose('𝅗', '𝅥'), None); // Composition exclusion
/// assert_eq!(comp.compose('ে', 'া'), Some('ো')); // Second is starter
/// assert_eq!(comp.compose('ᄀ', 'ᅡ'), Some('가')); // Hangul LV
/// assert_eq!(comp.compose('가', 'ᆨ'), Some('각')); // Hangul LVT
/// ```
#[inline(always)]
pub fn compose(&self, starter: char, second: char) -> Option<char> {
crate::compose(
self.canonical_compositions
.get()
.canonical_compositions
.iter(),
starter,
second,
)
}
/// Constructs a new `CanonicalComposition` using compiled data.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
#[cfg(feature = "compiled_data")]
pub const fn new() -> Self {
Self {
canonical_compositions: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_NORMALIZER_COMP_V1,
),
}
}
icu_provider::gen_any_buffer_data_constructors!(locale: skip, options: skip, error: NormalizerError,
#[cfg(skip)]
functions: [
new,
try_new_with_any_provider,
try_new_with_buffer_provider,
try_new_unstable,
Self,
]
);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::new)]
pub fn try_new_unstable<D>(provider: &D) -> Result<Self, NormalizerError>
where
D: DataProvider<CanonicalCompositionsV1Marker> + ?Sized,
{
let canonical_compositions: DataPayload<CanonicalCompositionsV1Marker> =
provider.load(Default::default())?.take_payload()?;
Ok(CanonicalComposition {
canonical_compositions,
})
}
}
/// The outcome of non-recursive canonical decomposition of a character.
#[allow(clippy::exhaustive_enums)]
#[derive(Debug, PartialEq, Eq)]
pub enum Decomposed {
/// The character is its own canonical decomposition.
Default,
/// The character decomposes to a single different character.
Singleton(char),
/// The character decomposes to two characters.
Expansion(char, char),
}
/// The raw (non-recursive) canonical decomposition operation.
///
/// Callers should generally use `DecomposingNormalizer` instead of this API.
/// However, this API is provided for callers such as HarfBuzz that specifically
/// want access to non-recursive canonical decomposition e.g. for use in a
/// glyph-availability-guided custom normalizer.
#[derive(Debug)]
pub struct CanonicalDecomposition {
decompositions: DataPayload<CanonicalDecompositionDataV1Marker>,
tables: DataPayload<CanonicalDecompositionTablesV1Marker>,
non_recursive: DataPayload<NonRecursiveDecompositionSupplementV1Marker>,
}
#[cfg(feature = "compiled_data")]
impl Default for CanonicalDecomposition {
fn default() -> Self {
Self::new()
}
}
impl CanonicalDecomposition {
/// Performs non-recursive canonical decomposition (including for Hangul).
///
/// ```
/// use icu::normalizer::properties::Decomposed;
/// let decomp = icu::normalizer::properties::CanonicalDecomposition::new();
///
/// assert_eq!(decomp.decompose('e'), Decomposed::Default);
/// assert_eq!(
/// decomp.decompose('ệ'),
/// Decomposed::Expansion('ẹ', '\u{0302}')
/// );
/// assert_eq!(decomp.decompose('각'), Decomposed::Expansion('가', 'ᆨ'));
/// assert_eq!(decomp.decompose('\u{212B}'), Decomposed::Singleton('Å')); // ANGSTROM SIGN
/// assert_eq!(decomp.decompose('\u{2126}'), Decomposed::Singleton('Ω')); // OHM SIGN
/// assert_eq!(decomp.decompose('\u{1F71}'), Decomposed::Singleton('ά')); // oxia
/// ```
#[inline]
pub fn decompose(&self, c: char) -> Decomposed {
let lvt = u32::from(c).wrapping_sub(HANGUL_S_BASE);
if lvt >= HANGUL_S_COUNT {
return self.decompose_non_hangul(c);
}
let t = lvt % HANGUL_T_COUNT;
if t == 0 {
let l = lvt / HANGUL_N_COUNT;
let v = (lvt % HANGUL_N_COUNT) / HANGUL_T_COUNT;
// Safe because values known to be in range
return Decomposed::Expansion(
unsafe { char::from_u32_unchecked(HANGUL_L_BASE + l) },
unsafe { char::from_u32_unchecked(HANGUL_V_BASE + v) },
);
}
let lv = lvt - t;
// Safe because values known to be in range
Decomposed::Expansion(
unsafe { char::from_u32_unchecked(HANGUL_S_BASE + lv) },
unsafe { char::from_u32_unchecked(HANGUL_T_BASE + t) },
)
}
/// Performs non-recursive canonical decomposition except Hangul syllables
/// are reported as `Decomposed::Default`.
#[inline(always)]
fn decompose_non_hangul(&self, c: char) -> Decomposed {
let decomposition = self.decompositions.get().trie.get(c);
if decomposition <= BACKWARD_COMBINING_STARTER_MARKER {
return Decomposed::Default;
}
// The loop is only broken out of as goto forward
#[allow(clippy::never_loop)]
loop {
let trail_or_complex = (decomposition >> 16) as u16;
let lead = decomposition as u16;
if lead > NON_ROUND_TRIP_MARKER && trail_or_complex != 0 {
// Decomposition into two BMP characters: starter and non-starter
if in_inclusive_range(c, '\u{1F71}', '\u{1FFB}') {
// Look in the other trie due to oxia singleton
// mappings to corresponding character with tonos.
break;
}
return Decomposed::Expansion(char_from_u16(lead), char_from_u16(trail_or_complex));
}
if lead > NON_ROUND_TRIP_MARKER {
// Decomposition into one BMP character or non-starter
debug_assert_ne!(
lead, FDFA_MARKER,
"How come we got the U+FDFA NFKD marker here?"
);
if lead == SPECIAL_NON_STARTER_DECOMPOSITION_MARKER_U16 {
// Non-starter
if !in_inclusive_range(c, '\u{0340}', '\u{0F81}') {
return Decomposed::Default;
}
return match c {
'\u{0340}' => {
// COMBINING GRAVE TONE MARK
Decomposed::Singleton('\u{0300}')
}
'\u{0341}' => {
// COMBINING ACUTE TONE MARK
Decomposed::Singleton('\u{0301}')
}
'\u{0343}' => {
// COMBINING GREEK KORONIS
Decomposed::Singleton('\u{0313}')
}
'\u{0344}' => {
// COMBINING GREEK DIALYTIKA TONOS
Decomposed::Expansion('\u{0308}', '\u{0301}')
}
'\u{0F73}' => {
// TIBETAN VOWEL SIGN II
Decomposed::Expansion('\u{0F71}', '\u{0F72}')
}
'\u{0F75}' => {
// TIBETAN VOWEL SIGN UU
Decomposed::Expansion('\u{0F71}', '\u{0F74}')
}
'\u{0F81}' => {
// TIBETAN VOWEL SIGN REVERSED II
Decomposed::Expansion('\u{0F71}', '\u{0F80}')
}
_ => Decomposed::Default,
};
}
return Decomposed::Singleton(char_from_u16(lead));
}
// The recursive decomposition of ANGSTROM SIGN is in the complex
// decomposition structure to avoid a branch in `potential_passthrough`
// for the BMP case.
if c == '\u{212B}' {
// ANGSTROM SIGN
return Decomposed::Singleton('\u{00C5}');
}
// Complex decomposition
// Format for 16-bit value:
// 15..13: length minus two for 16-bit case and length minus one for
// the 32-bit case. Length 8 needs to fit in three bits in
// the 16-bit case, and this way the value is future-proofed
// up to 9 in the 16-bit case. Zero is unused and length one
// in the 16-bit case goes directly into the trie.
// 12: 1 if all trailing characters are guaranteed non-starters,
// 0 if no guarantees about non-starterness.
// Note: The bit choice is this way around to allow for
// dynamically falling back to not having this but instead
// having one more bit for length by merely choosing
// different masks.
// 11..0: Start offset in storage. The offset is to the logical
// sequence of scalars16, scalars32, supplementary_scalars16,
// supplementary_scalars32.
let offset = usize::from(trail_or_complex & 0xFFF);
let tables = self.tables.get();
if offset < tables.scalars16.len() {
if usize::from(trail_or_complex >> 13) != 0 {
// i.e. logical len isn't 2
break;
}
if let Some(first) = tables.scalars16.get(offset) {
if let Some(second) = tables.scalars16.get(offset + 1) {
// Two BMP starters
return Decomposed::Expansion(char_from_u16(first), char_from_u16(second));
}
}
// GIGO case
debug_assert!(false);
return Decomposed::Default;
}
let len = usize::from(trail_or_complex >> 13) + 1;
if len > 2 {
break;
}
let offset24 = offset - tables.scalars16.len();
if let Some(first_c) = tables.scalars24.get(offset24) {
if len == 1 {
if c != first_c {
return Decomposed::Singleton(first_c);
} else {
// Singleton representation used to avoid
// NFC passthrough of characters that combine
// with starters that can occur as the first
// character of an expansion decomposition.
// See section 5 of
// https://www.unicode.org/L2/L2024/24009-utc178-properties-recs.pdf
return Decomposed::Default;
}
}
if let Some(second_c) = tables.scalars24.get(offset24 + 1) {
return Decomposed::Expansion(first_c, second_c);
}
}
// GIGO case
debug_assert!(false);
return Decomposed::Default;
}
let non_recursive = self.non_recursive.get();
let non_recursive_decomposition = non_recursive.trie.get(c);
if non_recursive_decomposition == 0 {
// GIGO case
debug_assert!(false);
return Decomposed::Default;
}
let trail_or_complex = (non_recursive_decomposition >> 16) as u16;
let lead = non_recursive_decomposition as u16;
if lead != 0 && trail_or_complex != 0 {
// Decomposition into two BMP characters
return Decomposed::Expansion(char_from_u16(lead), char_from_u16(trail_or_complex));
}
if lead != 0 {
// Decomposition into one BMP character
return Decomposed::Singleton(char_from_u16(lead));
}
// Decomposition into two non-BMP characters
// Low is offset into a table plus one to keep it non-zero.
let offset = usize::from(trail_or_complex - 1);
if let Some(first) = non_recursive.scalars24.get(offset) {
if let Some(second) = non_recursive.scalars24.get(offset + 1) {
return Decomposed::Expansion(first, second);
}
}
// GIGO case
debug_assert!(false);
Decomposed::Default
}
/// Construct from compiled data.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
#[cfg(feature = "compiled_data")]
pub const fn new() -> Self {
const _: () = assert!(
crate::provider::Baked::SINGLETON_NORMALIZER_NFDEX_V1
.scalars16
.const_len()
+ crate::provider::Baked::SINGLETON_NORMALIZER_NFDEX_V1
.scalars24
.const_len()
<= 0xFFF,
"NormalizerError::FutureExtension"
);
Self {
decompositions: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_NORMALIZER_NFD_V1,
),
tables: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_NORMALIZER_NFDEX_V1,
),
non_recursive: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_NORMALIZER_DECOMP_V1,
),
}
}
icu_provider::gen_any_buffer_data_constructors!(locale: skip, options: skip, error: NormalizerError,
#[cfg(skip)]
functions: [
new,
try_new_with_any_provider,
try_new_with_buffer_provider,
try_new_unstable,
Self,
]
);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::new)]
pub fn try_new_unstable<D>(provider: &D) -> Result<Self, NormalizerError>
where
D: DataProvider<CanonicalDecompositionDataV1Marker>
+ DataProvider<CanonicalDecompositionTablesV1Marker>
+ DataProvider<NonRecursiveDecompositionSupplementV1Marker>
+ ?Sized,
{
let decompositions: DataPayload<CanonicalDecompositionDataV1Marker> =
provider.load(Default::default())?.take_payload()?;
let tables: DataPayload<CanonicalDecompositionTablesV1Marker> =
provider.load(Default::default())?.take_payload()?;
if tables.get().scalars16.len() + tables.get().scalars24.len() > 0xFFF {
// The data is from a future where there exists a normalization flavor whose
// complex decompositions take more than 0xFFF but fewer than 0x1FFF code points
// of space. If a good use case from such a decomposition flavor arises, we can
// dynamically change the bit masks so that the length mask becomes 0x1FFF instead
// of 0xFFF and the all-non-starters mask becomes 0 instead of 0x1000. However,
// since for now the masks are hard-coded, error out.
return Err(NormalizerError::FutureExtension);
}
let non_recursive: DataPayload<NonRecursiveDecompositionSupplementV1Marker> =
provider.load(Default::default())?.take_payload()?;
Ok(CanonicalDecomposition {
decompositions,
tables,
non_recursive,
})
}
}
/// Lookup of the Canonical_Combining_Class Unicode property.
///
/// # Example
///
/// ```
/// use icu::properties::CanonicalCombiningClass;
/// use icu::normalizer::properties::CanonicalCombiningClassMap;
///
/// let map = CanonicalCombiningClassMap::new();
/// assert_eq!(map.get('a'), CanonicalCombiningClass::NotReordered); // U+0061: LATIN SMALL LETTER A
/// assert_eq!(map.get32(0x0301), CanonicalCombiningClass::Above); // U+0301: COMBINING ACUTE ACCENT
/// ```
#[derive(Debug)]
pub struct CanonicalCombiningClassMap {
/// The data trie
decompositions: DataPayload<CanonicalDecompositionDataV1Marker>,
}
#[cfg(feature = "compiled_data")]
impl Default for CanonicalCombiningClassMap {
fn default() -> Self {
Self::new()
}
}
impl CanonicalCombiningClassMap {
/// Look up the canonical combining class for a scalar value
#[inline(always)]
pub fn get(&self, c: char) -> CanonicalCombiningClass {
self.get32(u32::from(c))
}
/// Look up the canonical combining class for a scalar value
/// represented as `u32`. If the argument is outside the scalar
/// value range, `CanonicalCombiningClass::NotReordered` is returned.
pub fn get32(&self, c: u32) -> CanonicalCombiningClass {
let trie_value = self.decompositions.get().trie.get32(c);
if trie_value_has_ccc(trie_value) {
CanonicalCombiningClass(trie_value as u8)
} else if trie_value_indicates_special_non_starter_decomposition(trie_value) {
match c {
0x0340 | 0x0341 | 0x0343 | 0x0344 => CanonicalCombiningClass::Above,
_ => CanonicalCombiningClass::NotReordered,
}
} else {
CanonicalCombiningClass::NotReordered
}
}
/// Construct from compiled data.
///
/// ✨ *Enabled with the `compiled_data` Cargo feature.*
///
/// [📚 Help choosing a constructor](icu_provider::constructors)
#[cfg(feature = "compiled_data")]
pub const fn new() -> Self {
CanonicalCombiningClassMap {
decompositions: DataPayload::from_static_ref(
crate::provider::Baked::SINGLETON_NORMALIZER_NFD_V1,
),
}
}
icu_provider::gen_any_buffer_data_constructors!(locale: skip, options: skip, error: NormalizerError,
#[cfg(skip)]
functions: [
new,
try_new_with_any_provider,
try_new_with_buffer_provider,
try_new_unstable,
Self,
]);
#[doc = icu_provider::gen_any_buffer_unstable_docs!(UNSTABLE, Self::new)]
pub fn try_new_unstable<D>(provider: &D) -> Result<Self, NormalizerError>
where
D: DataProvider<CanonicalDecompositionDataV1Marker> + ?Sized,
{
let decompositions: DataPayload<CanonicalDecompositionDataV1Marker> =
provider.load(Default::default())?.take_payload()?;
Ok(CanonicalCombiningClassMap { decompositions })
}
}