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-rw-r--r--vendor/unicode-normalization/src/recompose.rs169
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diff --git a/vendor/unicode-normalization/src/recompose.rs b/vendor/unicode-normalization/src/recompose.rs
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+// Copyright 2012-2015 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 <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.
+
+use crate::decompose::Decompositions;
+use core::{
+ fmt::{self, Write},
+ iter::FusedIterator,
+};
+use tinyvec::TinyVec;
+
+#[derive(Clone)]
+enum RecompositionState {
+ Composing,
+ Purging(usize),
+ Finished(usize),
+}
+
+/// External iterator for a string recomposition's characters.
+#[derive(Clone)]
+pub struct Recompositions<I> {
+ iter: Decompositions<I>,
+ state: RecompositionState,
+ buffer: TinyVec<[char; 4]>,
+ composee: Option<char>,
+ last_ccc: Option<u8>,
+}
+
+impl<I: Iterator<Item = char>> Recompositions<I> {
+ /// Create a new recomposition iterator for canonical compositions (NFC)
+ ///
+ /// Note that this iterator can also be obtained by directly calling [`.nfc()`](crate::UnicodeNormalization::nfc)
+ /// on the iterator.
+ #[inline]
+ pub fn new_canonical(iter: I) -> Self {
+ Recompositions {
+ iter: Decompositions::new_canonical(iter),
+ state: self::RecompositionState::Composing,
+ buffer: TinyVec::new(),
+ composee: None,
+ last_ccc: None,
+ }
+ }
+
+ /// Create a new recomposition iterator for compatability compositions (NFkC)
+ ///
+ /// Note that this iterator can also be obtained by directly calling [`.nfkc()`](crate::UnicodeNormalization::nfkc)
+ /// on the iterator.
+ #[inline]
+ pub fn new_compatible(iter: I) -> Self {
+ Recompositions {
+ iter: Decompositions::new_compatible(iter),
+ state: self::RecompositionState::Composing,
+ buffer: TinyVec::new(),
+ composee: None,
+ last_ccc: None,
+ }
+ }
+}
+
+impl<I: Iterator<Item = char>> Iterator for Recompositions<I> {
+ type Item = char;
+
+ #[inline]
+ fn next(&mut self) -> Option<char> {
+ use self::RecompositionState::*;
+
+ loop {
+ match self.state {
+ Composing => {
+ for ch in self.iter.by_ref() {
+ let ch_class = super::char::canonical_combining_class(ch);
+ let k = match self.composee {
+ None => {
+ if ch_class != 0 {
+ return Some(ch);
+ }
+ self.composee = Some(ch);
+ continue;
+ }
+ Some(k) => k,
+ };
+ match self.last_ccc {
+ None => match super::char::compose(k, ch) {
+ Some(r) => {
+ self.composee = Some(r);
+ continue;
+ }
+ None => {
+ if ch_class == 0 {
+ self.composee = Some(ch);
+ return Some(k);
+ }
+ self.buffer.push(ch);
+ self.last_ccc = Some(ch_class);
+ }
+ },
+ Some(l_class) => {
+ if l_class >= ch_class {
+ // `ch` is blocked from `composee`
+ if ch_class == 0 {
+ self.composee = Some(ch);
+ self.last_ccc = None;
+ self.state = Purging(0);
+ return Some(k);
+ }
+ self.buffer.push(ch);
+ self.last_ccc = Some(ch_class);
+ continue;
+ }
+ match super::char::compose(k, ch) {
+ Some(r) => {
+ self.composee = Some(r);
+ continue;
+ }
+ None => {
+ self.buffer.push(ch);
+ self.last_ccc = Some(ch_class);
+ }
+ }
+ }
+ }
+ }
+ self.state = Finished(0);
+ if self.composee.is_some() {
+ return self.composee.take();
+ }
+ }
+ Purging(next) => match self.buffer.get(next).cloned() {
+ None => {
+ self.buffer.clear();
+ self.state = Composing;
+ }
+ s => {
+ self.state = Purging(next + 1);
+ return s;
+ }
+ },
+ Finished(next) => match self.buffer.get(next).cloned() {
+ None => {
+ self.buffer.clear();
+ return self.composee.take();
+ }
+ s => {
+ self.state = Finished(next + 1);
+ return s;
+ }
+ },
+ }
+ }
+ }
+}
+
+impl<I: Iterator<Item = char> + FusedIterator> FusedIterator for Recompositions<I> {}
+
+impl<I: Iterator<Item = char> + Clone> fmt::Display for Recompositions<I> {
+ fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+ for c in self.clone() {
+ f.write_char(c)?;
+ }
+ Ok(())
+ }
+}