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authorMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
committerMatt A. Tobin <mattatobin@localhost.localdomain>2018-02-02 04:16:08 -0500
commit5f8de423f190bbb79a62f804151bc24824fa32d8 (patch)
tree10027f336435511475e392454359edea8e25895d /third_party/rust/unicode-normalization/src/recompose.rs
parent49ee0794b5d912db1f95dce6eb52d781dc210db5 (diff)
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Add m-esr52 at 52.6.0
Diffstat (limited to 'third_party/rust/unicode-normalization/src/recompose.rs')
-rw-r--r--third_party/rust/unicode-normalization/src/recompose.rs137
1 files changed, 137 insertions, 0 deletions
diff --git a/third_party/rust/unicode-normalization/src/recompose.rs b/third_party/rust/unicode-normalization/src/recompose.rs
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+++ b/third_party/rust/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 std::collections::VecDeque;
+use decompose::Decompositions;
+
+#[derive(Clone)]
+enum RecompositionState {
+ Composing,
+ Purging,
+ Finished
+}
+
+/// External iterator for a string recomposition's characters.
+#[derive(Clone)]
+pub struct Recompositions<I> {
+ iter: Decompositions<I>,
+ state: RecompositionState,
+ buffer: VecDeque<char>,
+ composee: Option<char>,
+ last_ccc: Option<u8>
+}
+
+#[inline]
+pub fn new_canonical<I: Iterator<Item=char>>(iter: I) -> Recompositions<I> {
+ Recompositions {
+ iter: super::decompose::new_canonical(iter),
+ state: self::RecompositionState::Composing,
+ buffer: VecDeque::new(),
+ composee: None,
+ last_ccc: None,
+ }
+}
+
+#[inline]
+pub fn new_compatible<I: Iterator<Item=char>>(iter: I) -> Recompositions<I> {
+ Recompositions {
+ iter: super::decompose::new_compatible(iter),
+ state : self::RecompositionState::Composing,
+ buffer: VecDeque::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);
+ if self.composee.is_none() {
+ if ch_class != 0 {
+ return Some(ch);
+ }
+ self.composee = Some(ch);
+ continue;
+ }
+ let k = self.composee.clone().unwrap();
+
+ 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_back(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;
+ return Some(k);
+ }
+ self.buffer.push_back(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_back(ch);
+ self.last_ccc = Some(ch_class);
+ }
+ }
+ }
+ }
+ }
+ self.state = Finished;
+ if self.composee.is_some() {
+ return self.composee.take();
+ }
+ }
+ Purging => {
+ match self.buffer.pop_front() {
+ None => self.state = Composing,
+ s => return s
+ }
+ }
+ Finished => {
+ match self.buffer.pop_front() {
+ None => return self.composee.take(),
+ s => return s
+ }
+ }
+ }
+ }
+ }
+}