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// Copyright 2015 The Servo Project Developers. See the
// COPYRIGHT file at the top-level directory of this distribution.
//
// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
// option. This file may not be copied, modified, or distributed
// except according to those terms.
//! Accessor for `Bidi_Class` property from Unicode Character Database (UCD)
mod tables;
pub use self::tables::{BidiClass, UNICODE_VERSION};
#[cfg(feature = "hardcoded-data")]
use core::char;
#[cfg(feature = "hardcoded-data")]
use core::cmp::Ordering::{Equal, Greater, Less};
#[cfg(feature = "hardcoded-data")]
use self::tables::bidi_class_table;
use crate::data_source::BidiMatchedOpeningBracket;
use crate::BidiClass::*;
#[cfg(feature = "hardcoded-data")]
use crate::BidiDataSource;
/// Hardcoded Bidi data that ships with the unicode-bidi crate.
///
/// This can be enabled with the default `hardcoded-data` Cargo feature.
#[cfg(feature = "hardcoded-data")]
pub struct HardcodedBidiData;
#[cfg(feature = "hardcoded-data")]
impl BidiDataSource for HardcodedBidiData {
fn bidi_class(&self, c: char) -> BidiClass {
bsearch_range_value_table(c, bidi_class_table)
}
}
/// Find the `BidiClass` of a single char.
#[cfg(feature = "hardcoded-data")]
pub fn bidi_class(c: char) -> BidiClass {
bsearch_range_value_table(c, bidi_class_table)
}
/// If this character is a bracket according to BidiBrackets.txt,
/// return the corresponding *normalized* *opening bracket* of the pair,
/// and whether or not it itself is an opening bracket.
pub(crate) fn bidi_matched_opening_bracket(c: char) -> Option<BidiMatchedOpeningBracket> {
for pair in self::tables::bidi_pairs_table {
if pair.0 == c || pair.1 == c {
let skeleton = pair.2.unwrap_or(pair.0);
return Some(BidiMatchedOpeningBracket {
opening: skeleton,
is_open: pair.0 == c,
});
}
}
None
}
pub fn is_rtl(bidi_class: BidiClass) -> bool {
matches!(bidi_class, RLE | RLO | RLI)
}
#[cfg(feature = "hardcoded-data")]
fn bsearch_range_value_table(c: char, r: &'static [(char, char, BidiClass)]) -> BidiClass {
match r.binary_search_by(|&(lo, hi, _)| {
if lo <= c && c <= hi {
Equal
} else if hi < c {
Less
} else {
Greater
}
}) {
Ok(idx) => {
let (_, _, cat) = r[idx];
cat
}
// UCD/extracted/DerivedBidiClass.txt: "All code points not explicitly listed
// for Bidi_Class have the value Left_To_Right (L)."
Err(_) => L,
}
}
#[cfg(all(test, feature = "hardcoded-data"))]
mod tests {
use super::*;
#[test]
fn test_ascii() {
assert_eq!(bidi_class('\u{0000}'), BN);
assert_eq!(bidi_class('\u{0040}'), ON);
assert_eq!(bidi_class('\u{0041}'), L);
assert_eq!(bidi_class('\u{0062}'), L);
assert_eq!(bidi_class('\u{007F}'), BN);
}
#[test]
fn test_bmp() {
// Hebrew
assert_eq!(bidi_class('\u{0590}'), R);
assert_eq!(bidi_class('\u{05D0}'), R);
assert_eq!(bidi_class('\u{05D1}'), R);
assert_eq!(bidi_class('\u{05FF}'), R);
// Arabic
assert_eq!(bidi_class('\u{0600}'), AN);
assert_eq!(bidi_class('\u{0627}'), AL);
assert_eq!(bidi_class('\u{07BF}'), AL);
// Default R + Arabic Extras
assert_eq!(bidi_class('\u{07C0}'), R);
assert_eq!(bidi_class('\u{085F}'), R);
assert_eq!(bidi_class('\u{0860}'), AL);
assert_eq!(bidi_class('\u{0870}'), AL);
assert_eq!(bidi_class('\u{089F}'), NSM);
assert_eq!(bidi_class('\u{08A0}'), AL);
assert_eq!(bidi_class('\u{089F}'), NSM);
assert_eq!(bidi_class('\u{08FF}'), NSM);
// Default ET
assert_eq!(bidi_class('\u{20A0}'), ET);
assert_eq!(bidi_class('\u{20CF}'), ET);
// Arabic Presentation Forms
assert_eq!(bidi_class('\u{FB1D}'), R);
assert_eq!(bidi_class('\u{FB4F}'), R);
assert_eq!(bidi_class('\u{FB50}'), AL);
assert_eq!(bidi_class('\u{FDCF}'), ON);
assert_eq!(bidi_class('\u{FDF0}'), AL);
assert_eq!(bidi_class('\u{FDFF}'), ON);
assert_eq!(bidi_class('\u{FE70}'), AL);
assert_eq!(bidi_class('\u{FEFE}'), AL);
assert_eq!(bidi_class('\u{FEFF}'), BN);
// noncharacters
assert_eq!(bidi_class('\u{FDD0}'), L);
assert_eq!(bidi_class('\u{FDD1}'), L);
assert_eq!(bidi_class('\u{FDEE}'), L);
assert_eq!(bidi_class('\u{FDEF}'), L);
assert_eq!(bidi_class('\u{FFFE}'), L);
assert_eq!(bidi_class('\u{FFFF}'), L);
}
#[test]
fn test_smp() {
// Default AL + R
assert_eq!(bidi_class('\u{10800}'), R);
assert_eq!(bidi_class('\u{10FFF}'), R);
assert_eq!(bidi_class('\u{1E800}'), R);
assert_eq!(bidi_class('\u{1EDFF}'), R);
assert_eq!(bidi_class('\u{1EE00}'), AL);
assert_eq!(bidi_class('\u{1EEFF}'), AL);
assert_eq!(bidi_class('\u{1EF00}'), R);
assert_eq!(bidi_class('\u{1EFFF}'), R);
}
#[test]
fn test_unassigned_planes() {
assert_eq!(bidi_class('\u{30000}'), L);
assert_eq!(bidi_class('\u{40000}'), L);
assert_eq!(bidi_class('\u{50000}'), L);
assert_eq!(bidi_class('\u{60000}'), L);
assert_eq!(bidi_class('\u{70000}'), L);
assert_eq!(bidi_class('\u{80000}'), L);
assert_eq!(bidi_class('\u{90000}'), L);
assert_eq!(bidi_class('\u{a0000}'), L);
}
}