vendor/unicode-bidi/src/char_data/mod.rs

   1 // Copyright 2015 The Servo Project Developers. See the
   2 // COPYRIGHT file at the top-level directory of this distribution.
   3 //
   4 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   5 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   6 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   7 // option. This file may not be copied, modified, or distributed
   8 // except according to those terms.
   9
  10 //! Accessor for `Bidi_Class` property from Unicode Character Database (UCD)
  11
  12 mod tables;
  13
  14 pub use self::tables::{BidiClass, UNICODE_VERSION};
  15 #[cfg(feature = "hardcoded-data")]
  16 use core::char;
  17 #[cfg(feature = "hardcoded-data")]
  18 use core::cmp::Ordering::{Equal, Greater, Less};
  19
  20 #[cfg(feature = "hardcoded-data")]
  21 use self::tables::bidi_class_table;
  22 use crate::BidiClass::*;
  23 #[cfg(feature = "hardcoded-data")]
  24 use crate::BidiDataSource;
  25
  26 /// Hardcoded Bidi data that ships with the unicode-bidi crate.
  27 ///
  28 /// This can be enabled with the default `hardcoded-data` Cargo feature.
  29 #[cfg(feature = "hardcoded-data")]
  30 pub struct HardcodedBidiData;
  31
  32 #[cfg(feature = "hardcoded-data")]
  33 impl BidiDataSource for HardcodedBidiData {
  34     fn bidi_class(&self, c: char) -> BidiClass {
  35         bsearch_range_value_table(c, bidi_class_table)
  36     }
  37 }
  38
  39 /// Find the `BidiClass` of a single char.
  40 #[cfg(feature = "hardcoded-data")]
  41 pub fn bidi_class(c: char) -> BidiClass {
  42     bsearch_range_value_table(c, bidi_class_table)
  43 }
  44
  45 pub fn is_rtl(bidi_class: BidiClass) -> bool {
  46     match bidi_class {
  47         RLE | RLO | RLI => true,
  48         _ => false,
  49     }
  50 }
  51
  52 #[cfg(feature = "hardcoded-data")]
  53 fn bsearch_range_value_table(c: char, r: &'static [(char, char, BidiClass)]) -> BidiClass {
  54     match r.binary_search_by(|&(lo, hi, _)| {
  55         if lo <= c && c <= hi {
  56             Equal
  57         } else if hi < c {
  58             Less
  59         } else {
  60             Greater
  61         }
  62     }) {
  63         Ok(idx) => {
  64             let (_, _, cat) = r[idx];
  65             cat
  66         }
  67         // UCD/extracted/DerivedBidiClass.txt: "All code points not explicitly listed
  68         // for Bidi_Class have the value Left_To_Right (L)."
  69         Err(_) => L,
  70     }
  71 }
  72
  73 #[cfg(all(test, feature = "hardcoded-data"))]
  74 mod tests {
  75     use super::*;
  76
  77     #[test]
  78     fn test_ascii() {
  79         assert_eq!(bidi_class('\u{0000}'), BN);
  80         assert_eq!(bidi_class('\u{0040}'), ON);
  81         assert_eq!(bidi_class('\u{0041}'), L);
  82         assert_eq!(bidi_class('\u{0062}'), L);
  83         assert_eq!(bidi_class('\u{007F}'), BN);
  84     }
  85
  86     #[test]
  87     fn test_bmp() {
  88         // Hebrew
  89         assert_eq!(bidi_class('\u{0590}'), R);
  90         assert_eq!(bidi_class('\u{05D0}'), R);
  91         assert_eq!(bidi_class('\u{05D1}'), R);
  92         assert_eq!(bidi_class('\u{05FF}'), R);
  93
  94         // Arabic
  95         assert_eq!(bidi_class('\u{0600}'), AN);
  96         assert_eq!(bidi_class('\u{0627}'), AL);
  97         assert_eq!(bidi_class('\u{07BF}'), AL);
  98
  99         // Default R + Arabic Extras
 100         assert_eq!(bidi_class('\u{07C0}'), R);
 101         assert_eq!(bidi_class('\u{085F}'), R);
 102         assert_eq!(bidi_class('\u{0860}'), AL);
 103         assert_eq!(bidi_class('\u{0870}'), AL);
 104         assert_eq!(bidi_class('\u{089F}'), NSM);
 105         assert_eq!(bidi_class('\u{08A0}'), AL);
 106         assert_eq!(bidi_class('\u{089F}'), NSM);
 107         assert_eq!(bidi_class('\u{08FF}'), NSM);
 108
 109         // Default ET
 110         assert_eq!(bidi_class('\u{20A0}'), ET);
 111         assert_eq!(bidi_class('\u{20CF}'), ET);
 112
 113         // Arabic Presentation Forms
 114         assert_eq!(bidi_class('\u{FB1D}'), R);
 115         assert_eq!(bidi_class('\u{FB4F}'), R);
 116         assert_eq!(bidi_class('\u{FB50}'), AL);
 117         assert_eq!(bidi_class('\u{FDCF}'), ON);
 118         assert_eq!(bidi_class('\u{FDF0}'), AL);
 119         assert_eq!(bidi_class('\u{FDFF}'), ON);
 120         assert_eq!(bidi_class('\u{FE70}'), AL);
 121         assert_eq!(bidi_class('\u{FEFE}'), AL);
 122         assert_eq!(bidi_class('\u{FEFF}'), BN);
 123
 124         // noncharacters
 125         assert_eq!(bidi_class('\u{FDD0}'), L);
 126         assert_eq!(bidi_class('\u{FDD1}'), L);
 127         assert_eq!(bidi_class('\u{FDEE}'), L);
 128         assert_eq!(bidi_class('\u{FDEF}'), L);
 129         assert_eq!(bidi_class('\u{FFFE}'), L);
 130         assert_eq!(bidi_class('\u{FFFF}'), L);
 131     }
 132
 133     #[test]
 134     fn test_smp() {
 135         // Default AL + R
 136         assert_eq!(bidi_class('\u{10800}'), R);
 137         assert_eq!(bidi_class('\u{10FFF}'), R);
 138         assert_eq!(bidi_class('\u{1E800}'), R);
 139         assert_eq!(bidi_class('\u{1EDFF}'), R);
 140         assert_eq!(bidi_class('\u{1EE00}'), AL);
 141         assert_eq!(bidi_class('\u{1EEFF}'), AL);
 142         assert_eq!(bidi_class('\u{1EF00}'), R);
 143         assert_eq!(bidi_class('\u{1EFFF}'), R);
 144     }
 145
 146     #[test]
 147     fn test_unassigned_planes() {
 148         assert_eq!(bidi_class('\u{30000}'), L);
 149         assert_eq!(bidi_class('\u{40000}'), L);
 150         assert_eq!(bidi_class('\u{50000}'), L);
 151         assert_eq!(bidi_class('\u{60000}'), L);
 152         assert_eq!(bidi_class('\u{70000}'), L);
 153         assert_eq!(bidi_class('\u{80000}'), L);
 154         assert_eq!(bidi_class('\u{90000}'), L);
 155         assert_eq!(bidi_class('\u{a0000}'), L);
 156     }
 157 }