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
12mod tables;
13
14pub use self::tables::{BidiClass, UNICODE_VERSION};
15#[cfg(feature = "hardcoded-data")]
16use core::char;
17#[cfg(feature = "hardcoded-data")]
18use core::cmp::Ordering::{Equal, Greater, Less};
19
20#[cfg(feature = "hardcoded-data")]
21use self::tables::bidi_class_table;
22use crate::data_source::BidiMatchedOpeningBracket;
23use crate::BidiClass::*;
24#[cfg(feature = "hardcoded-data")]
25use crate::BidiDataSource;
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")]
30pub struct HardcodedBidiData;
31
32#[cfg(feature = "hardcoded-data")]
33impl 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")]
41pub fn bidi_class(c: char) -> BidiClass {
42 bsearch_range_value_table(c, bidi_class_table)
43}
44
45/// If this character is a bracket according to BidiBrackets.txt,
46/// return the corresponding *normalized* *opening bracket* of the pair,
47/// and whether or not it itself is an opening bracket.
48pub(crate) fn bidi_matched_opening_bracket(c: char) -> Option<BidiMatchedOpeningBracket> {
49 for pair: &'static (char, char, Option<…>) in self::tables::bidi_pairs_table {
50 if pair.0 == c || pair.1 == c {
51 let skeleton: char = pair.2.unwrap_or(default:pair.0);
52 return Some(BidiMatchedOpeningBracket {
53 opening: skeleton,
54 is_open: pair.0 == c,
55 });
56 }
57 }
58 None
59}
60
61pub fn is_rtl(bidi_class: BidiClass) -> bool {
62 matches!(bidi_class, RLE | RLO | RLI)
63}
64
65#[cfg(feature = "hardcoded-data")]
66fn bsearch_range_value_table(c: char, r: &'static [(char, char, BidiClass)]) -> BidiClass {
67 match r.binary_search_by(|&(lo: char, hi: char, _)| {
68 if lo <= c && c <= hi {
69 Equal
70 } else if hi < c {
71 Less
72 } else {
73 Greater
74 }
75 }) {
76 Ok(idx: usize) => {
77 let (_, _, cat: BidiClass) = r[idx];
78 cat
79 }
80 // UCD/extracted/DerivedBidiClass.txt: "All code points not explicitly listed
81 // for Bidi_Class have the value Left_To_Right (L)."
82 Err(_) => L,
83 }
84}
85
86#[cfg(all(test, feature = "hardcoded-data"))]
87mod tests {
88 use super::*;
89
90 #[test]
91 fn test_ascii() {
92 assert_eq!(bidi_class('\u{0000}'), BN);
93 assert_eq!(bidi_class('\u{0040}'), ON);
94 assert_eq!(bidi_class('\u{0041}'), L);
95 assert_eq!(bidi_class('\u{0062}'), L);
96 assert_eq!(bidi_class('\u{007F}'), BN);
97 }
98
99 #[test]
100 fn test_bmp() {
101 // Hebrew
102 assert_eq!(bidi_class('\u{0590}'), R);
103 assert_eq!(bidi_class('\u{05D0}'), R);
104 assert_eq!(bidi_class('\u{05D1}'), R);
105 assert_eq!(bidi_class('\u{05FF}'), R);
106
107 // Arabic
108 assert_eq!(bidi_class('\u{0600}'), AN);
109 assert_eq!(bidi_class('\u{0627}'), AL);
110 assert_eq!(bidi_class('\u{07BF}'), AL);
111
112 // Default R + Arabic Extras
113 assert_eq!(bidi_class('\u{07C0}'), R);
114 assert_eq!(bidi_class('\u{085F}'), R);
115 assert_eq!(bidi_class('\u{0860}'), AL);
116 assert_eq!(bidi_class('\u{0870}'), AL);
117 assert_eq!(bidi_class('\u{089F}'), NSM);
118 assert_eq!(bidi_class('\u{08A0}'), AL);
119 assert_eq!(bidi_class('\u{089F}'), NSM);
120 assert_eq!(bidi_class('\u{08FF}'), NSM);
121
122 // Default ET
123 assert_eq!(bidi_class('\u{20A0}'), ET);
124 assert_eq!(bidi_class('\u{20CF}'), ET);
125
126 // Arabic Presentation Forms
127 assert_eq!(bidi_class('\u{FB1D}'), R);
128 assert_eq!(bidi_class('\u{FB4F}'), R);
129 assert_eq!(bidi_class('\u{FB50}'), AL);
130 assert_eq!(bidi_class('\u{FDCF}'), ON);
131 assert_eq!(bidi_class('\u{FDF0}'), AL);
132 assert_eq!(bidi_class('\u{FDFF}'), ON);
133 assert_eq!(bidi_class('\u{FE70}'), AL);
134 assert_eq!(bidi_class('\u{FEFE}'), AL);
135 assert_eq!(bidi_class('\u{FEFF}'), BN);
136
137 // noncharacters
138 assert_eq!(bidi_class('\u{FDD0}'), L);
139 assert_eq!(bidi_class('\u{FDD1}'), L);
140 assert_eq!(bidi_class('\u{FDEE}'), L);
141 assert_eq!(bidi_class('\u{FDEF}'), L);
142 assert_eq!(bidi_class('\u{FFFE}'), L);
143 assert_eq!(bidi_class('\u{FFFF}'), L);
144 }
145
146 #[test]
147 fn test_smp() {
148 // Default AL + R
149 assert_eq!(bidi_class('\u{10800}'), R);
150 assert_eq!(bidi_class('\u{10FFF}'), R);
151 assert_eq!(bidi_class('\u{1E800}'), R);
152 assert_eq!(bidi_class('\u{1EDFF}'), R);
153 assert_eq!(bidi_class('\u{1EE00}'), AL);
154 assert_eq!(bidi_class('\u{1EEFF}'), AL);
155 assert_eq!(bidi_class('\u{1EF00}'), R);
156 assert_eq!(bidi_class('\u{1EFFF}'), R);
157 }
158
159 #[test]
160 fn test_unassigned_planes() {
161 assert_eq!(bidi_class('\u{30000}'), L);
162 assert_eq!(bidi_class('\u{40000}'), L);
163 assert_eq!(bidi_class('\u{50000}'), L);
164 assert_eq!(bidi_class('\u{60000}'), L);
165 assert_eq!(bidi_class('\u{70000}'), L);
166 assert_eq!(bidi_class('\u{80000}'), L);
167 assert_eq!(bidi_class('\u{90000}'), L);
168 assert_eq!(bidi_class('\u{a0000}'), L);
169 }
170}
171