From 6a489c7e89085f8c953478a813e9f8bab9f8cc1b Mon Sep 17 00:00:00 2001
From: Henri Sivonen <hsivonen@hsivonen.fi>
Date: Thu, 19 Sep 2024 20:13:22 +0300
Subject: [PATCH] Make the GBK-range GB18030-2022 changes work

---
 src/gb18030.rs      | 16 ++++++++++----
 src/gb18030_2022.rs | 54 +++++++++++++++++++++++++++++++++++++++++++++
 src/lib.rs          |  1 +
 3 files changed, 67 insertions(+), 4 deletions(-)
 create mode 100644 src/gb18030_2022.rs

diff --git a/src/gb18030.rs b/src/gb18030.rs
index a0b3bd7f..515d0e80 100644
--- a/src/gb18030.rs
+++ b/src/gb18030.rs
@@ -9,6 +9,7 @@
 
 use super::*;
 use crate::data::*;
+use crate::gb18030_2022::*;
 use crate::handles::*;
 use crate::variant::*;
 // Rust 1.14.0 requires the following despite the asterisk above.
@@ -347,8 +348,15 @@ fn gbk_encode_non_unified(bmp: u16) -> Option<(usize, usize)> {
         }
         return None;
     }
-    if bmp >= 0xE794 {
-        // Various brackets, all in PUA or full-width regions
+
+    if in_inclusive_range16(bmp, 0xE78D, 0xE864) {
+        // The array is sorted but short, so let's do linear search.
+        if let Some(pos) = position(&GB18030_2022_OVERRIDE_PUA[..], bmp) {
+            let pair = &GB18030_2022_OVERRIDE_BYTES[pos];
+            return Some((pair[0].into(), pair[1].into()));
+        }
+    } else if bmp >= 0xFE17 {
+        // Various brackets, all in full-width regions
         if let Some(pos) = position(&GB2312_SYMBOLS_AFTER_GREEK[..], bmp) {
             return Some((0xA6, pos + (0x9F - 0x60 + 0xA1)));
         }
@@ -380,8 +388,8 @@ fn gbk_encode_non_unified(bmp: u16) -> Option<(usize, usize)> {
         let offset = if other_trail < 0x3F { 0x40 } else { 0x41 };
         return Some((other_lead + (0x81 + 0x20), other_trail + offset));
     }
-    // CJK Radicals Supplement or PUA in GBK_BOTTOM
-    if in_inclusive_range16(bmp, 0x2E81, 0x2ECA) || in_inclusive_range16(bmp, 0xE816, 0xE864) {
+    // CJK Radicals Supplement and U+9FBx ideographs in GBK_BOTTOM
+    if in_inclusive_range16(bmp, 0x2E81, 0x2ECA) || in_inclusive_range16(bmp, 0x9FB4, 0x9FBB) {
         if let Some(pos) = position(&GBK_BOTTOM[21..], bmp) {
             let trail = pos + 16;
             let offset = if trail < 0x3F { 0x40 } else { 0x41 };
diff --git a/src/gb18030_2022.rs b/src/gb18030_2022.rs
new file mode 100644
index 00000000..3163f56a
--- /dev/null
+++ b/src/gb18030_2022.rs
@@ -0,0 +1,54 @@
+// Copyright © WHATWG (Apple, Google, Mozilla, Microsoft).
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+// 1. Redistributions of source code must retain the above copyright notice, this
+//    list of conditions and the following disclaimer.
+//
+// 2. Redistributions in binary form must reproduce the above copyright notice,
+//    this list of conditions and the following disclaimer in the documentation
+//    and/or other materials provided with the distribution.
+//
+// 3. Neither the name of the copyright holder nor the names of its
+//    contributors may be used to endorse or promote products derived from
+//    this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+// DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
+// FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+// DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+// SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
+// CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+// OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+/// The PUA code points special-cased in the GB18030 encoder.
+pub(crate) static GB18030_2022_OVERRIDE_PUA: [u16; 18] = [
+    0xE78D, 0xE78E, 0xE78F, 0xE790, 0xE791, 0xE792, 0xE793, 0xE794, 0xE795, 0xE796, 0xE81E, 0xE826,
+    0xE82B, 0xE82C, 0xE832, 0xE843, 0xE854, 0xE864,
+];
+
+/// The bytes corresponding to the PUA code points special-cased in the GB18030 encoder.
+pub(crate) static GB18030_2022_OVERRIDE_BYTES: [[u8; 2]; 18] = [
+    [0xA6, 0xD9],
+    [0xA6, 0xDA],
+    [0xA6, 0xDB],
+    [0xA6, 0xDC],
+    [0xA6, 0xDD],
+    [0xA6, 0xDE],
+    [0xA6, 0xDF],
+    [0xA6, 0xEC],
+    [0xA6, 0xED],
+    [0xA6, 0xF3],
+    [0xFE, 0x59],
+    [0xFE, 0x61],
+    [0xFE, 0x66],
+    [0xFE, 0x67],
+    [0xFE, 0x6D],
+    [0xFE, 0x7E],
+    [0xFE, 0x90],
+    [0xFE, 0xA0],
+];
diff --git a/src/lib.rs b/src/lib.rs
index b708b704..d4b92d61 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -761,6 +761,7 @@ mod big5;
 mod euc_jp;
 mod euc_kr;
 mod gb18030;
+mod gb18030_2022;
 mod iso_2022_jp;
 mod replacement;
 mod shift_jis;