From b60182aade04df6d86277796dce3f4c78898ba96 Mon Sep 17 00:00:00 2001
From: roytam1 <roytam@gmail.com>
Date: Fri, 28 Jun 2024 22:11:08 +0800
Subject: [PATCH] Revert "Revert part of #2492 and replace it with mozilla
 one."

This reverts commit ff8673e87ec444f22cd8b859020b79137a4e35a3.
---
 intl/unicharutil/util/nsUnicodeProperties.cpp | 36 ++++---------------
 intl/unicharutil/util/nsUnicodeProperties.h   | 13 ++++---
 2 files changed, 14 insertions(+), 35 deletions(-)

diff --git a/intl/unicharutil/util/nsUnicodeProperties.cpp b/intl/unicharutil/util/nsUnicodeProperties.cpp
index e78725b036..8a2b04a8b0 100644
--- a/intl/unicharutil/util/nsUnicodeProperties.cpp
+++ b/intl/unicharutil/util/nsUnicodeProperties.cpp
@@ -153,9 +153,7 @@ IsClusterExtender(uint32_t aCh, uint8_t aCategory)
     return ((aCategory >= HB_UNICODE_GENERAL_CATEGORY_SPACING_MARK &&
              aCategory <= HB_UNICODE_GENERAL_CATEGORY_NON_SPACING_MARK) ||
             (aCh >= 0x200c && aCh <= 0x200d) || // ZWJ, ZWNJ
-            (aCh >= 0xff9e && aCh <= 0xff9f) || // katakana sound marks
-            (aCh >= 0x1F3FB && aCh <= 0x1F3FF) || // fitzpatrick skin tone modifiers
-            (aCh >= 0xe0020 && aCh <= 0xe007f)); // emoji (flag) tag characters
+            (aCh >= 0xff9e && aCh <= 0xff9f));  // katakana sound marks
 }
 
 enum HSType {
@@ -226,25 +224,8 @@ ClusterIterator::Next()
         }
     }
 
-    const uint32_t kVS16 = 0xfe0f;
-    const uint32_t kZWJ = 0x200d;
-    // UTF-16 surrogate values for Fitzpatrick type modifiers
-    const uint32_t kFitzpatrickHigh = 0xD83C;
-    const uint32_t kFitzpatrickLowFirst = 0xDFFB;
-    const uint32_t kFitzpatrickLowLast = 0xDFFF;
-
-    bool baseIsEmoji = (GetEmojiPresentation(ch) == EmojiDefault) ||
-                       (GetEmojiPresentation(ch) == TextDefault &&
-                        ((mPos < mLimit && *mPos == kVS16) ||
-                         (mPos + 1 < mLimit &&
-                          *mPos == kFitzpatrickHigh &&
-                          *(mPos + 1) >= kFitzpatrickLowFirst &&
-                          *(mPos + 1) <= kFitzpatrickLowLast)));
-    bool prevWasZwj = false;
-
     while (mPos < mLimit) {
         ch = *mPos;
-        size_t chLen = 1;
 
         // Check for surrogate pairs; note that isolated surrogates will just
         // be treated as generic (non-cluster-extending) characters here,
@@ -252,21 +233,16 @@ ClusterIterator::Next()
         if (NS_IS_HIGH_SURROGATE(ch) && mPos < mLimit - 1 &&
             NS_IS_LOW_SURROGATE(*(mPos + 1))) {
             ch = SURROGATE_TO_UCS4(ch, *(mPos + 1));
-            chLen = 2;
         }
 
-        bool extendCluster = IsClusterExtender(ch) ||
-            (baseIsEmoji && prevWasZwj &&
-                ((GetEmojiPresentation(ch) == EmojiDefault) ||
-                 (GetEmojiPresentation(ch) == TextDefault &&
-                  mPos + chLen < mLimit &&
-                  *(mPos + chLen) == kVS16)));
-        if (!extendCluster) {
+        if (!IsClusterExtender(ch)) {
             break;
         }
 
-        prevWasZwj = (ch == kZWJ);
-        mPos += chLen;
+        mPos++;
+        if (!IS_IN_BMP(ch)) {
+            mPos++;
+        }
     }
 
     NS_ASSERTION(mText < mPos && mPos <= mLimit,
diff --git a/intl/unicharutil/util/nsUnicodeProperties.h b/intl/unicharutil/util/nsUnicodeProperties.h
index eaa066b7f6..38fa230625 100644
--- a/intl/unicharutil/util/nsUnicodeProperties.h
+++ b/intl/unicharutil/util/nsUnicodeProperties.h
@@ -180,14 +180,17 @@ IsDefaultIgnorable(uint32_t aCh)
 inline EmojiPresentation
 GetEmojiPresentation(uint32_t aCh)
 {
-  if (!u_hasBinaryProperty(aCh, UCHAR_EMOJI)) {
-    return TextOnly;
+  if (u_hasBinaryProperty(aCh, UCHAR_EMOJI_COMPONENT)) {
+    return EmojiComponent;
   }
-
-  if (u_hasBinaryProperty(aCh, UCHAR_EMOJI_PRESENTATION)) {
+  if (u_hasBinaryProperty(aCh, UCHAR_EMOJI) &&
+     !u_hasBinaryProperty(aCh, UCHAR_EMOJI_PRESENTATION)) {
+    return TextDefault;
+  }
+  if (u_hasBinaryProperty(aCh, UCHAR_EXTENDED_PICTOGRAPHIC)) {
     return EmojiDefault;
   }
-  return TextDefault;
+  return TextOnly;
 }
 
 // returns the simplified Gen Category as defined in nsIUGenCategory