[TextServer] Track emoji subruns separately from parentheses stack.

modules/text_server_adv/script_iterator.cpp

@@ -56,6 +56,11 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 		UScriptCode script_code;
 	};
 
+	struct EmojiSubrunEntry {
+		int start;
+		int end;
+	};
+
 	if (p_start >= p_length) {
 		p_start = p_length - 1;
 	}
@@ -65,8 +70,12 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 	}
 
 	int paren_size = PAREN_STACK_DEPTH;
-	ParenStackEntry starter_stack[PAREN_STACK_DEPTH];
+	ParenStackEntry starter_paren_stack[PAREN_STACK_DEPTH];
-	ParenStackEntry *paren_stack = starter_stack;
+	ParenStackEntry *paren_stack = starter_paren_stack;
+
+	int emoji_size = EMOJI_STACK_DEPTH;
+	EmojiSubrunEntry starter_emoji_stack[EMOJI_STACK_DEPTH];
+	EmojiSubrunEntry *emoji_stack = starter_emoji_stack;
 
 	int script_start;
 	int script_end = p_start;
@@ -78,19 +87,38 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 
 	do {
 		script_code = USCRIPT_COMMON;
+		int emoji_sp = -1;
+		bool emoji_run = false;
 		for (script_start = script_end; script_end < p_length; script_end++) {
 			UChar32 ch = str[script_end];
 			UChar32 n = (script_end + 1 < p_length) ? str[script_end + 1] : 0;
+			if (is_emoji(ch, n)) {
+				if (!emoji_run) {
+					emoji_run = true;
+					emoji_sp++;
+					if (unlikely(emoji_sp >= emoji_size)) {
+						emoji_size += EMOJI_STACK_DEPTH;
+						if (emoji_stack == starter_emoji_stack) {
+							emoji_stack = static_cast<EmojiSubrunEntry *>(memalloc(emoji_size * sizeof(EmojiSubrunEntry)));
+						} else {
+							emoji_stack = static_cast<EmojiSubrunEntry *>(memrealloc(emoji_stack, emoji_size * sizeof(EmojiSubrunEntry)));
+						}
+					}
+					emoji_stack[emoji_sp].start = script_end;
+					emoji_stack[emoji_sp].end = script_end;
+				}
+			} else if (emoji_run && ch != ZERO_WIDTH_JOINER && ch != VARIATION_SELECTOR_16 && !(u_hasBinaryProperty(ch, UCHAR_EXTENDED_PICTOGRAPHIC) && n != VARIATION_SELECTOR_15)) {
+				emoji_run = false;
+				emoji_stack[emoji_sp].end = script_end;
+			}
+
 			UScriptCode sc = uscript_getScript(ch, &err);
 			if (U_FAILURE(err)) {
-				if (paren_stack != starter_stack) {
+				if (paren_stack != starter_paren_stack) {
 					memfree(paren_stack);
 				}
 				ERR_FAIL_MSG(u_errorName(err));
 			}
-			if (is_emoji(ch, n)) {
-				sc = USCRIPT_SYMBOLS_EMOJI;
-			}
 
 			if (u_getIntPropertyValue(ch, UCHAR_BIDI_PAIRED_BRACKET_TYPE) != U_BPT_NONE) {
 				if (u_getIntPropertyValue(ch, UCHAR_BIDI_PAIRED_BRACKET_TYPE) == U_BPT_OPEN) {
@@ -99,7 +127,7 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 					if (unlikely(paren_sp >= paren_size)) {
 						// If the stack is full, allocate more space to handle deeply nested parentheses. This is unlikely to happen with any real text.
 						paren_size += PAREN_STACK_DEPTH;
-						if (paren_stack == starter_stack) {
+						if (paren_stack == starter_paren_stack) {
 							paren_stack = static_cast<ParenStackEntry *>(memalloc(paren_size * sizeof(ParenStackEntry)));
 						} else {
 							paren_stack = static_cast<ParenStackEntry *>(memrealloc(paren_stack, paren_size * sizeof(ParenStackEntry)));
@@ -122,11 +150,7 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 				}
 			}
 
-			if (script_code == USCRIPT_SYMBOLS_EMOJI && script_code != sc) {
+			if (same_script(script_code, sc)) {
-				if (ch == VARIATION_SELECTOR_15 || n == VARIATION_SELECTOR_15 || !(is_emoji(ch, n) || ch == ZERO_WIDTH_JOINER || ch == VARIATION_SELECTOR_16 || u_hasBinaryProperty(ch, UCHAR_EXTENDED_PICTOGRAPHIC))) {
-					break;
-				}
-			} else if (same_script(script_code, sc)) {
 				if (script_code <= USCRIPT_INHERITED && sc > USCRIPT_INHERITED) {
 					script_code = sc;
 					// Now that we have a final script code, fix any open characters we pushed before we knew the script code.
@@ -145,16 +169,40 @@ ScriptIterator::ScriptIterator(const String &p_string, int p_start, int p_length
 				break;
 			}
 		}
+		if (emoji_run) {
+			emoji_stack[emoji_sp].end = script_end;
+		}
 
+		for (int sub = 0; sub <= emoji_sp; sub++) {
+			if (emoji_stack[sub].start > script_start) {
+				ScriptRange rng;
+				rng.script = hb_icu_script_to_script(script_code);
+				rng.start = script_start;
+				rng.end = emoji_stack[sub].start;
+				script_ranges.push_back(rng);
+			}
+			ScriptRange rng;
+			rng.script = (hb_script_t)HB_TAG('Z', 's', 'y', 'e');
+			rng.start = emoji_stack[sub].start;
+			rng.end = emoji_stack[sub].end;
+			script_ranges.push_back(rng);
+
+			script_start = emoji_stack[sub].end;
+		}
+		if (script_start != script_end) {
 			ScriptRange rng;
 			rng.script = hb_icu_script_to_script(script_code);
 			rng.start = script_start;
 			rng.end = script_end;
-
 			script_ranges.push_back(rng);
+		}
+
+		if (emoji_stack != starter_emoji_stack) {
+			memfree(emoji_stack);
+		}
 	} while (script_end < p_length);
 
-	if (paren_stack != starter_stack) {
+	if (paren_stack != starter_paren_stack) {
 		memfree(paren_stack);
 	}
 }

modules/text_server_adv/script_iterator.h

@@ -58,6 +58,7 @@ using namespace godot;
 
 class ScriptIterator {
 	static const int PAREN_STACK_DEPTH = 128;
+	static const int EMOJI_STACK_DEPTH = 32;
 
 public:
 	struct ScriptRange {