From 398b53eed8b7bc1f59fc14c0dab14c67e82b7f4a Mon Sep 17 00:00:00 2001
From: MurakamiShinyu <murakami@vivliostyle.org>
Date: Mon, 5 Feb 2024 16:08:22 +0900
Subject: [PATCH] fix: text-spacing-trim:space-first not working properly in
 some case

- fix #1261
---
 .../core/src/vivliostyle/text-polyfill.ts     | 19 ++++++++++++-------
 1 file changed, 12 insertions(+), 7 deletions(-)

diff --git a/packages/core/src/vivliostyle/text-polyfill.ts b/packages/core/src/vivliostyle/text-polyfill.ts
index b5e7a7fd7..ba13d2412 100644
--- a/packages/core/src/vivliostyle/text-polyfill.ts
+++ b/packages/core/src/vivliostyle/text-polyfill.ts
@@ -446,16 +446,21 @@ class TextSpacingPolyfill {
 
     function checkIfFirstInBlock(): boolean {
       const p = checkPoints[0];
-      let viewNode = p.viewNode;
-      let parent = p.parent;
-      while (parent && parent.inline) {
-        parent = parent.parent;
+      for (let pp = p; ; pp = pp.parent) {
+        if (!pp || !pp.inline) {
+          if (pp?.fragmentIndex !== 1) {
+            // This block is not the first fragment
+            return false;
+          }
+          break;
+        }
       }
-      if (parent?.fragmentIndex !== 1) {
-        return false;
+      if (!p.inline) {
+        // This is at the start of the block
+        return true;
       }
       for (
-        let prev = viewNode.previousSibling;
+        let prev = p.viewNode.previousSibling;
         prev;
         prev = prev.previousSibling
       ) {