From 01b2ed4706f658bd3ddf2b4b03e14c895fde00c4 Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Thu, 18 Jun 2026 13:22:22 +0100
Subject: [PATCH 1/2] fix: keep a hard break before an attention run
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When a hard break was immediately followed by an attention run (emphasis or
strong) whose inner side is whitespace, the break was turned into text on a
round-trip:

    {type: 'paragraph', children: [
      {type: 'break'},
      {type: 'strong', children: [{type: 'text', value: ' x'}]}
    ]}

serialized to `\&#xA;**&#x20;x**`, where the break’s line ending was
character-referenced. The attention run asks to encode the character on its
outer side (here whitespace, to keep the run forming), and that character
happened to be the `\n` of the break, so the break was destroyed.

A line ending can never fuse with the following run — the run starts on a
new line — so skip the surrounding encoding when the preceding character is
a line ending.
---
 lib/util/container-phrasing.js |  6 +++++-
 test/index.js                  | 16 ++++++++++++++++
 2 files changed, 21 insertions(+), 1 deletion(-)

diff --git a/lib/util/container-phrasing.js b/lib/util/container-phrasing.js
index 3b4dc46..4f9c4c2 100644
--- a/lib/util/container-phrasing.js
+++ b/lib/util/container-phrasing.js
@@ -104,7 +104,11 @@ export function containerPhrasing(parent, state, info) {
       if (
         results.length > 0 &&
         encodingInfo.before &&
-        before === results[results.length - 1].slice(-1)
+        before === results[results.length - 1].slice(-1) &&
+        // A line ending (such as a hard break) is structural: encoding it would
+        // break the break, and it can’t fuse with the following attention run.
+        before !== '\n' &&
+        before !== '\r'
       ) {
         results[results.length - 1] =
           results[results.length - 1].slice(0, -1) +
diff --git a/test/index.js b/test/index.js
index e47facd..24a75d9 100644
--- a/test/index.js
+++ b/test/index.js
@@ -746,6 +746,22 @@ test('break', async function (t) {
     assert.equal(to({type: 'break'}), '\\\n')
   })
 
+  await t.test(
+    'should not character-reference a break before an attention run',
+    async function () {
+      assert.equal(
+        to({
+          type: 'paragraph',
+          children: [
+            {type: 'break'},
+            {type: 'strong', children: [{type: 'text', value: ' x'}]}
+          ]
+        }),
+        '\\\n**&#x20;x**\n'
+      )
+    }
+  )
+
   await t.test(
     'should serialize breaks in heading (atx) as a space',
     async function () {

From a88d00173b37ef79fbf5efb84e2f5da75713c031 Mon Sep 17 00:00:00 2001
From: Yarchik <spoko.dev@gmail.com>
Date: Mon, 22 Jun 2026 18:32:45 +0100
Subject: [PATCH 2/2] Remove explanatory comments

---
 lib/util/container-phrasing.js | 2 --
 1 file changed, 2 deletions(-)

diff --git a/lib/util/container-phrasing.js b/lib/util/container-phrasing.js
index 4f9c4c2..21a039c 100644
--- a/lib/util/container-phrasing.js
+++ b/lib/util/container-phrasing.js
@@ -105,8 +105,6 @@ export function containerPhrasing(parent, state, info) {
         results.length > 0 &&
         encodingInfo.before &&
         before === results[results.length - 1].slice(-1) &&
-        // A line ending (such as a hard break) is structural: encoding it would
-        // break the break, and it can’t fuse with the following attention run.
         before !== '\n' &&
         before !== '\r'
       ) {