From 3bfb3d37626990819ba66fc5cb26a702235b5de5 Mon Sep 17 00:00:00 2001
From: Jason Harrop <jason@plutext.org>
Date: Mon, 5 Oct 2026 09:13:06 +1100
Subject: [PATCH] FOP-3349: A line that overflows on the float re-layout pass
 is reported, not a NullPointerException

LineLayoutManager.LineBreakingAlgorithm.updateData2 reported an overflowing line through
curChildLM.getFObj(). On the float re-layout pass (PageBreaker.handleFloatLayout) curChildLM is
null, so a line overflowing beside a float wider than the measure threw a NullPointerException and
the document failed. It is now reported against the line manager's own FO, as it already was when
the child had no FO. The code only reports; layout does not change.

Test: float_overflow_relayout.xml, which threw the NullPointerException before.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 .../layoutmgr/inline/LineLayoutManager.java   |  3 +-
 .../float_overflow_relayout.xml               | 46 +++++++++++++++++++
 2 files changed, 48 insertions(+), 1 deletion(-)
 create mode 100644 fop/test/layoutengine/standard-testcases/float_overflow_relayout.xml

diff --git a/fop-core/src/main/java/org/apache/fop/layoutmgr/inline/LineLayoutManager.java b/fop-core/src/main/java/org/apache/fop/layoutmgr/inline/LineLayoutManager.java
index 4477801f2cd..db590bfaa76 100644
--- a/fop-core/src/main/java/org/apache/fop/layoutmgr/inline/LineLayoutManager.java
+++ b/fop-core/src/main/java/org/apache/fop/layoutmgr/inline/LineLayoutManager.java
@@ -400,7 +400,8 @@ public void updateData2(KnuthNode bestActiveNode,
                 InlineLevelEventProducer eventProducer
                     = InlineLevelEventProducer.Provider.get(
                         getFObj().getUserAgent().getEventBroadcaster());
-                if (curChildLM.getFObj() == null) {
+                // curChildLM is null on the float re-layout pass (PageBreaker.handleFloatLayout)
+                if (curChildLM == null || curChildLM.getFObj() == null) {
                     eventProducer.lineOverflows(this, getFObj().getName(), bestActiveNode.line,
                             -lack, getFObj().getLocator());
                 } else {
diff --git a/fop/test/layoutengine/standard-testcases/float_overflow_relayout.xml b/fop/test/layoutengine/standard-testcases/float_overflow_relayout.xml
new file mode 100644
index 00000000000..b013744e4ce
--- /dev/null
+++ b/fop/test/layoutengine/standard-testcases/float_overflow_relayout.xml
@@ -0,0 +1,46 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  Licensed to the Apache Software Foundation (ASF) under one or more
+  contributor license agreements.  See the NOTICE file distributed with
+  this work for additional information regarding copyright ownership.
+  The ASF licenses this file to You under the Apache License, Version 2.0
+  (the "License"); you may not use this file except in compliance with
+  the License.  You may obtain a copy of the License at
+
+       http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+-->
+<!-- $Id$ -->
+<testcase>
+  <info>
+    <p>
+      This test checks a line that overflows beside a float wider than the measure. On the float
+      re-layout pass the line breaking algorithm reported the overflow through curChildLM, which
+      is null there, and FOP threw a NullPointerException instead of reporting it.
+    </p>
+  </info>
+  <fo>
+    <fo:root xmlns:fo="http://www.w3.org/1999/XSL/Format">
+      <fo:layout-master-set>
+        <fo:simple-page-master master-name="page" page-width="595pt" page-height="842pt" margin="85pt">
+          <fo:region-body/>
+        </fo:simple-page-master>
+      </fo:layout-master-set>
+      <fo:page-sequence master-reference="page">
+        <fo:flow flow-name="xsl-region-body">
+          <fo:block><fo:float float="start"><fo:block-container width="480pt" height="200pt"><fo:block> </fo:block></fo:block-container></fo:float></fo:block>
+          <fo:block><fo:block>block child</fo:block><fo:inline>Overflowing ABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZABCDEFGHIJKLMNOPQRSTUVWXYZ</fo:inline></fo:block>
+        </fo:flow>
+      </fo:page-sequence>
+    </fo:root>
+  </fo>
+  <checks>
+    <eval expected="1" xpath="count(//pageViewport)"/>
+    <true xpath="boolean(//word[starts-with(., 'ABCDEFGHIJ')])"/>
+  </checks>
+</testcase>