From 6c7bf59087e720a663fc5aec7ec5b2d502d7accd Mon Sep 17 00:00:00 2001
From: PJ Fanning <fanningpj@apache.org>
Date: Wed, 9 Sep 2020 07:05:09 +0000
Subject: [PATCH] [bug-64721] NullPointerException occurs when calling
 getDataSize() of an object created with ExtRst.copy(). Thanks to Kwon Ohyoung

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1881582 13f79535-47bb-0310-9956-ffa450edef68
---
 build.gradle                                  |  4 +-
 .../apache/poi/hssf/record/common/ExtRst.java |  1 +
 .../hssf/record/common/TestUnicodeString.java | 54 +++++++++++++++++++
 3 files changed, 57 insertions(+), 2 deletions(-)

diff --git a/build.gradle b/build.gradle
index b8628215e3..fe6b24eff2 100644
--- a/build.gradle
+++ b/build.gradle
@@ -127,7 +127,7 @@ subprojects {
         exclude '**/BaseTestCellUtil.class'
         exclude '**/TestUnfixedBugs.class'
         exclude '**/TestOneFile.class'
-
+include '**/TestUnicodeString.class'
         // Exclude Test Suites
         exclude '**/All*Tests.class'
         exclude '**/HSSFTests.class'
@@ -381,4 +381,4 @@ project('scratchpad') {
     }
 
     japicmp.baseline = "org.apache.poi:poi:${japicmpversion}@jar"
-}
\ No newline at end of file
+}
diff --git a/src/java/org/apache/poi/hssf/record/common/ExtRst.java b/src/java/org/apache/poi/hssf/record/common/ExtRst.java
index 87e4887c52..50f41dedae 100644
--- a/src/java/org/apache/poi/hssf/record/common/ExtRst.java
+++ b/src/java/org/apache/poi/hssf/record/common/ExtRst.java
@@ -58,6 +58,7 @@ public class ExtRst implements Comparable<ExtRst>, GenericRecord {
     }
 
     protected ExtRst(ExtRst other) {
+        this();
         reserved = other.reserved;
         formattingFontIndex = other.formattingFontIndex;
         formattingOptions = other.formattingOptions;
diff --git a/src/testcases/org/apache/poi/hssf/record/common/TestUnicodeString.java b/src/testcases/org/apache/poi/hssf/record/common/TestUnicodeString.java
index 9837459393..f1016745bb 100644
--- a/src/testcases/org/apache/poi/hssf/record/common/TestUnicodeString.java
+++ b/src/testcases/org/apache/poi/hssf/record/common/TestUnicodeString.java
@@ -367,6 +367,60 @@ public final class TestUnicodeString {
         wb.close();
     }
 
+    @Test
+    public void copyExtRst() {
+        ExtRst ext = new ExtRst();
+
+        assertEquals(0, ext.getNumberOfRuns());
+        assertEquals(0, ext.getFormattingFontIndex());
+        assertEquals(0, ext.getFormattingOptions());
+        assertEquals("", ext.getPhoneticText());
+        assertEquals(0, ext.getPhRuns().length);
+        assertEquals(10, ext.getDataSize()); // Excludes 4 byte header
+
+        ExtRst copied = ext.copy();
+
+        assertEquals(0, copied.getNumberOfRuns());
+        assertEquals(0, copied.getFormattingFontIndex());
+        assertEquals(0, copied.getFormattingOptions());
+        assertEquals("", copied.getPhoneticText());
+        assertEquals(0, copied.getPhRuns().length);
+        assertEquals(10, copied.getDataSize());
+    }
+
+    @Test
+    public void copyExtRstFromData() {
+        byte[] data = new byte[]{
+                1, 0, 0x0C, 0,
+                0, 0, 0x37, 0,
+                0, 0,
+                0, 0, 0, 0,
+                0, 0 // Cruft at the end, as found from real files
+        };
+        assertEquals(16, data.length);
+
+        LittleEndianInputStream inp = new LittleEndianInputStream(
+                new ByteArrayInputStream(data)
+        );
+        ExtRst ext = new ExtRst(inp, data.length);
+        assertEquals(0x0c, ext.getDataSize()); // Excludes 4 byte header
+
+        assertEquals(0, ext.getNumberOfRuns());
+        assertEquals(0x37, ext.getFormattingOptions());
+        assertEquals(0, ext.getFormattingFontIndex());
+        assertEquals("", ext.getPhoneticText());
+        assertEquals(0, ext.getPhRuns().length);
+
+        ExtRst copied = ext.copy();
+        assertEquals(10, copied.getDataSize()); // Excludes 4 byte header
+
+        assertEquals(0, copied.getNumberOfRuns());
+        assertEquals(0x37, copied.getFormattingOptions());
+        assertEquals(0, copied.getFormattingFontIndex());
+        assertEquals("", copied.getPhoneticText());
+        assertEquals(0, copied.getPhRuns().length);
+    }
+
     private static UnicodeString makeUnicodeString(String s) {
         UnicodeString st = new UnicodeString(s);
         st.setOptionFlags((byte)0);
-- 
2.39.5