Explicitly fallback to zero when NaN is attempted to be written

This was already how Java behaved in non-high-precision cases. However NaN processing would produce corrupted PDF in Java for highPrecision case and also caused exceptions in .NET.

DEVSIX-2835

Author: yulian-gaponenko

io/src/main/java/com/itextpdf/io/LogMessageConstant.java

@@ -52,6 +52,7 @@ public final class LogMessageConstant {
     public static final String ALREADY_FLUSHED_INDIRECT_OBJECT_MADE_FREE = "An attempt is made to free already flushed indirect object reference. Indirect reference wasn't freed.";
     public static final String ALREADY_TAGGED_HINT_MARKED_ARTIFACT = "A layout tagging hint for which an actual tag was already created in tags structure is marked as artifact. Existing tag will be left in the tags tree.";
     public static final String ASSOCIATED_FILE_SPEC_SHALL_INCLUDE_AFRELATIONSHIP = "For associated files their associated file specification dictionaries shall include the AFRelationship key.";
+    public static final String ATTEMPT_PROCESS_NAN = "Attempt to process NaN in PdfNumber or when writing to PDF. Zero value will be used as a fallback.";
     public static final String ATTEMPT_TO_CREATE_A_TAG_FOR_FINISHED_HINT = "Attempt to create a tag for a hint which is already marked as finished, tag will not be created.";
     public static final String ATTEMPT_TO_MOVE_TO_FLUSHED_PARENT = "An attempt is made to move the tag tree pointer to the tag parent which has been already flushed. Tag tree pointer is moved to the root tag instead.";
     public static final String CALCULATE_HASHCODE_FOR_MODIFIED_PDFNUMBER = "Calculate hashcode for modified PdfNumber.";
@@ -126,10 +127,10 @@ public final class LogMessageConstant {
     public static final String MAPPING_IN_STRUCT_ROOT_OVERWRITTEN = "Existing mapping for {0} in structure tree root role map was {1} and it was overwritten with {2}.";
     public static final String METHOD_IS_NOT_IMPLEMENTED_BY_DEFAULT_OTHER_METHOD_WILL_BE_USED = "Method {0} is not implemented by default: please, override and implement it. {1} will be used instead.";
     public static final String NAME_ALREADY_EXISTS_IN_THE_NAME_TREE = "Name \"{0}\" already exists in the name tree; old value will be replaced by the new one.";
-    public static final String N_ENTRY_IS_REQUIRED_FOR_APPEARANCE_DICTIONARY = "\\N entry is required to be present in an appearance dictionary.";
     public static final String NOT_TAGGED_PAGES_IN_TAGGED_DOCUMENT = "Not tagged pages are copied to the tagged document. Destination document now may contain not tagged content.";
     public static final String NO_FIELDS_IN_ACROFORM = "Required AcroForm entry /Fields does not exist in the document. Empty array /Fields will be created.";
     public static final String NUM_TREE_SHALL_NOT_END_WITH_KEY = "Number tree ends with a key which is invalid according to the PDF specification.";
+    public static final String N_ENTRY_IS_REQUIRED_FOR_APPEARANCE_DICTIONARY = "\\N entry is required to be present in an appearance dictionary.";
     public static final String OCCUPIED_AREA_HAS_NOT_BEEN_INITIALIZED = "Occupied area has not been initialized. {0}";
     public static final String OCSP_STATUS_IS_REVOKED = "OCSP status is revoked.";
     public static final String OCSP_STATUS_IS_UNKNOWN = "OCSP status is unknown.";

io/src/main/java/com/itextpdf/io/source/ByteUtils.java

@@ -43,9 +43,12 @@ This file is part of the iText (R) project.
  */
 package com.itextpdf.io.source;
 
+import com.itextpdf.io.LogMessageConstant;
 import com.itextpdf.io.util.DecimalFormatUtil;
 
 import java.nio.charset.StandardCharsets;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
 
 public final class ByteUtils {
 
@@ -125,6 +128,11 @@ static byte[] getIsoBytes(double d, ByteBuffer buffer) {
     }
 
     static byte[] getIsoBytes(double d, ByteBuffer buffer, boolean highPrecision) {
+        if (Double.isNaN(d)) {
+            Logger logger = LoggerFactory.getLogger(ByteUtils.class);
+            logger.error(LogMessageConstant.ATTEMPT_PROCESS_NAN);
+            d = 0;
+        }
         if (highPrecision) {
             if (Math.abs(d) < 0.000001) {
                 if (buffer != null) {

io/src/test/java/com/itextpdf/io/source/WriteNumbersTest.java

@@ -42,7 +42,11 @@ This file is part of the iText (R) project.
  */
 package com.itextpdf.io.source;
 
+import com.itextpdf.io.LogMessageConstant;
 import com.itextpdf.io.util.DecimalFormatUtil;
+import com.itextpdf.test.ExtendedITextTest;
+import com.itextpdf.test.annotations.LogMessage;
+import com.itextpdf.test.annotations.LogMessages;
 import com.itextpdf.test.annotations.type.UnitTest;
 
 import java.nio.charset.StandardCharsets;
@@ -53,14 +57,14 @@ This file is part of the iText (R) project.
 import org.junit.experimental.categories.Category;
 
 @Category(UnitTest.class)
-public class WriteNumbersTest {
+public class WriteNumbersTest extends ExtendedITextTest {
 
     public static double round(double value, int places) {
         return Math.round(value * Math.pow(10, places)) / Math.pow(10, places);
     }
 
     @Test
-    public void WriteNumber1Test() {
+    public void writeNumber1Test() {
         Random rnd = new Random();
         for (int i = 0; i < 100000; i++) {
             double d = (double)rnd.nextInt(2120000000)/100000;
@@ -77,7 +81,7 @@ public void WriteNumber1Test() {
     }
 
     @Test
-    public void WriteNumber2Test() {
+    public void writeNumber2Test() {
         Random rnd = new Random();
         for (int i = 0; i < 100000; i++) {
             double d = (double)rnd.nextInt(1000000)/1000000;
@@ -91,7 +95,7 @@ public void WriteNumber2Test() {
     }
 
     @Test
-    public void WriteNumber3Test() {
+    public void writeNumber3Test() {
         Random rnd = new Random();
         for (int i = 0; i < 100000; i++) {
             double d = rnd.nextDouble(); if (d < 32700) d*= 100000;
@@ -102,4 +106,28 @@ public void WriteNumber3Test() {
             Assert.assertArrayEquals(message, expecteds, actuals);
         }
     }
+
+    @Test
+    @LogMessages(messages = @LogMessage(messageTemplate = LogMessageConstant.ATTEMPT_PROCESS_NAN))
+    public void writeNanTest() {
+        double d = Double.NaN;
+
+        byte[] actuals = ByteUtils.getIsoBytes(d);
+        byte[] expecteds = DecimalFormatUtil.formatNumber(0, "0.##").getBytes(StandardCharsets.ISO_8859_1);
+
+        String message = "Expects: " + new String(expecteds) + ", actual: " + new String(actuals) + " \\\\ "+ d;
+        Assert.assertArrayEquals(message, expecteds, actuals);
+    }
+
+    @Test
+    @LogMessages(messages = @LogMessage(messageTemplate = LogMessageConstant.ATTEMPT_PROCESS_NAN))
+    public void writeNanHighPrecisionTest() {
+        double d = Double.NaN;
+
+        byte[] actuals = ByteUtils.getIsoBytes(d, null, true);
+        byte[] expecteds = DecimalFormatUtil.formatNumber(0, "0.##").getBytes(StandardCharsets.ISO_8859_1);
+
+        String message = "Expects: " + new String(expecteds) + ", actual: " + new String(actuals) + " \\\\ "+ d;
+        Assert.assertArrayEquals(message, expecteds, actuals);
+    }
 }

kernel/src/test/java/com/itextpdf/kernel/pdf/PdfArrayTest.java

@@ -43,13 +43,14 @@ This file is part of the iText (R) project.
 package com.itextpdf.kernel.pdf;
 
 import com.itextpdf.io.source.ByteArrayOutputStream;
+import com.itextpdf.test.ExtendedITextTest;
 import com.itextpdf.test.annotations.type.UnitTest;
 import org.junit.Assert;
 import org.junit.Test;
 import org.junit.experimental.categories.Category;
 
 @Category(UnitTest.class)
-public class PdfArrayTest {
+public class PdfArrayTest extends ExtendedITextTest {
 
     @Test
     public void testValuesIndirectContains() {

kernel/src/test/java/com/itextpdf/kernel/pdf/PdfNumberTest.java

@@ -0,0 +1,64 @@
+/*
+    This file is part of the iText (R) project.
+    Copyright (c) 1998-2019 iText Group NV
+    Authors: iText Software.
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License version 3
+    as published by the Free Software Foundation with the addition of the
+    following permission added to Section 15 as permitted in Section 7(a):
+    FOR ANY PART OF THE COVERED WORK IN WHICH THE COPYRIGHT IS OWNED BY
+    ITEXT GROUP. ITEXT GROUP DISCLAIMS THE WARRANTY OF NON INFRINGEMENT
+    OF THIRD PARTY RIGHTS
+
+    This program is distributed in the hope that it will be useful, but
+    WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+    or FITNESS FOR A PARTICULAR PURPOSE.
+    See the GNU Affero General Public License for more details.
+    You should have received a copy of the GNU Affero General Public License
+    along with this program; if not, see http://www.gnu.org/licenses or write to
+    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+    Boston, MA, 02110-1301 USA, or download the license from the following URL:
+    http://itextpdf.com/terms-of-use/
+
+    The interactive user interfaces in modified source and object code versions
+    of this program must display Appropriate Legal Notices, as required under
+    Section 5 of the GNU Affero General Public License.
+
+    In accordance with Section 7(b) of the GNU Affero General Public License,
+    a covered work must retain the producer line in every PDF that is created
+    or manipulated using iText.
+
+    You can be released from the requirements of the license by purchasing
+    a commercial license. Buying such a license is mandatory as soon as you
+    develop commercial activities involving the iText software without
+    disclosing the source code of your own applications.
+    These activities include: offering paid services to customers as an ASP,
+    serving PDFs on the fly in a web application, shipping iText with a closed
+    source product.
+
+    For more information, please contact iText Software Corp. at this
+    address: [email protected]
+ */
+package com.itextpdf.kernel.pdf;
+
+import com.itextpdf.io.LogMessageConstant;
+import com.itextpdf.test.ExtendedITextTest;
+import com.itextpdf.test.annotations.LogMessage;
+import com.itextpdf.test.annotations.LogMessages;
+import com.itextpdf.test.annotations.type.UnitTest;
+import org.junit.Assert;
+import org.junit.Test;
+import org.junit.experimental.categories.Category;
+
+@Category(UnitTest.class)
+public class PdfNumberTest extends ExtendedITextTest {
+
+    @Test
+    @LogMessages(messages = @LogMessage(messageTemplate = LogMessageConstant.ATTEMPT_PROCESS_NAN))
+    public void testNaN() {
+        PdfNumber number = new PdfNumber(Double.NaN);
+        byte[] expected = {48}; // code for "0"
+        Assert.assertArrayEquals(expected, number.getInternalContent());
+    }
+}