Fix issues with number filtering for <input type="number">

DEVSIX-4198

Author: Snipx

src/main/java/com/itextpdf/html2pdf/attach/impl/tags/InputTagWorker.java

@@ -58,6 +58,8 @@ This file is part of the iText (R) project.
 import com.itextpdf.html2pdf.html.AttributeConstants;
 import com.itextpdf.styledxmlparser.css.util.CssUtils;
 import com.itextpdf.styledxmlparser.node.IElementNode;
+
+import java.util.regex.Pattern;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -66,6 +68,9 @@ This file is part of the iText (R) project.
  */
 public class InputTagWorker implements ITagWorker, IDisplayAware {
 
+    private static final Pattern NUMBER_INPUT_ALLOWED_VALUES =
+            Pattern.compile("^(((-?[0-9]+)(\\.[0-9]+)?)|(-?\\.[0-9]+))$");
+
     /**
      * The form element.
      */
@@ -190,8 +195,9 @@ public IPropertyContainer getElementResult() {
         return formElement;
     }
 
-    private static String preprocessInputValue(String value, String inputType) {
-        if (AttributeConstants.NUMBER.equals(inputType) && value != null && !value.matches("[0-9.]*")) {
+    static String preprocessInputValue(String value, String inputType) {
+        if (AttributeConstants.NUMBER.equals(inputType) && value != null &&
+                !NUMBER_INPUT_ALLOWED_VALUES.matcher(value).matches()) {
             value = "";
         }
         return value;

src/test/java/com/itextpdf/html2pdf/attach/impl/tags/InputTagWorkerTest.java

@@ -0,0 +1,51 @@
+/*
+    This file is part of the iText (R) project.
+    Copyright (c) 1998-2020 iText Group NV
+    Authors: iText Software.
+
+    This program is offered under a commercial and under the AGPL license.
+    For commercial licensing, contact us at https://itextpdf.com/sales.  For AGPL licensing, see below.
+
+    AGPL licensing:
+    This program is free software: you can redistribute it and/or modify
+    it under the terms of the GNU Affero General Public License as published by
+    the Free Software Foundation, either version 3 of the License, or
+    (at your option) any later version.
+
+    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 <https://www.gnu.org/licenses/>.
+ */
+package com.itextpdf.html2pdf.attach.impl.tags;
+
+import com.itextpdf.html2pdf.html.AttributeConstants;
+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 InputTagWorkerTest extends ExtendedITextTest {
+
+    @Test
+    public void testNumberInputPreprocessing() {
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue("bear", AttributeConstants.NUMBER));
+        Assert.assertEquals("4", InputTagWorker.preprocessInputValue("4", AttributeConstants.NUMBER));
+        Assert.assertEquals("04", InputTagWorker.preprocessInputValue("04", AttributeConstants.NUMBER));
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue("4.", AttributeConstants.NUMBER));
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue(".", AttributeConstants.NUMBER));
+        Assert.assertEquals(".9", InputTagWorker.preprocessInputValue(".9", AttributeConstants.NUMBER));
+        Assert.assertEquals("4.4", InputTagWorker.preprocessInputValue("4.4", AttributeConstants.NUMBER));
+        Assert.assertEquals("-4", InputTagWorker.preprocessInputValue("-4", AttributeConstants.NUMBER));
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue("", AttributeConstants.NUMBER));
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue("-", AttributeConstants.NUMBER));
+        Assert.assertEquals("-.9", InputTagWorker.preprocessInputValue("-.9", AttributeConstants.NUMBER));
+        Assert.assertEquals("", InputTagWorker.preprocessInputValue("0-.9", AttributeConstants.NUMBER));
+    }
+}