Improve processing of block elements / images inside of a paragraph.

The getElementResult should return the same instance on each call:
otherwise the assosiated css properties will not get considered.

DEVSIX-2746

Author: ars18wrw

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

@@ -47,9 +47,12 @@ This file is part of the iText (R) project.
 import com.itextpdf.html2pdf.attach.util.WaitingInlineElementsHelper;
 import com.itextpdf.html2pdf.css.CssConstants;
 import com.itextpdf.layout.IPropertyContainer;
+import com.itextpdf.layout.element.AbstractElement;
 import com.itextpdf.layout.element.Div;
 import com.itextpdf.layout.element.IBlockElement;
+import com.itextpdf.layout.element.IElement;
 import com.itextpdf.layout.element.ILeafElement;
+import com.itextpdf.layout.element.Image;
 import com.itextpdf.layout.element.Paragraph;
 import com.itextpdf.styledxmlparser.node.IElementNode;
 
@@ -66,16 +69,17 @@ This file is part of the iText (R) project.
  *
  * <li> if the worker meets a block element without inline displaying or
  * an inline element with the {@code display: block} style, it wraps all the content which hasn't been handled yet
- * into a {@code com.itextpdf.layout.element.Paragraph} object and adds this paragraph to the {@link #elements list of elements},
- * which are going to be wrapped into a {@code com.itextpdf.layout.element.Div} object on {@link #processEnd}</li>
+ * into a {@code com.itextpdf.layout.element.Paragraph} object and adds this paragraph to the resultant {@code com.itextpdf.layout.element.Div} object
+ * </li>
  * </ul>
  */
 public class PTagWorker implements ITagWorker, IDisplayAware {
 
     /** The latest paragraph object inside tag. */
     private Paragraph lastParagraph;
-    /** List of block elements that contained in the &lt;p&gt; tag. */
-    private List<IBlockElement> elements;
+
+    /** The container which handles the elements that are present in the &lt;p&gt; tag. */
+    private Div elementsContainer;
 
     /** Helper class for waiting inline elements. */
     private WaitingInlineElementsHelper inlineHelper;
@@ -119,7 +123,11 @@ public boolean processContent(String content, ProcessorContext context) {
     public boolean processTagChild(ITagWorker childTagWorker, ProcessorContext context) {
         // TODO child might be inline, however still have display:block; it behaves like a block, however p includes it in own occupied area
         IPropertyContainer element = childTagWorker.getElementResult();
-        if (element instanceof ILeafElement) {
+        if (childTagWorker instanceof ImgTagWorker && CssConstants.BLOCK.equals(((ImgTagWorker) childTagWorker).getDisplay())) {
+            IPropertyContainer propertyContainer = childTagWorker.getElementResult();
+            processBlockElement((Image) propertyContainer);
+            return true;
+        } else if (element instanceof ILeafElement) {
             inlineHelper.add((ILeafElement) element);
             return true;
         } else if (isBlockWithDisplay(childTagWorker, element, CssConstants.INLINE_BLOCK, false)) {
@@ -153,33 +161,29 @@ public boolean processTagChild(ITagWorker childTagWorker, ProcessorContext conte
      */
     @Override
     public IPropertyContainer getElementResult() {
-        if (elements == null) {
-            return lastParagraph;
-        }
-
-        Div div = new Div();
-        for (IBlockElement element : elements) {
-            div.add(element);
-        }
-        return div;
+        return null == elementsContainer ? (IPropertyContainer) lastParagraph : (IPropertyContainer) elementsContainer;
     }
 
     @Override
     public String getDisplay() {
         return display;
     }
 
-    private void processBlockElement(IBlockElement propertyContainer) {
-        if (elements == null) {
-            elements = new ArrayList<>();
-            elements.add(lastParagraph);
+    private void processBlockElement(IElement propertyContainer) {
+        if (elementsContainer == null) {
+            elementsContainer = new Div();
+            elementsContainer.add(lastParagraph);
         }
         inlineHelper.flushHangingLeaves(lastParagraph);
 
-        elements.add(propertyContainer);
+        if (propertyContainer instanceof Image) {
+            elementsContainer.add((Image) propertyContainer);
+        } else {
+            elementsContainer.add((IBlockElement) propertyContainer);
+        }
 
         lastParagraph = new Paragraph();
-        elements.add(lastParagraph);
+        elementsContainer.add(lastParagraph);
     }
 
     private boolean isBlockWithDisplay(ITagWorker childTagWorker, IPropertyContainer element,

src/test/java/com/itextpdf/html2pdf/element/ParagraphTest.java

@@ -185,4 +185,9 @@ public void paragraphWithLabelSpanDisplayBlockTest() throws IOException, Interru
         Assert.assertNull(new CompareTool().compareByContent(destinationFolder + "paragraphWithLabelSpanDisplayBlockTest.pdf", sourceFolder + "cmp_paragraphWithLabelSpanDisplayBlockTest.pdf", destinationFolder, "diff15_"));
     }
 
+    @Test
+    public void paragraphWithImageTest01() throws IOException, InterruptedException {
+        HtmlConverter.convertToPdf(new File(sourceFolder + "paragraphWithImageTest01.html"), new File(destinationFolder + "paragraphWithImageTest01.pdf"));
+        Assert.assertNull(new CompareTool().compareByContent(destinationFolder + "paragraphWithImageTest01.pdf", sourceFolder + "cmp_paragraphWithImageTest01.pdf", destinationFolder, "diff_paragraphWithImageTest01_"));
+    }
 }

src/test/resources/com/itextpdf/html2pdf/Html2PdfTest/cmp_aBlockInPTag.pdf

@@ -0,0 +1,4 @@
+<p><img
+        style='display: block; margin-left: auto; margin-right: auto;' title='placeholder-170x70.jpg'
+        src='image.png' width='170'
+        height='70'/></p>