Problem with newlines in TextLayoutManager

[Jeremias Maerki]

Luca (and maybe Finn),

I think I found a problem with TextLayoutManager where NEWLINEs are not
properly handled. Consider the following block (extracted from list.fo):

          <fo:block line-height="10pt" space-before.optimum="5cm" 
            white-space-collapse="false" white-space-treatment="preserve" 
linefeed-treatment="preserve" wrap-option="no-wrap">
<![CDATA[<!-- list level 1 -->
<fo:list-block provisional-distance-between-starts="0.4cm"
               provisional-label-separation="0.15cm">

  <!-- list item -->
]]>
</fo:block>

If the FO file is parsed directly the SAX events happen to always start
with a NEWLINE and then adding exactly one line of text. In this case
the current algorithm finds the NEWLINE characters and adds the
necessary KnuthPenalty.

However, if you do an XSLT transform (as happens with my layout engine
test cases) the SAX characters() call can contain more than one line at
once. In this case the algorithm ignores the NEWLINEs (see comment). I
wonder why this was done like this. I think the whole linefeed handling
is done beforehand and all NEWLINEs still coming through this algorithm
are preserved linefeeds.

Is there some reason why my patch below would make anything worse? It
seems to fix my problem here and all my test cases still pass (at least
the ones that passed before).

Thanks for any feedback!


Index: TextLayoutManager.java
===================================================================
RCS file: 
/home/cvs/xml-fop/src/java/org/apache/fop/layoutmgr/TextLayoutManager.java,v
retrieving revision 1.29
diff -u -r1.29 TextLayoutManager.java
--- TextLayoutManager.java      25 Jan 2005 10:55:47 -0000      1.29
+++ TextLayoutManager.java      1 Feb 2005 21:33:07 -0000
@@ -788,16 +788,13 @@
                 iThisStart = iNextStart;
                 iTempStart = iNextStart;
                 MinOptMax wordIPD = new MinOptMax(0);
-                for (;
-                     iTempStart < textArray.length
-                     && textArray[iTempStart] != SPACE
-                     && textArray[iTempStart] != NBSPACE;
-                     iTempStart ++) {
-                    // ignore newline characters
-                    if (textArray[iTempStart] != NEWLINE) {
-                        wordIPD.add
-                            (new 
MinOptMax(fs.getCharWidth(textArray[iTempStart])));
-                    }
+                for (; iTempStart < textArray.length
+                        && textArray[iTempStart] != SPACE
+                        && textArray[iTempStart] != NBSPACE
+                        && textArray[iTempStart] != NEWLINE;
+                        iTempStart++) {
+                    wordIPD.add(
+                        new MinOptMax(fs.getCharWidth(textArray[iTempStart])));
                 }
                 wordIPD.add(MinOptMax.multiply(letterSpaceIPD, (iTempStart - 
iThisStart - 1)));
                 vecAreaInfo.add


Jeremias Maerki