#482 #491 #483 Fix infinite loop bug with soft-hypen plus inserted hyphen overflowing line.

danfickle · danfickle · commit b8853841b44d · 2020-05-27T00:53:49.000+10:00
The core problem seems to be the under-reporting of width when we have a soft hyphen that is found to be unbreakable.
diff --git a/openhtmltopdf-core/src/main/java/com/openhtmltopdf/layout/Breaker.java b/openhtmltopdf-core/src/main/java/com/openhtmltopdf/layout/Breaker.java
@@ -173,15 +173,9 @@ public static LineBreakResult breakText(LayoutContext c,
                         context.setEnd(savedEnd);
                         continue LOOP;
                     } else {
-						if (context.getWidth() == 0) {
-							String calculatedSubstring = context.getCalculatedSubstring();
-							if (calculatedSubstring.chars().allMatch(ch -> ch == SOFT_HYPHEN)) {
-								// Consists only of soft hypen, we have to break here and skip all togheter. We do not
-                                // need to try breaking on the charater level, this will not work.
-								tryToBreakAnywhere = true;
-							}
-						}
                         // Else, retry it on a new line.
+                        // FIXME: This is very dangerous and has led to infinite
+                        // loops. Needs review.
                         context.setEnd(savedEnd);
                         break LOOP;
                     }
@@ -501,15 +495,16 @@ public static LineBreakResult doBreakText(
             context.setEnd(context.getStart() + current.left);
             context.setUnbreakable(true);
 
-            if (current.left == currentString.length()) {
+            if (current.isSoftHyphenBreak) {
+                context.setWidth(current.withHyphenGraphicsLength);
+            } else if (current.left == currentString.length()) {
                 String text = context.getCalculatedSubstring();
                 float extraSpacing = text.length() * letterSpacing;
                 context.setWidth((int) (c.getTextRenderer().getWidth(
                         c.getFontContext(), font, text) + extraSpacing));
             } else {
                 context.setWidth(current.graphicsLength);
             }
-            
             return LineBreakResult.WORD_BREAKING_UNBREAKABLE;
         }
     }
diff --git a/openhtmltopdf-examples/src/main/resources/visualtest/expected/issue-482-infinite-loop-table.pdf b/openhtmltopdf-examples/src/main/resources/visualtest/expected/issue-482-infinite-loop-table.pdf
diff --git a/openhtmltopdf-examples/src/main/resources/visualtest/html/issue-482-infinite-loop-table.html b/openhtmltopdf-examples/src/main/resources/visualtest/html/issue-482-infinite-loop-table.html
@@ -1,19 +1,19 @@
 <html>
 <head>
 <style>
-    * {
-        font-family: 'Liberation Sans', sans-serif;
-        margin: 0;
-        padding: 0;
-    }
-
+@page  {
+    size: 30px 40px;
+    margin: 0;
+    padding: 0;
+}
     .content {
+        font-family: 'Liberation Sans', sans-serif;
         word-wrap: break-word;
-        white-space:pre-wrap;
+        width: 10px;
     }
 </style>
 </head>
 <body>
-<table class="content"><tbody><tr><td width="10">&shy;</td></tr></tbody></table>
+<div class="content">&shy;</div>
 </body>
-</html>
+</html>
diff --git a/openhtmltopdf-examples/src/test/java/com/openhtmltopdf/visualregressiontests/VisualRegressionTest.java b/openhtmltopdf-examples/src/test/java/com/openhtmltopdf/visualregressiontests/VisualRegressionTest.java
@@ -1154,8 +1154,12 @@ public Reader getReader() {
         })));
     }
 
+    /**
+     * Tests another endless loop bug when the font reports a non-zero width
+     * for soft hyphen and this overflows the width of the box in break-word
+     * mode.
+     */
     @Test
-    @Ignore
     public void testIssue482InfiniteLoopTable() throws IOException {
         assertTrue(vt.runTest("issue-482-infinite-loop-table", builder -> {
             builder.useFont(() -> VisualRegressionTest.class.getClassLoader().getResourceAsStream("org/apache/pdfbox/resources/ttf/LiberationSans-Regular.ttf"),
