Apply hyphenation when there is only one word in a paragraph

third_party/WebKit/Source/core/layout/line/BreakingContextInlineHeaders.h

 /*
  * Copyright (C) 2000 Lars Knoll (knoll@kde.org)
  * Copyright (C) 2003, 2004, 2006, 2007, 2008, 2009, 2010, 2011 Apple Inc.
  *               All right reserved.
  * Copyright (C) 2010 Google Inc. All rights reserved.
  * Copyright (C) 2013 Adobe Systems Incorporated.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
@@ skipping 889 matching lines @@
       wordMeasurement, start + prefixLength,
       font.getCharacterRange(run, 0, prefixLength).width());
 }
 
 ALWAYS_INLINE bool BreakingContext::isBreakAtSoftHyphen() const {
   return m_lineBreak != m_resolver.position()
              ? m_lineBreak.previousInSameNode() == softHyphenCharacter
              : m_current.previousInSameNode() == softHyphenCharacter;
 }
 
+static ALWAYS_INLINE bool hasVisibleText(LineLayoutText layoutText,
+                                         unsigned offset) {
+  return !layoutText.containsOnlyWhitespace(offset,
+                                            layoutText.textLength() - offset);
+}
+
 inline bool BreakingContext::handleText(WordMeasurements& wordMeasurements,
                                         bool& hyphenated) {
   if (!m_current.offset())
     m_appliedStartWidth = false;
 
   LineLayoutText layoutText(m_current.getLineLayoutItem());
 
   // If we have left a no-wrap inline and entered an autowrap inline while
   // ignoring spaces then we need to mark the start of the autowrap inline as a
   // potential linebreak now.
@@ skipping 28 matching lines @@
 
   // This is currently only used for word-break: break-all, specifically for the
   // case where we have a break opportunity within a word, then a string of non-
   // breakable content that ends up making our word wider than the current line.
   // See: fast/css3-text/css3-word-break/word-break-all-wrap-with-floats.html
   float widthMeasurementAtLastBreakOpportunity = 0;
 
   Hyphenation* hyphenation = style.getHyphenation();
   bool disableSoftHyphen = style.getHyphens() == HyphensNone;
   float hyphenWidth = 0;
+  bool isLineEmpty = m_lineInfo.isEmpty();
 
   if (layoutText.isSVGInlineText()) {
     breakWords = false;
     breakAll = false;
     keepAll = false;
   }
 
   // Use LineBreakType::Normal for break-all. When a word does not fit,
   // rewindToMidWordBreak() finds the mid-word break point.
   LineBreakType lineBreakType =
@@ skipping 139 matching lines @@
     midWordBreak = false;
     if (!m_width.fitsOnLine()) {
       if (canBreakMidWord) {
         m_width.addUncommittedWidth(-wordMeasurement.width);
         if (rewindToMidWordBreak(layoutText, style, font, breakAll,
                                  wordMeasurement)) {
           lastWidthMeasurement = wordMeasurement.width + lastSpaceWordSpacing;
           midWordBreak = true;
         }
         m_width.addUncommittedWidth(wordMeasurement.width);
-      } else if (hyphenation) {
+      } else if (hyphenation &&
+                 (m_nextObject || isLineEmpty ||
+                  hasVisibleText(layoutText, m_current.offset()))) {
         m_width.addUncommittedWidth(-wordMeasurement.width);
         DCHECK(lastSpace == static_cast<unsigned>(wordMeasurement.startOffset));
         DCHECK(m_current.offset() ==
                static_cast<unsigned>(wordMeasurement.endOffset));
         if (hyphenate(layoutText, style, font, *hyphenation,
                       lastSpaceWordSpacing, wordMeasurement)) {
           m_width.addUncommittedWidth(wordMeasurement.width);
           hyphenated = true;
           m_atEnd = true;
           return false;
@@ skipping 68 matching lines @@
         m_lineMidpointState.startIgnoringSpaces(m_startOfIgnoredSpaces);
         m_trailingObjects.updateMidpointsForTrailingObjects(
             m_lineMidpointState, InlineIterator(),
             TrailingObjects::DoNotCollapseFirstSpace);
       }
     }
 
     prepareForNextCharacter(layoutText, prohibitBreakInside,
                             previousCharacterIsSpace);
     m_atStart = false;
+    isLineEmpty = m_lineInfo.isEmpty();
     nextCharacter(c, lastCharacter, secondToLastCharacter);
   }
 
   m_layoutTextInfo.m_lineBreakIterator.setPriorContext(lastCharacter,
                                                        secondToLastCharacter);
 
   wordMeasurements.grow(wordMeasurements.size() + 1);
   WordMeasurement& wordMeasurement = wordMeasurements.back();
   wordMeasurement.layoutText = layoutText;
 
@@ skipping 30 matching lines @@
   if (m_collapseWhiteSpace && m_currentCharacterIsSpace && lastWidthMeasurement)
     m_width.setTrailingWhitespaceWidth(lastWidthMeasurement +
                                        additionalWidthFromAncestors);
 
   m_includeEndWidth = false;
 
   if (midWordBreak) {
     m_width.commit();
     m_atEnd = true;
   } else if (!m_width.fitsOnLine()) {
-    if (hyphenation && (m_nextObject || m_lineInfo.isEmpty())) {
+    if (hyphenation && (m_nextObject || isLineEmpty)) {
       m_width.addUncommittedWidth(-wordMeasurement.width);
       DCHECK(lastSpace == static_cast<unsigned>(wordMeasurement.startOffset));
       DCHECK(m_current.offset() ==
              static_cast<unsigned>(wordMeasurement.endOffset));
       if (hyphenate(layoutText, style, font, *hyphenation, lastSpaceWordSpacing,
                     wordMeasurement)) {
         hyphenated = true;
         m_atEnd = true;
       }
       m_width.addUncommittedWidth(wordMeasurement.width);
@@ skipping 266 matching lines @@
 
   if (style.getTextIndentType() == TextIndentHanging)
     indentText = indentText == IndentText ? DoNotIndentText : IndentText;
 
   return indentText;
 }
 
 }  // namespace blink
 
 #endif  // BreakingContextInlineHeaders_h