Changeset 89769 in webkit

Timestamp:

Jun 26, 2011 9:09:33 AM (13 years ago)

Author:

mitz@apple.com

Message:

With word-break: break-all, words do not break correctly before a surrogate pair
​https://bugs.webkit.org/show_bug.cgi?id=63401

Reviewed by Darin Adler.

Source/WebCore:

The code to check for mid-word breaks accumulates width one character at a time. It was actually
measuring the two parts of the surrogate pair individually, so they appeared to have zero width.
Fixed by checking for surrogate pairs and measuring the pair as one unit.

Test: fast/text/midword-break-before-surrogate-pair.html

• rendering/RenderBlockLineLayout.cpp:

(WebCore::RenderBlock::LineBreaker::nextLineBreak):

LayoutTests:

• fast/text/midword-break-before-surrogate-pair.html: Added.

Location:

trunk

Files:

• LayoutTests/ChangeLog (modified) (1 diff)
• LayoutTests/fast/text/midword-break-before-surrogate-pair.html (added)
• LayoutTests/platform/mac/fast/text/midword-break-before-surrogate-pair-expected.png (added)
• LayoutTests/platform/mac/fast/text/midword-break-before-surrogate-pair-expected.txt (added)
• Source/WebCore/ChangeLog (modified) (1 diff)
• Source/WebCore/rendering/RenderBlockLineLayout.cpp (modified) (2 diffs)

trunk/LayoutTests/ChangeLog

@@ +1 @@
+2011-06-26  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Darin Adler.
+
+        With word-break: break-all, words do not break correctly before a surrogate pair
+        https://bugs.webkit.org/show_bug.cgi?id=63401
+
+        * fast/text/midword-break-before-surrogate-pair.html: Added.
+
 2011-06-26  Adam Barth  <abarth@webkit.org>
 

trunk/Source/WebCore/ChangeLog

@@ +1 @@
+2011-06-26  Dan Bernstein  <mitz@apple.com>
+
+        Reviewed by Darin Adler.
+
+        With word-break: break-all, words do not break correctly before a surrogate pair
+        https://bugs.webkit.org/show_bug.cgi?id=63401
+
+        The code to check for mid-word breaks accumulates width one character at a time. It was actually
+        measuring the two parts of the surrogate pair individually, so they appeared to have zero width.
+        Fixed by checking for surrogate pairs and measuring the pair as one unit.
+
+        Test: fast/text/midword-break-before-surrogate-pair.html
+
+        * rendering/RenderBlockLineLayout.cpp:
+        (WebCore::RenderBlock::LineBreaker::nextLineBreak):
+
 2011-06-26  Dirk Schulze  <krit@webkit.org>
 

trunk/Source/WebCore/rendering/RenderBlockLineLayout.cpp

@@ -2103 +2103 @@
                 currentCharacterIsWS = currentCharacterIsSpace || (breakNBSP && c == noBreakSpace);
 
+                bool midWordBreakIsBeforeSurrogatePair = false;
                 if ((breakAll || breakWords) && !midWordBreak) {
                     wrapW += charWidth;
-                    charWidth = textWidth(t, current.m_pos, 1, f, width.committedWidth() + wrapW, isFixedPitch, collapseWhiteSpace);
+                    midWordBreakIsBeforeSurrogatePair = U16_IS_LEAD(c) && current.m_pos + 1 < t->textLength() && U16_IS_TRAIL(t->characters()[current.m_pos + 1]);
+                    charWidth = textWidth(t, current.m_pos, midWordBreakIsBeforeSurrogatePair ? 2 : 1, f, width.committedWidth() + wrapW, isFixedPitch, collapseWhiteSpace);
                     midWordBreak = width.committedWidth() + wrapW + charWidth > width.availableWidth();
                 }
@@ -2222 +2224 @@
                         lBreak.moveTo(current.m_obj, current.m_pos, current.m_nextBreakablePosition);
                         midWordBreak &= (breakWords || breakAll);
+                        if (midWordBreakIsBeforeSurrogatePair)
+                            current.fastIncrementInTextNode();
                     }