Bug 1134216 - Preserve line-break flags properly when applying text-transform conversions. r=smontagu

gfx/thebes/gfxTextRun.h

@@ -103,38 +103,41 @@ public:
 
     // Public textrun API for general use
 
-    bool IsClusterStart(uint32_t aPos) {
+    bool IsClusterStart(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].IsClusterStart();
     }
-    bool IsLigatureGroupStart(uint32_t aPos) {
+    bool IsLigatureGroupStart(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].IsLigatureGroupStart();
     }
-    bool CanBreakLineBefore(uint32_t aPos) {
-        NS_ASSERTION(aPos < GetLength(), "aPos out of range");
-        return mCharacterGlyphs[aPos].CanBreakBefore() ==
-            CompressedGlyph::FLAG_BREAK_TYPE_NORMAL;
+    bool CanBreakLineBefore(uint32_t aPos) const {
+        return CanBreakBefore(aPos) == CompressedGlyph::FLAG_BREAK_TYPE_NORMAL;
     }
-    bool CanHyphenateBefore(uint32_t aPos) {
-        NS_ASSERTION(aPos < GetLength(), "aPos out of range");
-        return mCharacterGlyphs[aPos].CanBreakBefore() ==
-            CompressedGlyph::FLAG_BREAK_TYPE_HYPHEN;
+    bool CanHyphenateBefore(uint32_t aPos) const {
+        return CanBreakBefore(aPos) == CompressedGlyph::FLAG_BREAK_TYPE_HYPHEN;
     }
 
-    bool CharIsSpace(uint32_t aPos) {
+    // Returns a gfxShapedText::CompressedGlyph::FLAG_BREAK_TYPE_* value
+    // as defined in gfxFont.h (may be NONE, NORMAL or HYPHEN).
+    uint8_t CanBreakBefore(uint32_t aPos) const {
+        NS_ASSERTION(aPos < GetLength(), "aPos out of range");
+        return mCharacterGlyphs[aPos].CanBreakBefore();
+    }
+
+    bool CharIsSpace(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].CharIsSpace();
     }
-    bool CharIsTab(uint32_t aPos) {
+    bool CharIsTab(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].CharIsTab();
     }
-    bool CharIsNewline(uint32_t aPos) {
+    bool CharIsNewline(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].CharIsNewline();
     }
-    bool CharIsLowSurrogate(uint32_t aPos) {
+    bool CharIsLowSurrogate(uint32_t aPos) const {
         NS_ASSERTION(aPos < GetLength(), "aPos out of range");
         return mCharacterGlyphs[aPos].CharIsLowSurrogate();
     }

layout/generic/nsTextRunTransformations.cpp

@@ -571,8 +571,9 @@ nsCaseTransformTextRunFactory::TransformString(
       aCharsToMergeArray.AppendElement(false);
       if (aTextRun) {
         aStyleArray->AppendElement(charStyle);
-        aCanBreakBeforeArray->AppendElement(inhibitBreakBefore ? false :
-                                            aTextRun->CanBreakLineBefore(i));
+        aCanBreakBeforeArray->AppendElement(
+          inhibitBreakBefore ? gfxShapedText::CompressedGlyph::FLAG_BREAK_TYPE_NONE
+                             : aTextRun->CanBreakBefore(i));
       }
 
       if (IS_IN_BMP(ch)) {
@@ -591,7 +592,8 @@ nsCaseTransformTextRunFactory::TransformString(
         aCharsToMergeArray.AppendElement(true);
         if (aTextRun) {
           aStyleArray->AppendElement(charStyle);
-          aCanBreakBeforeArray->AppendElement(false);
+          aCanBreakBeforeArray->AppendElement(
+            gfxShapedText::CompressedGlyph::FLAG_BREAK_TYPE_NONE);
         }
       }
     }