Implement text-align-last. Bug 536557, r=dbaron

dom/interfaces/css/nsIDOMCSS2Properties.idl

@@ -620,6 +620,9 @@ interface nsIDOMCSS2Properties : nsISupports
            attribute DOMString        outlineOffset;
                                         // raises(DOMException) on setting
 
+           attribute DOMString        MozTextAlignLast;
+                                        // raises(DOMException) on setting
+
            /* Mozilla extensions */
            attribute DOMString        overflowX;
                                         // raises(DOMException) on setting

layout/base/nsStyleConsts.h

@@ -625,12 +625,13 @@ static inline mozilla::css::Side operator++(mozilla::css::Side& side, int) {
 #define NS_STYLE_TEXT_ALIGN_JUSTIFY               4
 #define NS_STYLE_TEXT_ALIGN_CHAR                  5   //align based on a certain character, for table cell
 #define NS_STYLE_TEXT_ALIGN_END                   6
-#define NS_STYLE_TEXT_ALIGN_MOZ_CENTER            7
+#define NS_STYLE_TEXT_ALIGN_AUTO                  7
-#define NS_STYLE_TEXT_ALIGN_MOZ_RIGHT             8
+#define NS_STYLE_TEXT_ALIGN_MOZ_CENTER            8
-#define NS_STYLE_TEXT_ALIGN_MOZ_LEFT              9
+#define NS_STYLE_TEXT_ALIGN_MOZ_RIGHT             9
+#define NS_STYLE_TEXT_ALIGN_MOZ_LEFT             10
 // NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT is only used in data structs; it
 // is never present in stylesheets or computed data.
-#define NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT 10
+#define NS_STYLE_TEXT_ALIGN_MOZ_CENTER_OR_INHERIT 11
 // Note: make sure that the largest NS_STYLE_TEXT_ALIGN_* value is smaller than
 // the smallest NS_STYLE_VERTICAL_ALIGN_* value below!
 
@@ -682,15 +683,15 @@ static inline mozilla::css::Side operator++(mozilla::css::Side& side, int) {
 // Note: these values pickup after the text-align values because there
 // are a few html cases where an object can have both types of
 // alignment applied with a single attribute
-#define NS_STYLE_VERTICAL_ALIGN_BASELINE             11
+#define NS_STYLE_VERTICAL_ALIGN_BASELINE             12
-#define NS_STYLE_VERTICAL_ALIGN_SUB                  12
+#define NS_STYLE_VERTICAL_ALIGN_SUB                  13
-#define NS_STYLE_VERTICAL_ALIGN_SUPER                13
+#define NS_STYLE_VERTICAL_ALIGN_SUPER                14
-#define NS_STYLE_VERTICAL_ALIGN_TOP                  14
+#define NS_STYLE_VERTICAL_ALIGN_TOP                  15
-#define NS_STYLE_VERTICAL_ALIGN_TEXT_TOP             15
+#define NS_STYLE_VERTICAL_ALIGN_TEXT_TOP             16
-#define NS_STYLE_VERTICAL_ALIGN_MIDDLE               16
+#define NS_STYLE_VERTICAL_ALIGN_MIDDLE               17
-#define NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM          17
+#define NS_STYLE_VERTICAL_ALIGN_TEXT_BOTTOM          18
-#define NS_STYLE_VERTICAL_ALIGN_BOTTOM               18
+#define NS_STYLE_VERTICAL_ALIGN_BOTTOM               19
-#define NS_STYLE_VERTICAL_ALIGN_MIDDLE_WITH_BASELINE 19
+#define NS_STYLE_VERTICAL_ALIGN_MIDDLE_WITH_BASELINE 20
 
 // See nsStyleVisibility
 #define NS_STYLE_VISIBILITY_HIDDEN              0

layout/generic/nsBlockFrame.cpp

@@ -4107,16 +4107,15 @@ nsBlockFrame::SplitLine(nsBlockReflowState& aState,
 }
 
 bool
-nsBlockFrame::ShouldJustifyLine(nsBlockReflowState& aState,
+nsBlockFrame::IsLastLine(nsBlockReflowState& aState,
                          line_iterator aLine)
 {
   while (++aLine != end_lines()) {
     // There is another line
     if (0 != aLine->GetChildCount()) {
-      // If the next line is a block line then we must not justify
+      // If the next line is a block line then this line is the last in a
-      // this line because it means that this line is the last in a
       // group of inline lines.
-      return !aLine->IsBlock();
+      return aLine->IsBlock();
     }
     // The next line is empty, try the next one
   }
@@ -4131,13 +4130,13 @@ nsBlockFrame::ShouldJustifyLine(nsBlockReflowState& aState,
          ++line)
     {
       if (0 != line->GetChildCount())
-        return !line->IsBlock();
+        return line->IsBlock();
     }
     nextInFlow = (nsBlockFrame*) nextInFlow->GetNextInFlow();
   }
 
   // This is the last line - so don't allow justification
-  return false;
+  return true;
 }
 
 bool
@@ -4222,10 +4221,19 @@ nsBlockFrame::PlaceLine(nsBlockReflowState& aState,
   // inline frames "shrink-wrap" around their children (therefore
   // there is no extra horizontal space).
   const nsStyleText* styleText = GetStyleText();
-  bool allowJustify = NS_STYLE_TEXT_ALIGN_JUSTIFY == styleText->mTextAlign &&
+
-                        !aLineLayout.GetLineEndsInBR() &&
+  /**
-                        ShouldJustifyLine(aState, aLine);
+   * text-align-last defaults to the same value as text-align when
-  aLineLayout.HorizontalAlignFrames(aLine->mBounds, allowJustify);
+   * text-align-last is set to auto (unless when text-align is set to justify),
+   * so in that case we don't need to set isLastLine.
+   *
+   * In other words, isLastLine really means isLastLineAndWeCare.
+   */
+  bool isLastLine = ((NS_STYLE_TEXT_ALIGN_AUTO != styleText->mTextAlignLast ||
+                            NS_STYLE_TEXT_ALIGN_JUSTIFY == styleText->mTextAlign) &&
+                       (aLineLayout.GetLineEndsInBR() ||
+                        IsLastLine(aState, aLine)));
+  aLineLayout.HorizontalAlignFrames(aLine->mBounds, isLastLine);
   // XXX: not only bidi: right alignment can be broken after
   // RelativePositionFrames!!!
   // XXXldb Is something here considering relatively positioned frames at

layout/generic/nsBlockFrame.h

@@ -530,7 +530,7 @@ protected:
                          const nsLineList* aLineList = nsnull);
 
   // XXX where to go
-  bool ShouldJustifyLine(nsBlockReflowState& aState,
+  bool IsLastLine(nsBlockReflowState& aState,
                   line_iterator aLine);
 
   void DeleteLine(nsBlockReflowState& aState,

layout/generic/nsLineLayout.cpp

@@ -113,7 +113,6 @@ nsLineLayout::nsLineLayout(nsPresContext* aPresContext,
 
   // Stash away some style data that we need
   mStyleText = aOuterReflowState->frame->GetStyleText();
-  mTextAlign = mStyleText->mTextAlign;
   mLineNumber = 0;
   mFlags = 0; // default all flags to false except those that follow here...
   mTotalPlacedFrames = 0;
@@ -2493,8 +2492,12 @@ nsLineLayout::ApplyFrameJustification(PerSpanData* aPSD, FrameJustificationState
 
 void
 nsLineLayout::HorizontalAlignFrames(nsRect& aLineBounds,
-                                    bool aAllowJustify)
+                                    bool aIsLastLine)
 {
+  /**
+   * NOTE: aIsLastLine ain't necessarily so: it is correctly set by caller
+   * only in cases where the last line needs special handling.
+   */
   PerSpanData* psd = mRootSpan;
   NS_WARN_IF_FALSE(psd->mRightEdge != NS_UNCONSTRAINEDSIZE,
                    "have unconstrained width; this should only result from "
@@ -2510,11 +2513,27 @@ nsLineLayout::HorizontalAlignFrames(nsRect& aLineBounds,
   nscoord dx = 0;
 
   if (remainingWidth > 0) {
-    switch (mTextAlign) {
+    PRUint8 textAlign = mStyleText->mTextAlign;
+
+    /* 
+     * 'text-align-last: auto' is equivalent to the value of the 'text-align'
+     * property except when 'text-align' is set to 'justify', in which case it
+     * is 'justify' when 'text-justify' is 'distribute' and 'start' otherwise.
+     *
+     * XXX: the code below will have to change when we implement text-justify
+     */
+    if (aIsLastLine) {
+      if (mStyleText->mTextAlignLast == NS_STYLE_TEXT_ALIGN_AUTO) {
+        if (textAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY) {
+          textAlign = NS_STYLE_TEXT_ALIGN_DEFAULT;
+        }
+      } else {
+        textAlign = mStyleText->mTextAlignLast;
+      }
+    }
+
+    switch (textAlign) {
       case NS_STYLE_TEXT_ALIGN_JUSTIFY:
-        // If this is not the last line then go ahead and justify the
-        // frames in the line.
-        if (aAllowJustify) {
         PRInt32 numSpaces;
         PRInt32 numLetters;
             
@@ -2530,9 +2549,8 @@ nsLineLayout::HorizontalAlignFrames(nsRect& aLineBounds,
           remainingWidth = availWidth - aLineBounds.width;
           break;
         }
-        }
+        // Fall through to the default case if we could not justify to fill
-        // Fall through to the default case if we were told not to
+        // the space.
-        // justify anything or could not justify to fill the space.
 
       case NS_STYLE_TEXT_ALIGN_DEFAULT:
         if (NS_STYLE_DIRECTION_LTR == psd->mDirection) {

layout/generic/nsLineLayout.h

@@ -134,7 +134,7 @@ public:
 
   bool TrimTrailingWhiteSpace();
 
-  void HorizontalAlignFrames(nsRect& aLineBounds, bool aAllowJustify);
+  void HorizontalAlignFrames(nsRect& aLineBounds, bool aIsLastLine);
 
   /**
    * Handle all the relative positioning in the line, compute the
@@ -568,8 +568,6 @@ protected:
 
   PRUint32 mFlags;
 
-  PRUint8 mTextAlign;
-
   nsresult NewPerFrameData(PerFrameData** aResult);
 
   nsresult NewPerSpanData(PerSpanData** aResult);

layout/generic/nsTextFrameThebes.cpp

@@ -1765,7 +1765,8 @@ BuildTextRunsScanner::BuildTextRunForFrames(void* aTextBuffer)
   PRUint32 nextBreakIndex = 0;
   nsTextFrame* nextBreakBeforeFrame = GetNextBreakBeforeFrame(&nextBreakIndex);
   bool enabledJustification = mLineContainer &&
-    mLineContainer->GetStyleText()->mTextAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY;
+    (mLineContainer->GetStyleText()->mTextAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY ||
+     mLineContainer->GetStyleText()->mTextAlignLast == NS_STYLE_TEXT_ALIGN_JUSTIFY);
 
   PRUint32 i;
   const nsStyleText* textStyle = nsnull;
@@ -7674,7 +7675,8 @@ nsTextFrame::ReflowText(nsLineLayout& aLineLayout, nscoord aAvailableWidth,
 
   // Compute space and letter counts for justification, if required
   if (!textStyle->WhiteSpaceIsSignificant() &&
-      lineContainer->GetStyleText()->mTextAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY) {
+      (lineContainer->GetStyleText()->mTextAlign == NS_STYLE_TEXT_ALIGN_JUSTIFY ||
+       lineContainer->GetStyleText()->mTextAlignLast == NS_STYLE_TEXT_ALIGN_JUSTIFY)) {
     AddStateBits(TEXT_JUSTIFICATION_ENABLED);    // This will include a space for trailing whitespace, if any is present.
     // This is corrected for in nsLineLayout::TrimWhiteSpaceIn.
     PRInt32 numJustifiableCharacters =

layout/style/nsCSSPropList.h

@@ -2208,6 +2208,15 @@ CSS_PROP_TEXT(
     kTextAlignKTable,
     CSS_PROP_NO_OFFSET,
     eStyleAnimType_None)
+CSS_PROP_TEXT(
+    -moz-text-align-last,
+    text_align_last,
+    CSS_PROP_DOMPROP_PREFIXED(TextAlignLast),
+    CSS_PROPERTY_PARSE_VALUE,
+    VARIANT_HK,
+    kTextAlignLastKTable,
+    offsetof(nsStyleText, mTextAlignLast),
+    eStyleAnimType_None)
 CSS_PROP_SHORTHAND(
     text-decoration,
     text_decoration,

layout/style/nsCSSProps.cpp

@@ -1200,6 +1200,17 @@ const PRInt32 nsCSSProps::kTextAlignKTable[] = {
   eCSSKeyword_UNKNOWN,-1
 };
 
+const PRInt32 nsCSSProps::kTextAlignLastKTable[] = {
+  eCSSKeyword_auto, NS_STYLE_TEXT_ALIGN_AUTO,
+  eCSSKeyword_left, NS_STYLE_TEXT_ALIGN_LEFT,
+  eCSSKeyword_right, NS_STYLE_TEXT_ALIGN_RIGHT,
+  eCSSKeyword_center, NS_STYLE_TEXT_ALIGN_CENTER,
+  eCSSKeyword_justify, NS_STYLE_TEXT_ALIGN_JUSTIFY,
+  eCSSKeyword_start, NS_STYLE_TEXT_ALIGN_DEFAULT,
+  eCSSKeyword_end, NS_STYLE_TEXT_ALIGN_END,
+  eCSSKeyword_UNKNOWN,-1
+};
+
 const PRInt32 nsCSSProps::kTextBlinkKTable[] = {
   eCSSKeyword_none, NS_STYLE_TEXT_BLINK_NONE,
   eCSSKeyword_blink, NS_STYLE_TEXT_BLINK_BLINK,

layout/style/nsCSSProps.h

@@ -408,6 +408,7 @@ public:
   static const PRInt32 kStackSizingKTable[];
   static const PRInt32 kTableLayoutKTable[];
   static const PRInt32 kTextAlignKTable[];
+  static const PRInt32 kTextAlignLastKTable[];
   static const PRInt32 kTextBlinkKTable[];
   static const PRInt32 kTextDecorationLineKTable[];
   static const PRInt32 kTextDecorationStyleKTable[];

layout/style/nsComputedDOMStyle.cpp

@@ -2401,6 +2401,16 @@ nsComputedDOMStyle::DoGetTextAlign()
   return val;
 }
 
+nsIDOMCSSValue*
+nsComputedDOMStyle::DoGetTextAlignLast()
+{
+  nsROCSSPrimitiveValue* val = GetROCSSPrimitiveValue();
+  val->SetIdent(
+    nsCSSProps::ValueToKeywordEnum(GetStyleText()->mTextAlignLast,
+                                   nsCSSProps::kTextAlignLastKTable));
+  return val;
+}
+
 nsIDOMCSSValue*
 nsComputedDOMStyle::DoGetMozTextBlink()
 {
@@ -4575,6 +4585,7 @@ nsComputedDOMStyle::GetQueryablePropertyMap(PRUint32* aLength)
     //// COMPUTED_STYLE_MAP_ENTRY(size,                     Size),
     COMPUTED_STYLE_MAP_ENTRY(table_layout,                  TableLayout),
     COMPUTED_STYLE_MAP_ENTRY(text_align,                    TextAlign),
+    COMPUTED_STYLE_MAP_ENTRY(text_align_last,               TextAlignLast),
     COMPUTED_STYLE_MAP_ENTRY(text_decoration,               TextDecoration),
     COMPUTED_STYLE_MAP_ENTRY_LAYOUT(text_indent,            TextIndent),
     COMPUTED_STYLE_MAP_ENTRY(text_overflow,                 TextOverflow),

layout/style/nsComputedDOMStyle.h

@@ -313,6 +313,7 @@ private:
   /* Text Properties */
   nsIDOMCSSValue* DoGetLineHeight();
   nsIDOMCSSValue* DoGetTextAlign();
+  nsIDOMCSSValue* DoGetTextAlignLast();
   nsIDOMCSSValue* DoGetMozTextBlink();
   nsIDOMCSSValue* DoGetTextDecoration();
   nsIDOMCSSValue* DoGetMozTextDecorationColor();

layout/style/nsRuleNode.cpp

@@ -3365,6 +3365,11 @@ nsRuleNode::ComputeTextData(void* aStartStruct,
                 NS_STYLE_TEXT_ALIGN_DEFAULT,
                 0, 0, 0, 0);
 
+  // text-align-last: enum, inherit, initial
+  SetDiscrete(*aRuleData->ValueForTextAlignLast(), text->mTextAlignLast,
+              canStoreInRuleTree, SETDSC_ENUMERATED, parentText->mTextAlignLast,
+              NS_STYLE_TEXT_ALIGN_AUTO, 0, 0, 0, 0);
+
   // text-indent: length, percent, calc, inherit, initial
   SetCoord(*aRuleData->ValueForTextIndent(), text->mTextIndent, parentText->mTextIndent,
            SETCOORD_LPH | SETCOORD_INITIAL_ZERO | SETCOORD_STORE_CALC,

layout/style/nsStyleStruct.cpp

@@ -2814,6 +2814,7 @@ nsStyleText::nsStyleText(void)
 { 
   MOZ_COUNT_CTOR(nsStyleText);
   mTextAlign = NS_STYLE_TEXT_ALIGN_DEFAULT;
+  mTextAlignLast = NS_STYLE_TEXT_ALIGN_AUTO;
   mTextTransform = NS_STYLE_TEXT_TRANSFORM_NONE;
   mWhiteSpace = NS_STYLE_WHITESPACE_NORMAL;
   mWordWrap = NS_STYLE_WORDWRAP_NORMAL;
@@ -2831,6 +2832,7 @@ nsStyleText::nsStyleText(void)
 
 nsStyleText::nsStyleText(const nsStyleText& aSource)
   : mTextAlign(aSource.mTextAlign),
+    mTextAlignLast(aSource.mTextAlignLast),
     mTextTransform(aSource.mTextTransform),
     mWhiteSpace(aSource.mWhiteSpace),
     mWordWrap(aSource.mWordWrap),
@@ -2859,6 +2861,7 @@ nsChangeHint nsStyleText::CalcDifference(const nsStyleText& aOther) const
   }
 
   if ((mTextAlign != aOther.mTextAlign) ||
+      (mTextAlignLast != aOther.mTextAlignLast) ||
       (mTextTransform != aOther.mTextTransform) ||
       (mWhiteSpace != aOther.mWhiteSpace) ||
       (mWordWrap != aOther.mWordWrap) ||

layout/style/nsStyleStruct.h

@@ -1277,6 +1277,7 @@ struct nsStyleText {
   static bool ForceCompare() { return false; }
 
   PRUint8 mTextAlign;                   // [inherited] see nsStyleConsts.h
+  PRUint8 mTextAlignLast;               // [inherited] see nsStyleConsts.h
   PRUint8 mTextTransform;               // [inherited] see nsStyleConsts.h
   PRUint8 mWhiteSpace;                  // [inherited] see nsStyleConsts.h
   PRUint8 mWordWrap;                    // [inherited] see nsStyleConsts.h

layout/style/test/property_database.js

@@ -2646,6 +2646,14 @@ var gCSSProperties = {
 		other_values: [ "center", "justify", "end" ],
 		invalid_values: []
 	},
+	"-moz-text-align-last": {
+		domProp: "MozTextAlignLast",
+		inherited: true,
+		type: CSS_TYPE_LONGHAND,
+		initial_values: [ "auto" ],
+		other_values: [ "center", "justify", "start", "end", "left", "right" ],
+		invalid_values: []
+	},
 	"-moz-text-blink": {
 		domProp: "MozTextBlink",
 		inherited: false,