Bug 763689 patch 2: Support min-width:auto in computed style, and add special cases as necessary wherever it's read. r=dbaron

layout/base/crashtests/crashtests.list

@@ -45,7 +45,7 @@ asserts(6-12) load 265986-1.html # Bug 512405
 load 265999-1.html
 load 266222-1.html
 asserts(3-7) load 266360-1.html # bug 575011 / bug 576358
-asserts(4) load 266445-1.html # Bug 575011
+asserts(3) load 266445-1.html # Bug 575011
 load 268157-1.html
 load 269566-1.html
 load 272647-1.html

layout/base/nsLayoutUtils.cpp

@@ -2496,7 +2496,19 @@ nsLayoutUtils::IntrinsicForContainer(nsRenderingContext *aRenderingContext,
   nscoord maxw;
   bool haveFixedMaxWidth = GetAbsoluteCoord(styleMaxWidth, maxw);
   nscoord minw;
-  bool haveFixedMinWidth = GetAbsoluteCoord(styleMinWidth, minw);
+
+  // Treat "min-width: auto" as 0.
+  bool haveFixedMinWidth;
+  if (eStyleUnit_Auto == styleMinWidth.GetUnit()) {
+    // NOTE: Technically, "auto" is supposed to behave like "min-content" on
+    // flex items. However, we don't need to worry about that here, because
+    // flex items' min-sizes are intentionally ignored until the flex
+    // container explicitly considers them during space distribution.
+    minw = 0;
+    haveFixedMinWidth = true;
+  } else {
+    haveFixedMinWidth = GetAbsoluteCoord(styleMinWidth, minw);
+  }
 
   // If we have a specified width (or a specified 'min-width' greater
   // than the specified 'max-width', which works out to the same thing),
@@ -2836,9 +2848,18 @@ nsLayoutUtils::ComputeSizeWithIntrinsicDimensions(
     maxWidth = nscoord_MAX;
   }
 
-  minWidth = nsLayoutUtils::ComputeWidthValue(aRenderingContext,
+  if (stylePos->mMinWidth.GetUnit() != eStyleUnit_Auto) {
-               aFrame, aCBSize.width, boxSizingAdjust.width,
+    minWidth = nsLayoutUtils::ComputeWidthValue(aRenderingContext,
-               boxSizingToMarginEdgeWidth, stylePos->mMinWidth);
+                 aFrame, aCBSize.width, boxSizingAdjust.width,
+                 boxSizingToMarginEdgeWidth, stylePos->mMinWidth);
+  } else {
+    // Treat "min-width: auto" as 0.
+    // NOTE: Technically, "auto" is supposed to behave like "min-content" on
+    // flex items. However, we don't need to worry about that here, because
+    // flex items' min-sizes are intentionally ignored until the flex
+    // container explicitly considers them during space distribution.
+    minWidth = 0;
+  }
 
   if (!isAutoHeight) {
     height = nsLayoutUtils::ComputeHeightValue(aCBSize.height, 

layout/generic/nsFrame.cpp

@@ -3890,10 +3890,20 @@ nsFrame::ComputeSize(nsRenderingContext *aRenderingContext,
     result.width = NS_MIN(maxWidth, result.width);
   }
 
-  nscoord minWidth =
+  nscoord minWidth;
-    nsLayoutUtils::ComputeWidthValue(aRenderingContext, this,
+  if (stylePos->mMinWidth.GetUnit() != eStyleUnit_Auto) {
-      aCBSize.width, boxSizingAdjust.width, boxSizingToMarginEdgeWidth,
+    minWidth =
-      stylePos->mMinWidth);
+      nsLayoutUtils::ComputeWidthValue(aRenderingContext, this,
+        aCBSize.width, boxSizingAdjust.width, boxSizingToMarginEdgeWidth,
+        stylePos->mMinWidth);
+  } else {
+    // Treat "min-width: auto" as 0.
+    // NOTE: Technically, "auto" is supposed to behave like "min-content" on
+    // flex items. However, we don't need to worry about that here, because
+    // flex items' min-sizes are intentionally ignored until the flex
+    // container explicitly considers them during space distribution.
+    minWidth = 0;
+  }
   result.width = NS_MAX(minWidth, result.width);
 
   // Compute height

layout/generic/nsHTMLReflowState.cpp

@@ -2458,9 +2458,15 @@ nsHTMLReflowState::ComputeMinMaxValues(nscoord aContainingBlockWidth,
                                        nscoord aContainingBlockHeight,
                                        const nsHTMLReflowState* aContainingBlockRS)
 {
-  mComputedMinWidth = ComputeWidthValue(aContainingBlockWidth,
+  // Handle "min-width: auto"
-                                        mStylePosition->mBoxSizing,
+  if (eStyleUnit_Auto == mStylePosition->mMinWidth.GetUnit()) {
-                                        mStylePosition->mMinWidth);
+    // XXXdholbert For flex items, this needs to behave like -moz-min-content.
+    mComputedMinWidth = 0;
+  } else {
+    mComputedMinWidth = ComputeWidthValue(aContainingBlockWidth,
+                                          mStylePosition->mBoxSizing,
+                                          mStylePosition->mMinWidth);
+  }
 
   if (eStyleUnit_None == mStylePosition->mMaxWidth.GetUnit()) {
     // Specified value of 'none'

layout/reftests/bugs/reftest.list

@@ -20,7 +20,7 @@
 == 10036-1.html 10036-1-ref.html
 skip-if(!cocoaWidget) HTTP(..) == 10209-1.html 10209-ref.html # Bug 667079
 HTTP(..) == 10209-2.html 10209-ref.html
-asserts(4) skip-if(!cocoaWidget) HTTP(..) == 10209-3.html 10209-3-ref.html # Assertions: bug 666606, skip because of bug 667079
+asserts(2) skip-if(!cocoaWidget) HTTP(..) == 10209-3.html 10209-3-ref.html # Assertions: bug 666606, skip because of bug 667079
 == 18217-basic-1.html 18217-basic-1-ref.html
 == 18217-basic-2a.html 18217-basic-2-ref.html
 == 18217-basic-2b.html 18217-basic-2-ref.html

layout/style/nsComputedDOMStyle.cpp

@@ -3361,7 +3361,17 @@ nsIDOMCSSValue*
 nsComputedDOMStyle::DoGetMinWidth()
 {
   nsROCSSPrimitiveValue *val = GetROCSSPrimitiveValue();
-  SetValueToCoord(val, GetStylePosition()->mMinWidth, true,
+
+  nsStyleCoord minWidth = GetStylePosition()->mMinWidth;
+
+  if (eStyleUnit_Auto == minWidth.GetUnit()) {
+    // In non-flexbox contexts, "min-width: auto" means "min-width: 0".
+    // XXXdholbert For flex items, we should set |minWidth| to the
+    // -moz-min-content keyword, instead of 0.
+    minWidth.SetCoordValue(0);
+  }
+
+  SetValueToCoord(val, minWidth, true,
                   &nsComputedDOMStyle::GetCBContentWidth,
                   nsCSSProps::kWidthKTable);
   return val;

layout/style/nsRuleNode.cpp

@@ -6433,11 +6433,7 @@ nsRuleNode::ComputePositionData(void* aStartStruct,
            SETCOORD_LPOH | SETCOORD_INITIAL_NONE | SETCOORD_STORE_CALC,
            aContext, mPresContext, canStoreInRuleTree);
 
-
+  // Make 'auto' values for min-height compute to 0
-  // Handle 'auto' values for min-width / min-height
-  if (pos->mMinWidth.GetUnit() == eStyleUnit_Auto) {
-    pos->mMinWidth.SetCoordValue(0);
-  }
   if (pos->mMinHeight.GetUnit() == eStyleUnit_Auto) {
     pos->mMinHeight.SetCoordValue(0);
   }

layout/style/nsStyleStruct.cpp

@@ -1130,7 +1130,7 @@ nsStylePosition::nsStylePosition(void)
   mOffset.SetRight(autoCoord);
   mOffset.SetBottom(autoCoord);
   mWidth.SetAutoValue();
-  mMinWidth.SetCoordValue(0);
+  mMinWidth.SetAutoValue();
   mMaxWidth.SetNoneValue();
   mHeight.SetAutoValue();
   mMinHeight.SetCoordValue(0);
@@ -1252,8 +1252,7 @@ nsChangeHint nsStylePosition::MaxDifference()
 /* static */ bool
 nsStylePosition::WidthCoordDependsOnContainer(const nsStyleCoord &aCoord)
 {
-  return aCoord.GetUnit() == eStyleUnit_Auto ||
+  return aCoord.HasPercent() ||
-         aCoord.HasPercent() ||
          (aCoord.GetUnit() == eStyleUnit_Enumerated &&
           (aCoord.GetIntValue() == NS_STYLE_WIDTH_FIT_CONTENT ||
            aCoord.GetIntValue() == NS_STYLE_WIDTH_AVAILABLE));

layout/style/nsStyleStruct.h

@@ -1117,7 +1117,19 @@ struct nsStylePosition {
   nsStyleCoord  mZIndex;                // [reset] integer, auto
 
   bool WidthDependsOnContainer() const
-    { return WidthCoordDependsOnContainer(mWidth); }
+    {
+      return mWidth.GetUnit() == eStyleUnit_Auto ||
+        WidthCoordDependsOnContainer(mWidth);
+    }
+
+  // NOTE: For a flex item, "min-width:auto" is supposed to behave like
+  // "min-content", which does depend on the container, so you might think we'd
+  // need a special case for "flex item && min-width:auto" here.  However,
+  // we don't actually need that special-case code, because flex items are
+  // explicitly supposed to *ignore* their min-width (i.e. behave like it's 0)
+  // until the flex container explicitly considers it.  So -- since the flex
+  // container doesn't rely on this method, we don't need to worry about
+  // special behavior for flex items' "min-width:auto" values here.
   bool MinWidthDependsOnContainer() const
     { return WidthCoordDependsOnContainer(mMinWidth); }
   bool MaxWidthDependsOnContainer() const