Bug 1290023 - Allow enum class values to be passed to other nsCSSProps methods and stored in nsCSSValue/StyleAnimationValue. r=xidorn

MozReview-Commit-ID: 62usVamI3GA

layout/style/StyleAnimationValue.cpp

@@ -3575,7 +3575,7 @@ StyleClipBasicShapeToCSSArray(const nsStyleClipPath& aClipPath,
       MOZ_ASSERT_UNREACHABLE("Unknown shape type");
       return false;
   }
-  aResult->Item(1).SetIntValue(uint8_t(aClipPath.GetSizingBox()),
+  aResult->Item(1).SetIntValue(aClipPath.GetSizingBox(),
                                eCSSUnit_Enumerated);
   return true;
 }
@@ -3966,7 +3966,7 @@ StyleAnimationValue::ExtractComputedValue(nsCSSProperty aProperty,
             result->SetURLValue(url);
             aComputedValue.SetAndAdoptCSSValueValue(result.release(), eUnit_URL);
           } else if (type == StyleClipPathType::Box) {
-            aComputedValue.SetIntValue(uint8_t(clipPath.GetSizingBox()),
+            aComputedValue.SetIntValue(clipPath.GetSizingBox(),
                                        eUnit_Enumerated);
           } else if (type == StyleClipPathType::Shape) {
             RefPtr<nsCSSValue::Array> result = nsCSSValue::Array::Create(2);

layout/style/StyleAnimationValue.h

@@ -430,6 +430,14 @@ public:
   void SetAutoValue();
   void SetNoneValue();
   void SetIntValue(int32_t aInt, Unit aUnit);
+  template<typename T,
+           typename = typename std::enable_if<std::is_enum<T>::value>::type>
+  void SetIntValue(T aInt, Unit aUnit)
+  {
+    static_assert(mozilla::IsEnumFittingWithin<T, int32_t>::value,
+                  "aValue must be an enum that fits within mValue.mInt");
+    SetIntValue(static_cast<int32_t>(aInt), aUnit);
+  }
   void SetCoordValue(nscoord aCoord);
   void SetPercentValue(float aPercent);
   void SetFloatValue(float aFloat);

layout/style/nsCSSProps.h

@@ -449,11 +449,29 @@ public:
                           int32_t& aValue);
   // Return the first keyword in |aTable| that has the corresponding value |aValue|.
   // Return |eCSSKeyword_UNKNOWN| if not found.
-  static nsCSSKeyword ValueToKeywordEnum(int32_t aValue, 
+  static nsCSSKeyword ValueToKeywordEnum(int32_t aValue,
                                          const KTableEntry aTable[]);
+  template<typename T,
+           typename = typename std::enable_if<std::is_enum<T>::value>::type>
+  static nsCSSKeyword ValueToKeywordEnum(T aValue,
+                                         const KTableEntry aTable[])
+  {
+    static_assert(mozilla::IsEnumFittingWithin<T, int16_t>::value,
+                  "aValue must be an enum that fits within KTableEntry::mValue");
+    return ValueToKeywordEnum(static_cast<int16_t>(aValue), aTable);
+  }
   // Ditto but as a string, return "" when not found.
   static const nsAFlatCString& ValueToKeyword(int32_t aValue,
                                               const KTableEntry aTable[]);
+  template<typename T,
+           typename = typename std::enable_if<std::is_enum<T>::value>::type>
+  static const nsAFlatCString& ValueToKeyword(T aValue,
+                                              const KTableEntry aTable[])
+  {
+    static_assert(mozilla::IsEnumFittingWithin<T, int16_t>::value,
+                  "aValue must be an enum that fits within KTableEntry::mValue");
+    return ValueToKeyword(static_cast<int16_t>(aValue), aTable);
+  }
 
   static const nsStyleStructID kSIDTable[eCSSProperty_COUNT_no_shorthands];
   static const KTableEntry* const kKeywordTableTable[eCSSProperty_COUNT_no_shorthands];

layout/style/nsCSSValue.h

@@ -8,6 +8,8 @@
 #ifndef nsCSSValue_h___
 #define nsCSSValue_h___
 
+#include <type_traits>
+
 #include "mozilla/Attributes.h"
 #include "mozilla/MemoryReporting.h"
 #include "mozilla/SheetType.h"
@@ -18,6 +20,7 @@
 #include "nsCOMPtr.h"
 #include "nsCSSKeywords.h"
 #include "nsCSSProperty.h"
+#include "nsCSSProps.h"
 #include "nsColor.h"
 #include "nsCoord.h"
 #include "nsProxyRelease.h"
@@ -725,6 +728,14 @@ private:
 
 public:
   void SetIntValue(int32_t aValue, nsCSSUnit aUnit);
+  template<typename T,
+           typename = typename std::enable_if<std::is_enum<T>::value>::type>
+  void SetIntValue(T aValue, nsCSSUnit aUnit)
+  {
+    static_assert(mozilla::IsEnumFittingWithin<T, int32_t>::value,
+                  "aValue must be an enum that fits within mValue.mInt");
+    SetIntValue(static_cast<int32_t>(aValue), aUnit);
+  }
   void SetPercentValue(float aValue);
   void SetFloatValue(float aValue, nsCSSUnit aUnit);
   void SetStringValue(const nsString& aValue, nsCSSUnit aUnit);

layout/style/nsComputedDOMStyle.cpp

@@ -4175,7 +4175,7 @@ nsComputedDOMStyle::DoGetBoxSizing()
 {
   RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;
   val->SetIdent(
-    nsCSSProps::ValueToKeywordEnum(uint8_t(StylePosition()->mBoxSizing),
+    nsCSSProps::ValueToKeywordEnum(StylePosition()->mBoxSizing,
                                    nsCSSProps::kBoxSizingKTable));
   return val.forget();
 }
@@ -6010,7 +6010,7 @@ nsComputedDOMStyle::CreatePrimitiveValueForClipPath(
 
   nsAutoString boxString;
   AppendASCIItoUTF16(
-    nsCSSProps::ValueToKeyword(uint8_t(aSizingBox),
+    nsCSSProps::ValueToKeyword(aSizingBox,
                                nsCSSProps::kClipShapeSizingKTable),
                                boxString);
   RefPtr<nsROCSSPrimitiveValue> val = new nsROCSSPrimitiveValue;