Bug 1400307 - handle char32_t in TypeTraits.h; r=froydnj

This adds a couple of missing char32_t specializations to TypeTraits.h,
and adds a few extra type traits tests besides.

MozReview-Commit-ID: 7aIJbZ2Ppka

--HG--
extra : rebase_source : 39ba985c4cc7ced3c667c6fc32c015e0389b1fd2

mfbt/TypeTraits.h

@@ -99,6 +99,7 @@ template<> struct IsIntegralHelper<unsigned long long> : TrueType {};
 template<> struct IsIntegralHelper<bool>               : TrueType {};
 template<> struct IsIntegralHelper<wchar_t>            : TrueType {};
 template<> struct IsIntegralHelper<char16_t>           : TrueType {};
+template<> struct IsIntegralHelper<char32_t>           : TrueType {};
 
 } /* namespace detail */
 
@@ -440,6 +441,7 @@ template<> struct IsPod<float>              : TrueType {};
 template<> struct IsPod<double>             : TrueType {};
 template<> struct IsPod<wchar_t>            : TrueType {};
 template<> struct IsPod<char16_t>           : TrueType {};
+template<> struct IsPod<char32_t>           : TrueType {};
 template<typename T> struct IsPod<T*>       : TrueType {};
 
 namespace detail {

mfbt/tests/TestTypeTraits.cpp

@@ -26,7 +26,9 @@ using mozilla::IsConvertible;
 using mozilla::IsDefaultConstructible;
 using mozilla::IsDestructible;
 using mozilla::IsEmpty;
+using mozilla::IsIntegral;
 using mozilla::IsLvalueReference;
+using mozilla::IsPod;
 using mozilla::IsPointer;
 using mozilla::IsReference;
 using mozilla::IsRvalueReference;
@@ -52,6 +54,39 @@ static_assert(IsArray<bool[]>::value,
 static_assert(IsArray<bool[5]>::value,
               "bool[5] is an array");
 
+static_assert(IsIntegral<char16_t>::value,
+              "char16_t is integral");
+static_assert(IsIntegral<char32_t>::value,
+              "char32_t is integral");
+static_assert(!IsIntegral<char&>::value,
+              "char& is not integral");
+static_assert(!IsIntegral<double>::value,
+              "double is not integral");
+
+static_assert(IsPod<bool>::value,
+              "bool is pod");
+static_assert(IsPod<char16_t>::value,
+              "char16_t is pod");
+static_assert(IsPod<char32_t>::value,
+              "char32_t is pod");
+struct YepItsAPod { int x; };
+static_assert(!IsPod<YepItsAPod>::value,
+              "pod struct is pod");
+struct NopeItsNotAPod {
+  int x;
+ protected:
+  int y;
+};
+static_assert(!IsPod<NopeItsNotAPod>::value,
+              "non-standard-layout struct is not pod");
+struct NopeStillNotAPod {
+  NopeStillNotAPod() : x(7) { }
+  int x;
+};
+static_assert(!IsPod<NopeStillNotAPod>::value,
+              "struct with constructor is not pod");
+
+
 static_assert(!IsPointer<bool>::value,
               "bool not a pointer");
 static_assert(IsPointer<bool*>::value,