AK: Add reverse iterator as member

Author: https://github.com/guerinoni
Commit: https://github.com/SerenityOS/serenity/commit/0aed2f0f86
Pull-request: https://github.com/SerenityOS/serenity/pull/12741
Reviewed-by: https://github.com/IdanHo
Reviewed-by: https://github.com/awesomekling
Reviewed-by: https://github.com/linusg

AK/NonnullPtrVector.h

@@ -41,6 +41,11 @@ public:
     ALWAYS_INLINE constexpr Iterator end() { return Iterator::end(*this); }
     ALWAYS_INLINE constexpr ReverseIterator rend() { return ReverseIterator::rend(*this); }
 
+    ALWAYS_INLINE constexpr auto in_reverse()
+    {
+        return ReverseWrapper::in_reverse(*this);
+    }
+
     ALWAYS_INLINE PtrType& ptr_at(size_t index) { return Base::at(index); }
     ALWAYS_INLINE const PtrType& ptr_at(size_t index) const { return Base::at(index); }
 

AK/Vector.h

@@ -704,6 +704,11 @@ public:
     Iterator end() { return Iterator::end(*this); }
     ReverseIterator rend() { return ReverseIterator::rend(*this); }
 
+    ALWAYS_INLINE constexpr auto in_reverse()
+    {
+        return ReverseWrapper::in_reverse(*this);
+    }
+
     template<typename TUnaryPredicate>
     ConstIterator find_if(TUnaryPredicate&& finder) const
     {

Tests/AK/TestVector.cpp

@@ -567,4 +567,8 @@ TEST_CASE(reverse_range_for_loop)
     int index = 9;
     for (auto item : AK::ReverseWrapper::in_reverse(v))
         EXPECT_EQ(item, index--);
+
+    index = 9;
+    for (auto item : v.in_reverse())
+        EXPECT_EQ(item, index--);
 }