Make wxVector reverse iterators conform to iterator requirements

This is similar to a recent commit adding the missing typedefs to wxList
iterators and defines the types required by the iterator concept in
wxVector::reverse_iterator and const_reverse_iterator classes (simple
iterators are just pointers and are already covered by the standard
iterator_traits specialization).

docs/changes.txt

@@ -69,7 +69,7 @@ Changes in behaviour which may result in build errors
 
 All:
 
-- Make wxList iterators conform to input iterator requirements.
+- Make wxList and wxVector iterators conform to input iterator requirements.
 
 
 3.1.1: (released 2018-02-19)

include/wx/vector.h

@@ -33,6 +33,9 @@ inline void wxVectorSort(wxVector<T>& v)
 #include "wx/meta/if.h"
 
 #include "wx/beforestd.h"
+#if wxUSE_STD_CONTAINERS_COMPATIBLY
+#include <iterator>
+#endif
 #include <new> // for placement new
 #include "wx/afterstd.h"
 
@@ -172,6 +175,14 @@ public:
     class reverse_iterator
     {
     public:
+#if wxUSE_STD_CONTAINERS_COMPATIBLY
+        typedef std::random_access_iterator_tag iterator_category;
+#endif
+        typedef ptrdiff_t difference_type;
+        typedef T value_type;
+        typedef value_type* pointer;
+        typedef value_type& reference;
+
         reverse_iterator() : m_ptr(NULL) { }
         explicit reverse_iterator(iterator it) : m_ptr(it) { }
         reverse_iterator(const reverse_iterator& it) : m_ptr(it.m_ptr) { }
@@ -218,6 +229,14 @@ public:
     class const_reverse_iterator
     {
     public:
+#if wxUSE_STD_CONTAINERS_COMPATIBLY
+        typedef std::random_access_iterator_tag iterator_category;
+#endif
+        typedef ptrdiff_t difference_type;
+        typedef T value_type;
+        typedef const value_type* pointer;
+        typedef const value_type& reference;
+
         const_reverse_iterator() : m_ptr(NULL) { }
         explicit const_reverse_iterator(const_iterator it) : m_ptr(it) { }
         const_reverse_iterator(const reverse_iterator& it) : m_ptr(it.m_ptr) { }

tests/vectors/vectors.cpp

@@ -22,6 +22,10 @@
 
 #include "wx/vector.h"
 
+#if wxUSE_STD_CONTAINERS_COMPATIBLY
+    #include <vector>
+#endif // wxUSE_STD_CONTAINERS_COMPATIBLY
+
 // ----------------------------------------------------------------------------
 // simple class capable of detecting leaks of its objects
 // ----------------------------------------------------------------------------
@@ -360,6 +364,13 @@ TEST_CASE("wxVector::reverse_iterator", "[vector][reverse_iterator]")
     ri = rb + 2;
     CHECK( ri - rb == 2 );
     CHECK( re - ri == 8 );
+
+#if wxUSE_STD_CONTAINERS_COMPATIBLY
+    std::vector<int> stdvec(rb, re);
+    REQUIRE( stdvec.size() == 10 );
+    CHECK( stdvec[0] == 10 );
+    CHECK( stdvec[9] == 1 );
+#endif // wxUSE_STD_CONTAINERS_COMPATIBLY
 }
 
 TEST_CASE("wxVector::capacity", "[vector][capacity][shrink_to_fit]")