Enhance byte_string_view

Author: danielaparker

doc/ref/byte_string_view.md

@@ -31,9 +31,9 @@ Member type                         |Definition
     template <class Container>
     constexpr explicit byte_string_view(const Container& cont); 
 
-    byte_string_view(const byte_string_view&) noexcept = default;
+    constexpr byte_string_view(const byte_string_view&) noexcept = default;
 
-    byte_string_view(byte_string_view&& other) noexcept;
+    constexpr byte_string_view(byte_string_view&& other) noexcept;
 
 #### Assignment
 
@@ -43,19 +43,23 @@ Member type                         |Definition
 
 #### Iterators
 
-    const_iterator begin() const noexcept;
+    constexpr const_iterator begin() const noexcept;
 
-    const_iterator end() const noexcept;
+    constexpr const_iterator end() const noexcept;
+
+    constexpr const_iterator cbegin() const noexcept;
+
+    constexpr const_iterator cend() const noexcept;
 
 #### Element access
 
     constexpr const uint8_t* data() const noexcept;
 
-    uint8_t operator[](size_type pos) const; 
+    constexpr uint8_t operator[](size_type pos) const; 
 
-    byte_string_view substr(size_type pos) const;
+    constexpr byte_string_view substr(size_type pos) const;
 
-    byte_string_view substr(size_type pos, size_type n) const;
+    constexpr byte_string_view substr(size_type pos, size_type n) const;
 
 #### Capacity
 

include/jsoncons/byte_string.hpp

@@ -332,7 +332,7 @@ namespace jsoncons {
         using traits_type = byte_traits;
 
         using const_iterator = const uint8_t*;
-        using iterator = const uint8_t*;
+        using iterator = const_iterator;
         using size_type = std::size_t;
         using value_type = uint8_t;
         using reference = uint8_t&;
@@ -363,11 +363,16 @@ namespace jsoncons {
 
         constexpr byte_string_view(const byte_string_view&) noexcept = default;
 
-        byte_string_view(byte_string_view&& other) noexcept
+        JSONCONS_CPP14_CONSTEXPR byte_string_view(byte_string_view&& other) noexcept
             : data_(nullptr), size_(0)
         {
-            std::swap(data_, other.data_);
-            std::swap(size_, other.size_);
+            const_pointer temp_data = data_;
+            data_ = other.data_;
+            other.data_ = temp_data;
+
+            size_type temp_size = size_;
+            size_ = other.size_;
+            other.size_ = temp_size;
         }
 
         byte_string_view& operator=(const byte_string_view&) = default;
@@ -396,21 +401,29 @@ namespace jsoncons {
         }
 
         // iterator support 
-        const_iterator begin() const noexcept
+        constexpr const_iterator begin() const noexcept
         {
             return data_;
         }
-        const_iterator end() const noexcept
+        constexpr const_iterator end() const noexcept
+        {
+            return data_ + size_;
+        }
+        constexpr const_iterator cbegin() const noexcept
+        {
+            return data_;
+        }
+        constexpr const_iterator cend() const noexcept
         {
             return data_ + size_;
         }
 
-        uint8_t operator[](size_type pos) const 
+        constexpr uint8_t operator[](size_type pos) const 
         { 
             return data_[pos]; 
         }
 
-        byte_string_view substr(size_type pos) const 
+        JSONCONS_CPP14_CONSTEXPR byte_string_view substr(size_type pos) const 
         {
             if (pos > size_)
             {

tests/src/byte_string_tests.cpp

@@ -110,6 +110,45 @@ TEST_CASE("byte_string_view constructors")
     {
         std::vector<uint8_t> v = {'f','o','o','b','a','r'};
         byte_string_view bstr(v);
+        CHECK(bstr[0] == 'f');
+        CHECK(bstr[1] == 'o');
+        CHECK(bstr[2] == 'o');
+        CHECK(bstr[3] == 'b');
+        CHECK(bstr[4] == 'a');
+        CHECK(bstr[5] == 'r');
+
+        byte_string_view copied(bstr);
+        CHECK(copied == bstr);
+
+        byte_string_view moved(std::move(bstr));
+        CHECK(bstr.data() == nullptr);
+        CHECK(bstr.size() == 0);
+
+        REQUIRE(moved.size() == 6);
+        CHECK(moved[0] == 'f');
+        CHECK(moved[1] == 'o');
+        CHECK(moved[2] == 'o');
+        CHECK(moved[3] == 'b');
+        CHECK(moved[4] == 'a');
+        CHECK(moved[5] == 'r');
+    }
+}
+
+TEST_CASE("byte_string_view iterators")
+{
+    SECTION("begin/end")
+    {
+        std::vector<uint8_t> v = {'f','o','o'};
+        byte_string_view bstr(v);
+
+        auto it = bstr.begin();
+        REQUIRE(it != bstr.end());
+        CHECK(*it++ == 'f');
+        REQUIRE(it != bstr.end());
+        CHECK(*it++ == 'o');
+        REQUIRE(it != bstr.end());
+        CHECK(*it++ == 'o');
+        CHECK(it == bstr.end());
     }
 }