added test cases

ChangeLog.md

@@ -5,10 +5,12 @@ All notable changes to this project will be documented in this file. This projec
 
 [Full Changelog](https://github.com/nlohmann/json/compare/v1.1.0...HEAD)
 
+- Additional integration options [\#237](https://github.com/nlohmann/json/issues/237)
+- Can't use basic\_json::iterator as a base iterator for std::move\_iterator [\#233](https://github.com/nlohmann/json/issues/233)
 - Provide a FAQ [\#163](https://github.com/nlohmann/json/issues/163)
 - Create PULL\_REQUEST\_TEMPLATE.md [\#213](https://github.com/nlohmann/json/pull/213) ([whackashoe](https://github.com/whackashoe))
 - fixed noexcept; added constexpr [\#208](https://github.com/nlohmann/json/pull/208) ([nlohmann](https://github.com/nlohmann))
-- Add support for afl-fuzz testing [\#207](https://github.com/nlohmann/json/pull/207) ([msm-](https://github.com/msm-))
+- Add support for afl-fuzz testing [\#207](https://github.com/nlohmann/json/pull/207) ([mykter](https://github.com/mykter))
 - Issue \#178 - Extending support to full uint64\_t/int64\_t range and unsigned type \(updated\) [\#193](https://github.com/nlohmann/json/pull/193) ([twelsby](https://github.com/twelsby))
 
 - double values are serialized with commas as decimal points [\#228](https://github.com/nlohmann/json/issues/228)
@@ -26,6 +28,7 @@ All notable changes to this project will be documented in this file. This projec
 - Conflicting typedef of ssize\_t on Windows 32 bit when using Boost.Python [\#204](https://github.com/nlohmann/json/issues/204)
 - Integer conversion to unsigned [\#178](https://github.com/nlohmann/json/issues/178)
 
+- Implement additional integration options [\#238](https://github.com/nlohmann/json/pull/238) ([robertmrk](https://github.com/robertmrk))
 - make serialization locale-independent [\#232](https://github.com/nlohmann/json/pull/232) ([nlohmann](https://github.com/nlohmann))
 - fixes \#223 by updating README.md [\#227](https://github.com/nlohmann/json/pull/227) ([kevin--](https://github.com/kevin--))
 - Use namespace std for int64\_t and uint64\_t [\#226](https://github.com/nlohmann/json/pull/226) ([lv-zheng](https://github.com/lv-zheng))

doc/examples/json_pointer__to_string.cpp

+#include <json.hpp>
+
+using json = nlohmann::json;
+
+int main()
+{
+    // different JSON Pointers
+    json::json_pointer ptr1("");
+    json::json_pointer ptr2("/foo");
+    json::json_pointer ptr3("/foo/0");
+    json::json_pointer ptr4("/");
+    json::json_pointer ptr5("/a~1b");
+    json::json_pointer ptr6("/c%d");
+    json::json_pointer ptr7("/e^f");
+    json::json_pointer ptr8("/g|h");
+    json::json_pointer ptr9("/i\\j");
+    json::json_pointer ptr10("/k\"l");
+    json::json_pointer ptr11("/ ");
+    json::json_pointer ptr12("/m~0n");
+
+
+    std::cout << ptr1.to_string() << '\n'
+              << ptr2.to_string() << '\n'
+              << ptr3.to_string() << '\n'
+              << ptr4.to_string() << '\n'
+              << ptr5.to_string() << '\n'
+              << ptr6.to_string() << '\n'
+              << ptr7.to_string() << '\n'
+              << ptr8.to_string() << '\n'
+              << ptr9.to_string() << '\n'
+              << ptr10.to_string() << '\n'
+              << ptr11.to_string() << '\n'
+              << ptr12.to_string() << std::endl;
+}

doc/examples/json_pointer__to_string.link

+<a target="_blank" href="http://melpon.org/wandbox/permlink/O4FbKx0TbZioFhfU"><b>online</b></a>
\ No newline at end of file

doc/examples/json_pointer__to_string.output

+
+/foo
+/foo/0
+/
+/a~1b
+/c%d
+/e^f
+/g|h
+/i\j
+/k"l
+/ 
+/m~0n

src/json.hpp

@@ -8818,6 +8818,10 @@ basic_json_parser_63:
     /*!
     @brief JSON Pointer
 
+    A JSON pointer defines a string syntax for identifying a specific value
+    within a JSON document. It can be used with functions `at` and
+    `operator[]`. Furthermore, JSON pointers are the base for JSON patches.
+
     @sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
 
     @since version 2.0.0
@@ -8854,10 +8858,37 @@ basic_json_parser_63:
             : reference_tokens(split(s))
         {}
 
-        /// test for inequality
-        bool operator!=(const json_pointer& rhs) const
+        /*!
+        @brief return a string representation of the JSON pointer
+
+        @invariant For each JSON pointer `ptr`, it holds:
+        @code {.cpp}
+        ptr == json_pointer(ptr.to_string());
+        @endcode
+
+        @return a string representation of the JSON pointer
+
+        @liveexample{The example shows the result of `to_string`.,
+        json_pointer__to_string}
+
+        @since version 2.0.0
+        */
+        std::string to_string() const noexcept
+        {
+            std::string result;
+
+            for (const auto& reference_token : reference_tokens)
+            {
+                result += "/" + escape(reference_token);
+            }
+
+            return result;
+        }
+
+        /// @copydoc to_string()
+        operator std::string() const
         {
-            return reference_tokens != rhs.reference_tokens;
+            return to_string();
         }
 
       private:

src/json.hpp.re2c

@@ -8128,6 +8128,10 @@ class basic_json
     /*!
     @brief JSON Pointer
 
+    A JSON pointer defines a string syntax for identifying a specific value
+    within a JSON document. It can be used with functions `at` and
+    `operator[]`. Furthermore, JSON pointers are the base for JSON patches.
+
     @sa [RFC 6901](https://tools.ietf.org/html/rfc6901)
 
     @since version 2.0.0
@@ -8164,10 +8168,37 @@ class basic_json
             : reference_tokens(split(s))
         {}
 
-        /// test for inequality
-        bool operator!=(const json_pointer& rhs) const
+        /*!
+        @brief return a string representation of the JSON pointer
+
+        @invariant For each JSON pointer `ptr`, it holds:
+        @code {.cpp}
+        ptr == json_pointer(ptr.to_string());
+        @endcode
+
+        @return a string representation of the JSON pointer
+
+        @liveexample{The example shows the result of `to_string`.,
+        json_pointer__to_string}
+
+        @since version 2.0.0
+        */
+        std::string to_string() const noexcept
+        {
+            std::string result;
+
+            for (const auto& reference_token : reference_tokens)
+            {
+                result += "/" + escape(reference_token);
+            }
+
+            return result;
+        }
+
+        /// @copydoc to_string()
+        operator std::string() const
         {
-            return reference_tokens != rhs.reference_tokens;
+            return to_string();
         }
 
       private:

test/unit.cpp

@@ -12035,6 +12035,36 @@ TEST_CASE("Unicode", "[hide]")
 
         // the array has 1112064 + 1 elemnts (a terminating "null" value)
         CHECK(j.size() == 1112065);
+
+        SECTION("check JSON Pointers")
+        {
+            for (auto s : j)
+            {
+                // skip non-string JSON values
+                if (not s.is_string())
+                {
+                    continue;
+                }
+
+                std::string ptr = s;
+
+                // tilde must be followed by 0 or 1
+                if (ptr == "~")
+                {
+                    ptr += "0";
+                }
+
+                // JSON Pointers must begin with "/"
+                ptr = "/" + ptr;
+
+                CHECK_NOTHROW(json::json_pointer("/" + ptr));
+
+                // check escape/unescape roundtrip
+                auto escaped = json::json_pointer::escape(ptr);
+                json::json_pointer::unescape(escaped);
+                CHECK(escaped == ptr);
+            }
+        }
     }
 
     SECTION("ignore byte-order-mark")
@@ -12389,6 +12419,17 @@ TEST_CASE("JSON pointers")
         json j_object(json::value_t::object);
         CHECK(j_object.flatten().unflatten() == json());
     }
+
+    SECTION("string representation")
+    {
+        for (auto ptr :
+                {"", "/foo", "/foo/0", "/", "/a~1b", "/c%d", "/e^f", "/g|h", "/i\\j", "/k\"l", "/ ", "/m~0n"
+                })
+        {
+            CHECK(json::json_pointer(ptr).to_string() == ptr);
+            CHECK(json::json_pointer(ptr) == ptr);
+        }
+    }
 }
 
 TEST_CASE("JSON patch")