Merge branch 'staj_cursor' of https://github.com/danielaparker/jsoncons

Author: danielaparker

CHANGELOG.md

@@ -6,6 +6,15 @@ Performance Enhancement:
 - Use `std::from_chars` for chars to double conversion when 
 supported in GCC and VC.
 
+Enhancements:
+
+- Added a `size()` accessor function to `basic_staj_event`.
+If the event type is a `semantic_tag::key` or a `semantic_tag::string_value` or a `semantic_tag::byte_string_value`, 
+returns the size of the key or string or byte string value.
+If the event type is a `semantic_tag::begin_object` or a `semantic_tag::begin_array`, returns the size of the object
+or array if known, otherwise 0.
+For all other event types, returns 0.
+
 Changes:
 
 - For consistency with library naming conventions, the directory 

doc/ref/basic_staj_event.md

@@ -48,6 +48,13 @@ If `tag()` == `semantic_tag::ext`, returns a format specific tag associated with
 otherwise return 0. An example is a MessagePack `type` in the range 0-127 associated with the
 MessagePack ext format family, or a CBOR tag preceeding a byte string. 
 
+    size_t size() const
+If `event_type()` is a `staj_event_type::key` or a `staj_event_type::string_value` or a `staj_event_type::byte_string_value`, 
+returns the size of the key or string or byte string value.
+If `event_type()` is a `staj_event_type::begin_object` or a `staj_event_type::begin_array`, returns the size of the object
+or array if known, otherwise 0.
+For all other event types, returns 0.
+
     template <class T, class... Args>
     T get() const;
 Attempts to convert the json value to the template value type.

include/jsoncons/staj_cursor.hpp

@@ -160,6 +160,11 @@ class basic_staj_event
     {
     }
 
+    basic_staj_event(staj_event_type event_type, std::size_t length, semantic_tag tag = semantic_tag::none)
+        : event_type_(event_type), tag_(tag), ext_tag_(0), value_(), length_(length)
+    {
+    }
+
     basic_staj_event(null_type, semantic_tag tag)
         : event_type_(staj_event_type::null_value), tag_(tag), ext_tag_(0), value_(), length_(0)
     {
@@ -219,6 +224,11 @@ class basic_staj_event
         value_.byte_string_data_ = s.data();
     }
 
+    std::size_t size() const
+    {
+        return length_;
+    }
+
     template <class T>
     T get() const
     {
@@ -994,6 +1004,12 @@ class basic_staj_visitor : public basic_json_visitor<CharT>
         return !pred_(event_, context);
     }
 
+    bool visit_begin_object(std::size_t length, semantic_tag tag, const ser_context& context, std::error_code&) override
+    {
+        event_ = basic_staj_event<CharT>(staj_event_type::begin_object, length, tag);
+        return !pred_(event_, context);
+    }
+
     bool visit_end_object(const ser_context& context, std::error_code&) override
     {
         event_ = basic_staj_event<CharT>(staj_event_type::end_object);
@@ -1006,6 +1022,12 @@ class basic_staj_visitor : public basic_json_visitor<CharT>
         return !pred_(event_, context);
     }
 
+    bool visit_begin_array(std::size_t length, semantic_tag tag, const ser_context& context, std::error_code&) override
+    {
+        event_ = basic_staj_event<CharT>(staj_event_type::begin_array, length, tag);
+        return !pred_(event_, context);
+    }
+
     bool visit_end_array(const ser_context& context, std::error_code&) override
     {
         event_ = basic_staj_event<CharT>(staj_event_type::end_array);

test/cbor/src/cbor_cursor_tests.cpp

@@ -40,6 +40,7 @@ TEST_CASE("cbor_cursor reputon test")
         cbor::cbor_bytes_cursor cursor(data);
 
         CHECK(cursor.current().event_type() == staj_event_type::begin_object);
+        CHECK(cursor.current().size() == 2);
         cursor.next();
         CHECK(cursor.current().event_type() == staj_event_type::key);
         cursor.next();
@@ -48,6 +49,7 @@ TEST_CASE("cbor_cursor reputon test")
         CHECK(cursor.current().event_type() == staj_event_type::key);
         cursor.next();
         CHECK(cursor.current().event_type() == staj_event_type::begin_array);
+        CHECK(cursor.current().size() == 1);
         cursor.next();
         CHECK(cursor.current().event_type() == staj_event_type::begin_object);
         cursor.next();