direct parsing supports paths

Author: grisumbras

include/boost/json/detail/parse_into.hpp

@@ -1661,6 +1661,47 @@ class converting_handler<optional_conversion_tag, V, P>
 #undef BOOST_JSON_INVOKE_INNER
 };
 
+// path handler
+template< class V, class P >
+class converting_handler<path_conversion_tag, V, P>
+    : public scalar_handler<P, error::not_string>
+{
+private:
+    V* value_;
+    bool cleared_ = false;
+
+public:
+    converting_handler( V* v, P* p )
+        : converting_handler::scalar_handler(p)
+        , value_(v)
+    {}
+
+    bool on_string_part( error_code&, string_view sv )
+    {
+        if( !cleared_ )
+        {
+            cleared_ = true;
+            value_->clear();
+        }
+
+        value_->concat( sv.begin(), sv.end() );
+        return true;
+    }
+
+    bool on_string( error_code&, string_view sv )
+    {
+        if( !cleared_ )
+            value_->clear();
+        else
+            cleared_ = false;
+
+        value_->concat( sv.begin(), sv.end() );
+
+        this->parent_->signal_value();
+        return true;
+    }
+};
+
 // into_handler
 template< class V >
 class into_handler

test/parse_into.cpp

@@ -18,6 +18,10 @@
 #include <climits>
 #include <map>
 
+#ifndef BOOST_NO_CXX17_HDR_FILESYSTEM
+#include <filesystem>
+#endif // BOOST_NO_CXX17_HDR_FILESYSTEM
+
 #include "test.hpp"
 #include "test_suite.hpp"
 
@@ -414,6 +418,15 @@ class parse_into_test
 #endif
     }
 
+    void testPath()
+    {
+#ifndef BOOST_NO_CXX17_HDR_FILESYSTEM
+        testParseInto< std::filesystem::path >( "c:/" );
+        testParseInto< std::filesystem::path >( ".." );
+        testParseInto< std::filesystem::path >( "../" );
+#endif // BOOST_NO_CXX17_HDR_FILESYSTEM
+    }
+
     void run()
     {
         testNull();
@@ -427,10 +440,12 @@ class parse_into_test
         testStruct();
         testEnum();
         testOptional();
+        testPath();
         testVariant<variant2::variant, variant2::monostate>();
 #ifndef BOOST_NO_CXX17_HDR_VARIANT
         testVariant<std::variant, std::monostate>();
 #endif
+
         {
             int n;
             BOOST_TEST_THROWS_WITH_LOCATION( parse_into( n, "null" ) );