Make Result : evmc_result inheritance public

This allows accessing evmc::Result via reference to evmc_result.

Author: yperbasis

include/evmc/evmc.hpp

@@ -328,7 +328,7 @@ constexpr auto make_result = evmc_make_result;
 ///
 /// This is a RAII wrapper for evmc_result and objects of this type
 /// automatically release attached resources.
-class Result : private evmc_result
+class Result : public evmc_result
 {
 public:
     using evmc_result::create_address;

test/unittests/cpp_test.cpp

@@ -973,3 +973,26 @@ TEST(cpp, revision_to_string_invalid)
         EXPECT_EQ(os.str(), "<unknown>");
     }
 }
+
+TEST(cpp, result_c_const_access)
+{
+    static constexpr auto get_gas_left = [](const evmc_result& c_result) noexcept{
+        return c_result.gas_left;
+    };
+
+    evmc::Result r;
+    r.gas_left = 1;
+    EXPECT_EQ(get_gas_left(r), 1);
+}
+
+TEST(cpp, result_c_nonconst_access)
+{
+    static constexpr auto reset_gas_left = [](evmc_result& c_result) noexcept{
+        c_result.gas_left = 0;
+    };
+
+    evmc::Result r;
+    r.gas_left = 1;
+    reset_gas_left(r);
+    EXPECT_EQ(r.gas_left, 0);
+}