Add @@hasInstance Symbol support for instanceof operator (#3226)

Implemented ES2015 modifications for `instanceof` operator.

JerryScript-DCO-1.0-Signed-off-by: Peter Gal pgal.u-szeged@partner.samsung.com
JerryScript-DCO-1.0-Signed-off-by: Dániel Vince vinced@inf.u-szeged.hu

jerry-core/vm/opcodes-ecma-relational-equality.c

@@ -16,6 +16,7 @@
 #include "ecma-comparison.h"
 #include "ecma-conversion.h"
 #include "ecma-exceptions.h"
+#include "ecma-function-object.h"
 #include "ecma-helpers.h"
 #include "ecma-objects.h"
 #include "ecma-try-catch-macro.h"
@@ -109,6 +110,32 @@ opfunc_instanceof (ecma_value_t left_value, /**< left value */
     return ecma_raise_type_error (ECMA_ERR_MSG ("Expected an object in 'instanceof' check."));
   }
 
+#if ENABLED (JERRY_ES2015_BUILTIN_SYMBOL)
+  ecma_value_t has_instance_method = ecma_op_get_method_by_symbol_id (right_value, LIT_MAGIC_STRING_HAS_INSTANCE);
+  if (ECMA_IS_VALUE_ERROR (has_instance_method))
+  {
+    return has_instance_method;
+  }
+
+  if (JERRY_UNLIKELY (!ecma_is_value_undefined (has_instance_method)))
+  {
+    ecma_object_t *method_obj_p = ecma_get_object_from_value (has_instance_method);
+    ecma_value_t has_instance_result = ecma_op_function_call (method_obj_p, right_value, &left_value, 1);
+
+    ecma_free_value (has_instance_method);
+
+    if (ECMA_IS_VALUE_ERROR (has_instance_result))
+    {
+      return has_instance_result;
+    }
+
+    bool has_instance = ecma_op_to_boolean (has_instance_result);
+    ecma_free_value (has_instance_result);
+
+    return ecma_make_boolean_value (has_instance);
+  }
+#endif /* ENABLED (JERRY_ES2015_BUILTIN_SYMBOL) */
+
   ecma_object_t *right_value_obj_p = ecma_get_object_from_value (right_value);
   return ecma_op_object_has_instance (right_value_obj_p, left_value);
 } /* opfunc_instanceof */