Added new 'jerry_value_instanceof' API function.

JerryScript-DCO-1.0-Signed-off-by: László Langó [email protected]

Author: LaszloLango

docs/02.API-REFERENCE.md

@@ -1084,6 +1084,84 @@ jerry_get_global_object (void);
 
 Functions to check the type of an API value ([jerry_value_t](#jerry_value_t)).
 
+
+## jerry_value_instanceof
+
+**Summary**
+
+Returns whether the given `jerry_value_t` is an instance of the given prototype.
+
+**Prototype**
+
+```c
+jerry_value_t
+jerry_value_instanceof (const jerry_value_t value, const jerry_value_t prototype);
+```
+
+- `value` - api value of instance object
+- `prototype` - api value of prototype
+- return value
+  - error, if value argument is not an object or prototype argument is not a function
+  - true, if the specified value is an instance of the given prototype
+  - false, otherwise
+
+**Example**
+
+[doctest]: # ()
+
+```c
+#include "jerryscript.h"
+
+static jerry_value_t
+my_constructor (const jerry_value_t func_val,
+                const jerry_value_t this_val,
+                const jerry_value_t argv[],
+                const jerry_length_t argc)
+{
+  return jerry_create_undefined ();
+}
+
+int
+main (void)
+{
+  jerry_init (JERRY_INIT_EMPTY);
+
+  jerry_value_t base_obj = jerry_create_object ();
+  jerry_value_t constructor = jerry_create_external_function (my_constructor);
+
+  /* External functions does not have a prototype by default, so we need to create one */
+  jerry_value_t prototype_str = jerry_create_string ((const jerry_char_t *) ("prototype"));
+  jerry_release_value (jerry_set_property (constructor, prototype_str, base_obj));
+  jerry_release_value (prototype_str);
+
+  /* Construct the instance. */
+  jerry_value_t instance_val = jerry_construct_object (constructor, NULL, 0);
+
+  /* Call the API function of 'instanceof'. */
+  jerry_value_t is_instance = jerry_value_instanceof (instance_val, constructor);
+  if (!jerry_value_is_error (is_instance)
+      && jerry_get_boolean_value (is_instance) == true)
+  {
+    /* ... */
+  }
+
+  /* Free all of the jerry values and cleanup the engine. */
+  jerry_release_value (base_obj);
+  jerry_release_value (constructor);
+  jerry_release_value (instance_val);
+  jerry_release_value (is_instance);
+
+  jerry_cleanup ();
+  return 0;
+}
+```
+
+**See also**
+
+- [jerry_construct_object](#jerry_construct_object)
+- [jerry_create_external_function](#jerry_create_external_function)
+
+
 ## jerry_value_is_abort
 
 **Summary**

jerry-core/api/jerry.c

@@ -601,6 +601,40 @@ jerry_get_global_object (void)
   return ecma_make_object_value (global_obj_p);
 } /* jerry_get_global_object */
 
+/**
+ * Check if the specified value is an instance of the given prototype.
+ *
+ * See also ECMA-262 v5.1, 11.8.6
+ *
+ * Note:
+ *      returned value must be freed with jerry_release_value, when it is no longer needed.
+ *
+ * @return true  - if the specified value is an instance of the given prototype
+ *         false - otherwise
+ *         error - if value argument is not an object or prototype argument is not a function.
+ *
+ */
+jerry_value_t
+jerry_value_instanceof (const jerry_value_t value, /**< object value */
+                        const jerry_value_t prototype) /**< prototpye function */
+{
+  jerry_assert_api_available ();
+
+  if (ecma_is_value_error_reference (value))
+  {
+    return jerry_throw (ecma_raise_type_error (ECMA_ERR_MSG (error_value_msg_p)));
+  }
+
+  if (!ecma_is_value_object (value)
+      || !ecma_op_is_callable (prototype))
+  {
+    return jerry_throw (ecma_raise_type_error (ECMA_ERR_MSG (wrong_args_msg_p)));
+  }
+
+  ecma_object_t *proto_obj_p = ecma_get_object_from_value (prototype);
+  return jerry_return (ecma_op_object_has_instance (proto_obj_p, value));
+} /* jerry_value_instanceof */
+
 /**
  * Check if the specified value is an abort value.
  *

jerry-core/ecma/operations/ecma-function-object.c

@@ -327,7 +327,8 @@ ecma_op_arrow_function_get_compiled_code (ecma_arrow_function_t *arrow_function_
 /**
  * 15.3.5.3 implementation of [[HasInstance]] for Function objects
  *
- * @return ecma value
+ * @return true/false - if arguments are valid
+ *         error - otherwise
  *         Returned value must be freed with ecma_free_value
  */
 ecma_value_t

jerry-core/include/jerryscript-core.h

@@ -343,6 +343,8 @@ jerry_value_t jerry_get_global_object (void);
 /**
  * Checker functions of 'jerry_value_t'.
  */
+jerry_value_t jerry_value_instanceof(const jerry_value_t value,
+                                     const jerry_value_t prototype);
 bool jerry_value_is_abort (const jerry_value_t value);
 bool jerry_value_is_array (const jerry_value_t value);
 bool jerry_value_is_boolean (const jerry_value_t value);

tests/unit-core/test-api-instaceof.c

@@ -0,0 +1,104 @@
+/* Copyright JS Foundation and other contributors, http://js.foundation
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jerryscript.h"
+
+#include "test-common.h"
+
+static jerry_value_t
+my_constructor (const jerry_value_t func_val, /**< function */
+                const jerry_value_t this_val, /**< this */
+                const jerry_value_t argv[], /**< arguments */
+                const jerry_length_t argc) /**< number of arguments */
+{
+  (void) func_val;
+  (void) this_val;
+  (void) argv;
+  (void) argc;
+  return jerry_create_undefined ();
+} /* my_constructor */
+
+int
+main (void)
+{
+  TEST_INIT ();
+
+  jerry_init (JERRY_INIT_EMPTY);
+
+  jerry_value_t base_obj = jerry_create_object ();
+  jerry_value_t constructor = jerry_create_external_function (my_constructor);
+
+  jerry_value_t no_proto_instance_val = jerry_construct_object (constructor, NULL, 0);
+
+  jerry_value_t prototype_str = jerry_create_string ((const jerry_char_t *) ("prototype"));
+  jerry_value_t res = jerry_set_property (constructor, prototype_str, base_obj);
+  jerry_release_value (prototype_str);
+  TEST_ASSERT (!jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  jerry_value_t instance_val = jerry_construct_object (constructor, NULL, 0);
+
+  /* Test the correct call */
+  res = jerry_value_instanceof (instance_val, constructor);
+  TEST_ASSERT (!jerry_value_is_error (res));
+  TEST_ASSERT (jerry_get_boolean_value (res));
+  jerry_release_value (res);
+
+  /* Test instance with different prototype */
+  res = jerry_value_instanceof (no_proto_instance_val, constructor);
+  TEST_ASSERT (!jerry_value_is_error (res));
+  TEST_ASSERT (!jerry_get_boolean_value (res));
+  jerry_release_value (res);
+
+  /* Test wrong argument order */
+  res = jerry_value_instanceof (constructor, instance_val);
+  TEST_ASSERT (jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  /* Test wrong arguments */
+  res = jerry_value_instanceof (base_obj, constructor);
+  TEST_ASSERT (!jerry_value_is_error (res));
+  TEST_ASSERT (!jerry_get_boolean_value (res));
+  jerry_release_value (res);
+
+  /* Test value is not an object */
+  res = jerry_value_instanceof (jerry_create_undefined (), constructor);
+  TEST_ASSERT (jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  /* Test prototype is not a function object */
+  res = jerry_value_instanceof (instance_val, jerry_create_undefined ());
+  TEST_ASSERT (jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  res = jerry_value_instanceof (instance_val, base_obj);
+  TEST_ASSERT (jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  /* Test error argument */
+  jerry_value_t error = jerry_create_error_from_value (base_obj, true);
+  res = jerry_value_instanceof (error, constructor);
+  TEST_ASSERT (jerry_value_is_error (res));
+  jerry_release_value (res);
+
+  jerry_release_value (error);
+  jerry_release_value (constructor);
+  jerry_release_value (instance_val);
+  jerry_release_value (no_proto_instance_val);
+
+  jerry_cleanup ();
+
+  return 0;
+} /* main */