Implement Iterator interface and Array iterators (#2640)

JerryScript-DCO-1.0-Signed-off-by: Robert Fancsik [email protected]

Author: rerobika

jerry-core/config.h

@@ -41,6 +41,7 @@
 # define CONFIG_DISABLE_ES2015_CLASS
 # define CONFIG_DISABLE_ES2015_FUNCTION_PARAMETER_INITIALIZER
 # define CONFIG_DISABLE_ES2015_FUNCTION_REST_PARAMETER
+# define CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
 # define CONFIG_DISABLE_ES2015_MAP_BUILTIN
 # define CONFIG_DISABLE_ES2015_OBJECT_INITIALIZER
 # define CONFIG_DISABLE_ES2015_PROMISE_BUILTIN

jerry-core/ecma/base/ecma-gc.c

@@ -369,6 +369,12 @@ ecma_gc_mark (ecma_object_t *object_p) /**< object to mark from */
             break;
           }
 #endif /* !CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN */
+#ifndef CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
+          case ECMA_PSEUDO_ARRAY_ITERATOR:
+          {
+            break;
+          }
+#endif /* !CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN */
           default:
           {
             JERRY_ASSERT (ext_object_p->u.pseudo_array.type == ECMA_PSEUDO_ARRAY_ARGUMENTS);
@@ -762,6 +768,13 @@ ecma_gc_free_object (ecma_object_t *object_p) /**< object to free */
           return;
         }
 #endif /* !CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN */
+#ifndef CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
+        case ECMA_PSEUDO_ARRAY_ITERATOR:
+        {
+          ecma_dealloc_extended_object (object_p, sizeof (ecma_extended_object_t));
+          return;
+        }
+#endif /* !CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN */
         default:
         {
           JERRY_ASSERT (ext_object_p->u.pseudo_array.type == ECMA_PSEUDO_ARRAY_ARGUMENTS);

jerry-core/ecma/base/ecma-globals.h

@@ -664,8 +664,9 @@ typedef enum
   ECMA_PSEUDO_ARRAY_ARGUMENTS = 0, /**< Arguments object (10.6) */
   ECMA_PSEUDO_ARRAY_TYPEDARRAY = 1, /**< TypedArray which does NOT need extra space to store length and offset */
   ECMA_PSEUDO_ARRAY_TYPEDARRAY_WITH_INFO = 2, /**< TypedArray which NEEDS extra space to store length and offset */
+  ECMA_PSEUDO_ARRAY_ITERATOR = 3, /**< Array iterator object (ECMAScript v6, 22.1.5.1) */
 
-  ECMA_PSEUDO_ARRAY__MAX = ECMA_PSEUDO_ARRAY_TYPEDARRAY_WITH_INFO /**< maximum value */
+  ECMA_PSEUDO_ARRAY__MAX = ECMA_PSEUDO_ARRAY_ITERATOR /**< maximum value */
 } ecma_pseudo_array_type_t;
 
 /**
@@ -686,6 +687,18 @@ typedef enum
   ECMA_LEXICAL_ENVIRONMENT_TYPE__MAX = ECMA_LEXICAL_ENVIRONMENT_SUPER_OBJECT_BOUND /**< maximum value */
 } ecma_lexical_environment_type_t;
 
+#ifndef CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
+/**
+ * Types of array iterators.
+ */
+typedef enum
+{
+  ECMA_ARRAY_ITERATOR_KEYS, /**< List only key indices */
+  ECMA_ARRAY_ITERATOR_VALUES, /**< List only key values */
+  ECMA_ARRAY_ITERATOR_KEYS_VALUES, /**< List key indices and values */
+} ecma_array_iterator_type_t;
+#endif /* !CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN */
+
 /**
  * Offset for JERRY_CONTEXT (status_flags) top 8 bits.
  */
@@ -846,18 +859,21 @@ typedef struct
      */
     struct
     {
-      uint8_t type; /**< pseudo array type, e.g. Arguments, TypedArray*/
+      uint8_t type; /**< pseudo array type, e.g. Arguments, TypedArray, ArrayIterator */
       uint8_t extra_info; /**< extra information about the object.
-                           *   e.g. element_width_shift for typed arrays */
+                           *   e.g. element_width_shift for typed arrays,
+                           *        [[IterationKind]] property for %Iterator% */
       union
       {
         uint16_t length; /**< for arguments: length of names */
         uint16_t class_id; /**< for typedarray: the specific class name */
+        uint16_t iterator_index; /**< for %Iterator%: [[%Iterator%NextIndex]] property */
       } u1;
       union
       {
         ecma_value_t lex_env_cp; /**< for arguments: lexical environment */
         ecma_value_t arraybuffer; /**< for typedarray: internal arraybuffer */
+        ecma_value_t iterated_value_cp; /**< for %Iterator%: [[IteratedObject]] property */
       } u2;
     } pseudo_array;
 

jerry-core/ecma/builtin-objects/ecma-builtin-array-iterator-prototype.c

@@ -0,0 +1,193 @@
+/* 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 "ecma-builtin-helpers.h"
+#include "ecma-builtins.h"
+#include "ecma-iterator-object.h"
+#include "ecma-typedarray-object.h"
+
+#ifndef CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
+
+#ifdef CONFIG_DISABLE_ES2015_SYMBOL_BUILTIN
+#error "Iterator builtin requires ES2015 symbol builtin"
+#endif /* CONFIG_DISABLE_ES2015_SYMBOL_BUILTIN */
+
+#define ECMA_BUILTINS_INTERNAL
+#include "ecma-builtins-internal.h"
+
+#define BUILTIN_INC_HEADER_NAME "ecma-builtin-array-iterator-prototype.inc.h"
+#define BUILTIN_UNDERSCORED_ID array_iterator_prototype
+#include "ecma-builtin-internal-routines-template.inc.h"
+
+/** \addtogroup ecma ECMA
+ * @{
+ *
+ * \addtogroup ecmabuiltins
+ * @{
+ *
+ * \addtogroup %arrayiteratorprototype% ECMA %ArrayIteratorPrototype% object built-in
+ * @{
+ */
+
+/**
+ * The %ArrayIteratorPrototype% object's 'next' routine
+ *
+ * See also:
+ *          ECMA-262 v6, 22.1.5.2.1
+ *
+ * Note:
+ *     Returned value must be freed with ecma_free_value.
+ *
+ * @return iterator result object, if success
+ *         error - otherwise
+ */
+static ecma_value_t
+ecma_builtin_array_iterator_prototype_object_next (ecma_value_t this_val) /**< this argument */
+{
+  /* 1 - 2. */
+  if (!ecma_is_value_object (this_val))
+  {
+    return ecma_raise_type_error (ECMA_ERR_MSG ("Argument 'this' is not an object."));
+  }
+
+  ecma_object_t *obj_p = ecma_get_object_from_value (this_val);
+  ecma_extended_object_t *ext_obj_p = (ecma_extended_object_t *) obj_p;
+
+  /* 3. */
+  if (ext_obj_p->u.pseudo_array.type != ECMA_PSEUDO_ARRAY_ITERATOR)
+  {
+    return ecma_raise_type_error (ECMA_ERR_MSG ("Argument 'this' is not an iterator."));
+  }
+
+  ecma_object_t *array_object_p = ECMA_GET_POINTER (ecma_object_t,
+                                                    ext_obj_p->u.pseudo_array.u2.iterated_value_cp);
+
+
+  /* 4 - 5 */
+  if (array_object_p == NULL)
+  {
+    return ecma_create_iter_result_object (ECMA_VALUE_UNDEFINED, ECMA_VALUE_TRUE);
+  }
+
+  uint32_t length;
+
+  /* 8 - 9. */
+#ifndef CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN
+  if (ecma_is_typedarray (ecma_make_object_value (array_object_p)))
+  {
+    length = ecma_typedarray_get_length (array_object_p);
+  }
+  else
+  {
+#endif /* !CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN */
+    JERRY_ASSERT (ecma_get_object_type (array_object_p) == ECMA_OBJECT_TYPE_ARRAY);
+
+    ecma_extended_object_t *ext_array_obj_p = (ecma_extended_object_t *) array_object_p;
+
+    length = ext_array_obj_p->u.array.length;
+#ifndef CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN
+  }
+#endif /* !CONFIG_DISABLE_ES2015_TYPEDARRAY_BUILTIN */
+
+  uint32_t index = ext_obj_p->u.pseudo_array.u1.iterator_index;
+
+  if (JERRY_UNLIKELY (index == ECMA_ITERATOR_INDEX_LIMIT))
+  {
+    /* After the ECMA_ITERATOR_INDEX_LIMIT limit is reached the [[%Iterator%NextIndex]]
+       property is stored as an internal property */
+    ecma_string_t *prop_name_p = ecma_get_magic_string (LIT_INTERNAL_MAGIC_STRING_ITERATOR_NEXT_INDEX);
+    ecma_value_t index_value = ecma_op_object_get (obj_p, prop_name_p);
+
+    if (!ecma_is_value_undefined (index_value))
+    {
+      index = (uint32_t) (ecma_get_number_from_value (index_value) + 1);
+    }
+
+    ecma_value_t put_result = ecma_op_object_put (obj_p,
+                                                  prop_name_p,
+                                                  ecma_make_uint32_value (index),
+                                                  true);
+
+    JERRY_ASSERT (ecma_is_value_true (put_result));
+
+    ecma_free_value (index_value);
+  }
+  else
+  {
+    /* 11. */
+    ext_obj_p->u.pseudo_array.u1.iterator_index++;
+  }
+
+  if (index >= length)
+  {
+    ECMA_SET_POINTER (ext_obj_p->u.pseudo_array.u2.iterated_value_cp, NULL);
+    return ecma_create_iter_result_object (ECMA_VALUE_UNDEFINED, ECMA_VALUE_TRUE);
+  }
+
+  /* 7. */
+  uint8_t iterator_type = ext_obj_p->u.pseudo_array.extra_info;
+
+  if (iterator_type == ECMA_ARRAY_ITERATOR_KEYS)
+  {
+    /* 12. */
+    return ecma_create_iter_result_object (ecma_make_uint32_value (index), ECMA_VALUE_FALSE);
+  }
+
+  /* 13. */
+  ecma_string_t *index_string_p = ecma_new_ecma_string_from_uint32 (index);
+
+  /* 14. */
+  ecma_value_t get_value = ecma_op_object_get (array_object_p, index_string_p);
+  ecma_deref_ecma_string (index_string_p);
+
+  /* 15. */
+  if (ECMA_IS_VALUE_ERROR (get_value))
+  {
+    return get_value;
+  }
+
+  ecma_value_t result;
+
+  /* 16. */
+  if (iterator_type == ECMA_ARRAY_ITERATOR_VALUES)
+  {
+    result = ecma_create_iter_result_object (get_value, ECMA_VALUE_FALSE);
+  }
+  else
+  {
+    /* 17.a */
+    JERRY_ASSERT (iterator_type == ECMA_ARRAY_ITERATOR_KEYS_VALUES);
+
+    /* 17.b */
+    ecma_value_t entry_array_value;
+    entry_array_value = ecma_create_array_from_iter_element (get_value,
+                                                             ecma_make_uint32_value (index));
+
+    result = ecma_create_iter_result_object (entry_array_value, ECMA_VALUE_FALSE);
+    ecma_free_value (entry_array_value);
+  }
+
+  ecma_free_value (get_value);
+
+  return result;
+} /* ecma_builtin_array_iterator_prototype_object_next */
+
+/**
+ * @}
+ * @}
+ * @}
+ */
+
+#endif /* !CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN */

jerry-core/ecma/builtin-objects/ecma-builtin-array-iterator-prototype.inc.h

@@ -0,0 +1,34 @@
+/* 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.
+ */
+
+/*
+ * %ArrayIteratorPrototype% built-in description
+ */
+
+#include "ecma-builtin-helpers-macro-defines.inc.h"
+
+#ifndef CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN
+
+STRING_VALUE (LIT_GLOBAL_SYMBOL_TO_STRING_TAG,
+              LIT_MAGIC_STRING_ARRAY_ITERATOR_UL,
+              ECMA_PROPERTY_FLAG_CONFIGURABLE)
+
+/* Routine properties:
+ *  (property name, C routine name, arguments number or NON_FIXED, value of the routine's length property) */
+ROUTINE (LIT_MAGIC_STRING_NEXT, ecma_builtin_array_iterator_prototype_object_next, 0, 0)
+
+#endif /* !CONFIG_DISABLE_ES2015_ITERATOR_BUILTIN */
+
+#include "ecma-builtin-helpers-macro-undefs.inc.h"