Implement Array.prototype.splice().

JerryScript-DCO-1.0-Signed-off-by: Zsolt Borbély zsborbely.u-szeged@partner.samsung.com

jerry-core/ecma/builtin-objects/ecma-builtin-array-prototype.cpp

@@ -1435,6 +1435,311 @@ ecma_builtin_array_prototype_object_slice (ecma_value_t this_arg, /**< 'this' ar
   return ret_value;
 } /* ecma_builtin_array_prototype_object_slice */
 
+/**
+ * The Array.prototype object's 'splice' routine
+ *
+ * See also:
+ *          ECMA-262 v5, 15.4.4.12
+ *
+ * @return completion value
+ *         Returned value must be freed with ecma_free_completion_value.
+ */
+static ecma_completion_value_t
+ecma_builtin_array_prototype_object_splice (ecma_value_t this_arg, /**< this argument */
+                                          const ecma_value_t args[], /**< arguments list */
+                                          ecma_length_t args_number) /**< number of arguments */
+{
+  ecma_completion_value_t ret_value = ecma_make_empty_completion_value ();
+
+  /* 1. */
+  ECMA_TRY_CATCH (obj_this,
+                  ecma_op_to_object (this_arg),
+                  ret_value);
+
+  ecma_object_t *obj_p = ecma_get_object_from_value (obj_this);
+
+  /* 3. */
+  ecma_string_t *length_magic_string_p = ecma_get_magic_string (ECMA_MAGIC_STRING_LENGTH);
+
+  ECMA_TRY_CATCH (len_value,
+                  ecma_op_object_get (obj_p, length_magic_string_p),
+                  ret_value);
+
+  /* 4. */
+  ECMA_OP_TO_NUMBER_TRY_CATCH (len_number,
+                               len_value,
+                               ret_value);
+
+  const uint32_t len = ecma_number_to_uint32 (len_number);
+
+  ecma_completion_value_t new_array = ecma_op_create_array_object (0, 0, false);
+  ecma_object_t *new_array_p = ecma_get_object_from_completion_value (new_array);
+
+  uint32_t start = 0;
+  uint32_t delete_count = 0;
+
+  if (args_number > 0)
+  {
+    /* 5. */
+    ECMA_OP_TO_NUMBER_TRY_CATCH (start_num,
+                                 args[0],
+                                 ret_value);
+
+    int32_t relative_start = ecma_number_to_int32 (start_num);
+
+    /* 6. */
+    if (relative_start < 0)
+    {
+      uint32_t start_abs = (uint32_t) - relative_start;
+      if (start_abs > len)
+      {
+        start = 0;
+      }
+      else
+      {
+        start = len - start_abs;
+      }
+    }
+    else
+    {
+      start = (uint32_t) relative_start;
+      if (start > len)
+      {
+        start = len;
+      }
+    }
+
+    /*
+     * If there is only one argument, that will be the start argument,
+     * and we must delete the additional elements.
+     */
+    if (args_number == 1)
+    {
+      delete_count = len - start;
+    }
+    else
+    {
+      /* 7. */
+      ECMA_OP_TO_NUMBER_TRY_CATCH (delete_num,
+                                   args[1],
+                                   ret_value);
+
+      int32_t delete_count_int = ecma_number_to_int32 (delete_num);
+
+      if (delete_count_int > 0)
+      {
+        delete_count = (uint32_t) delete_count_int;
+      }
+      else
+      {
+        delete_count = 0;
+      }
+
+      if (len - start < delete_count)
+      {
+        delete_count = len - start;
+      }
+
+      ECMA_OP_TO_NUMBER_FINALIZE (delete_num);
+    }
+
+    ECMA_OP_TO_NUMBER_FINALIZE (start_num);
+  }
+
+  /* 8-9. */
+  uint32_t k;
+
+  for (uint32_t del_item_idx, k = 0;
+       k < delete_count && ecma_is_completion_value_empty (ret_value);
+       k++)
+  {
+    /* 9.a */
+    del_item_idx = k + start;
+    ecma_string_t *idx_str_p = ecma_new_ecma_string_from_uint32 (del_item_idx);
+
+    /* 9.b */
+    if (ecma_op_object_get_property (obj_p, idx_str_p) != NULL)
+    {
+      /* 9.c.i */
+      ECMA_TRY_CATCH (get_value,
+                      ecma_op_object_get (obj_p, idx_str_p),
+                      ret_value);
+
+      ecma_string_t *idx_str_new_p = ecma_new_ecma_string_from_uint32 (k);
+
+      /* 9.c.ii
+       * Using [[Put]] is equivalent to using [[DefineOwnProperty]] as specified the standard,
+       * so we use [[Put]] instead for simplicity. No need for a try-catch block since it is called
+       * with is_throw = false.
+       */
+      ECMA_TRY_CATCH (put_value,
+                      ecma_op_object_put (new_array_p, idx_str_new_p, get_value, false),
+                      ret_value);
+
+      ECMA_FINALIZE (put_value);
+      ecma_deref_ecma_string (idx_str_new_p);
+      ECMA_FINALIZE (get_value);
+    }
+
+    ecma_deref_ecma_string (idx_str_p);
+  }
+
+  /* 11. */
+  ecma_length_t item_count;
+
+  if (args_number > 2)
+  {
+    item_count = (ecma_length_t) (args_number - 2);
+  }
+  else
+  {
+    item_count = 0;
+  }
+
+  const uint32_t new_len = len - delete_count + item_count;
+
+  if (item_count != delete_count)
+  {
+    uint32_t from, to;
+
+    /* 12. */
+    if (item_count < delete_count)
+    {
+      /* 12.b */
+      for (k = start; k < (len - delete_count) && ecma_is_completion_value_empty (ret_value); k++)
+      {
+        from = k + delete_count;
+        ecma_string_t *from_str_p = ecma_new_ecma_string_from_uint32 (from);
+
+        to = k + item_count;
+        ecma_string_t *to_str_p = ecma_new_ecma_string_from_uint32 (to);
+
+        /* 12.b.iii */
+        if (ecma_op_object_get_property (obj_p, from_str_p) != NULL)
+        {
+          /* 12.b.iv */
+          ECMA_TRY_CATCH (get_value,
+                          ecma_op_object_get (obj_p, from_str_p),
+                          ret_value);
+
+          ECMA_TRY_CATCH (put_value,
+                          ecma_op_object_put (obj_p, to_str_p, get_value, true),
+                          ret_value);
+
+          ECMA_FINALIZE (put_value);
+          ECMA_FINALIZE (get_value);
+        }
+        else
+        {
+          /* 12.b.v */
+          ECMA_TRY_CATCH (del_value,
+                          ecma_op_object_delete (obj_p, to_str_p, true),
+                          ret_value);
+
+          ECMA_FINALIZE (del_value);
+        }
+
+        ecma_deref_ecma_string (to_str_p);
+        ecma_deref_ecma_string (from_str_p);
+      }
+
+      /* 12.d */
+      for (k = len; k > new_len && ecma_is_completion_value_empty (ret_value); k--)
+      {
+        ecma_string_t *str_idx_p = ecma_new_ecma_string_from_uint32 (k - 1);
+        ECMA_TRY_CATCH (del_value,
+                        ecma_op_object_delete (obj_p, str_idx_p, true),
+                        ret_value);
+
+        ECMA_FINALIZE (del_value);
+        ecma_deref_ecma_string (str_idx_p);
+      }
+    }
+    /* 13. */
+    else if (item_count > delete_count)
+    {
+      /* 13.b */
+      for (k = len - delete_count; k > start  && ecma_is_completion_value_empty (ret_value); k--)
+      {
+        from = k + delete_count - 1;
+        ecma_string_t *from_str_p = ecma_new_ecma_string_from_uint32 (from);
+
+        to = k + item_count - 1;
+        ecma_string_t *to_str_p = ecma_new_ecma_string_from_uint32 (to);
+
+        /* 13.b.iii */
+        if (ecma_op_object_get_property (obj_p, from_str_p) != NULL)
+        {
+          /* 13.b.iv */
+          ECMA_TRY_CATCH (get_value,
+                          ecma_op_object_get (obj_p, from_str_p),
+                          ret_value);
+
+          ECMA_TRY_CATCH (put_value,
+                          ecma_op_object_put (obj_p, to_str_p, get_value, true),
+                          ret_value);
+
+          ECMA_FINALIZE (put_value);
+          ECMA_FINALIZE (get_value);
+        }
+        else
+        {
+          /* 13.b.v */
+          ECMA_TRY_CATCH (del_value,
+                          ecma_op_object_delete (obj_p, to_str_p, true),
+                          ret_value);
+
+          ECMA_FINALIZE (del_value);
+        }
+
+        ecma_deref_ecma_string (to_str_p);
+        ecma_deref_ecma_string (from_str_p);
+      }
+    }
+  }
+
+  /* 15. */
+  ecma_length_t idx = 0;
+  for (ecma_length_t arg_index = 2;
+       arg_index < args_number && ecma_is_completion_value_empty (ret_value);
+       arg_index++, idx++)
+  {
+    ecma_string_t *str_idx_p = ecma_new_ecma_string_from_uint32 ((uint32_t) (start + idx));
+    ECMA_TRY_CATCH (put_value,
+                    ecma_op_object_put (obj_p, str_idx_p, args[arg_index], true),
+                    ret_value);
+
+    ECMA_FINALIZE (put_value);
+    ecma_deref_ecma_string (str_idx_p);
+  }
+
+  /* 16. */
+  if (ecma_is_completion_value_empty (ret_value))
+  {
+    ECMA_TRY_CATCH (set_length_value,
+                    ecma_builtin_array_prototype_helper_set_length (obj_p, new_len),
+                    ret_value);
+
+    ECMA_FINALIZE (set_length_value);
+  }
+
+  if (ecma_is_completion_value_empty (ret_value))
+  {
+    ret_value = new_array;
+  }
+  else
+  {
+    ecma_free_completion_value (new_array);
+  }
+
+  ECMA_OP_TO_NUMBER_FINALIZE (len_number);
+  ECMA_FINALIZE (len_value);
+  ecma_deref_ecma_string (length_magic_string_p);
+  ECMA_FINALIZE (obj_this);
+
+  return ret_value;
+} /* ecma_builtin_array_prototype_object_splice */
+
 /**
  * @}
  * @}

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

@@ -71,6 +71,7 @@ ROUTINE (ECMA_MAGIC_STRING_UNSHIFT, ecma_builtin_array_prototype_object_unshift,
 ROUTINE (ECMA_MAGIC_STRING_EVERY, ecma_builtin_array_prototype_object_every, 2, 1)
 ROUTINE (ECMA_MAGIC_STRING_SOME, ecma_builtin_array_prototype_object_some, 2, 1)
 ROUTINE (ECMA_MAGIC_STRING_SLICE, ecma_builtin_array_prototype_object_slice, 2, 2)
+ROUTINE (ECMA_MAGIC_STRING_SPLICE, ecma_builtin_array_prototype_object_splice, NON_FIXED, 2)
 
 #undef OBJECT_ID
 #undef SIMPLE_VALUE

tests/jerry/array_prototype_splice.js

@@ -0,0 +1,113 @@
+// Copyright 2015 Samsung Electronics Co., Ltd.
+// Copyright 2015 University of Szeged.
+//
+// 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.
+
+function setDefaultValues()
+{
+	return [54, undefined, -127, "sunshine"];
+}
+
+var array = setDefaultValues();
+var array1 = array.splice();
+
+assert (array.length == 4);
+assert (array[0] == 54);
+assert (array[1] == undefined);
+assert (array[2] == -127);
+assert (array[3] == "sunshine");
+assert (array1.length == 0);
+
+// --------------------------------------------------------
+array = setDefaultValues();
+var array2 = array.splice(2);
+
+assert (array.length == 2);
+assert (array[0] == 54);
+assert (array[1] == undefined);
+assert (array2.length == 2);
+assert (array2[0] == -127);
+assert (array2[1] == "sunshine");
+
+// --------------------------------------------------------
+array = setDefaultValues();
+var array3 = array.splice(2, 1);
+
+assert (array.length == 3);
+assert (array[0] == 54);
+assert (array[1] == undefined);
+assert (array[2] == "sunshine");
+assert (array3.length == 1);
+assert (array3[0] == -127);
+
+// --------------------------------------------------------
+array = setDefaultValues();
+var array4 = array.splice(0, 3, 6720, "Szeged");
+
+assert (array.length == 3);
+assert (array[0] == 6720);
+assert (array[1] == "Szeged");
+assert (array[2] == "sunshine");
+assert (array4.length == 3);
+assert (array4[0] == 54);
+assert (array4[1] == undefined);
+assert (array4[2] == -127);
+
+// --------------------------------------------------------
+array = setDefaultValues();
+var array5 = array.splice(-2, -2, 6720, "Szeged");
+
+assert (array.length == 6);
+assert (array[0] == 54);
+assert (array[1] == undefined);
+assert (array[2] == 6720);
+assert (array[3] == "Szeged");
+assert (array[4] == -127);
+assert (array[5] == "sunshine");
+assert (array5.length == 0);
+
+// --------------------------------------------------------
+array = setDefaultValues();
+var array6 = array.splice(undefined, undefined, undefined);
+
+assert (array.length == 5);
+assert (array[0] == undefined);
+assert (array[1] == 54);
+assert (array[2] == undefined);
+assert (array[3] == -127);
+assert (array[4] == "sunshine");
+assert (array6.length == 0);
+
+// Checking behavior when unable to get length
+var obj = {splice : Array.prototype.splice};
+Object.defineProperty(obj, 'length', { 'get' : function () { throw new ReferenceError ("foo"); } });
+
+try {
+	obj.splice(1, 2, "item1", "item2");
+	assert (false);
+} catch (e) {
+	assert (e.message === "foo");
+	assert (e instanceof ReferenceError);
+}
+
+// Checking behavior when unable to get element
+var obj = {length : 1, splice : Array.prototype.splice};
+Object.defineProperty(obj, '0', { 'get' : function () { throw new ReferenceError ("foo"); } });
+
+try {
+	obj.splice(0, 1, "item1", "item2");
+	assert (false);
+} catch (e) {
+	assert (e.message === "foo");
+	assert (e instanceof ReferenceError);
+}