Array.prototype.reduce()

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

@@ -1237,6 +1237,147 @@ 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 'reduce' routine
+ *
+ * See also:
+ *          ECMA-262 v5, 15.4.4.21
+ *
+ * @return completion value
+ *         Returned value must be freed with ecma_free_completion_value.
+ */
+static ecma_completion_value_t
+ecma_builtin_array_prototype_object_reduce (ecma_value_t this_arg, /**< this argument */
+                                            ecma_value_t arg1, /**< callbackfn */
+                                            ecma_value_t arg2) /**< initialValue */
+{
+  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);
+  ecma_string_t *magic_string_length_p = ecma_get_magic_string (ECMA_MAGIC_STRING_LENGTH);
+
+  /* 2 */
+  ECMA_TRY_CATCH (len_value,
+                  ecma_op_object_get (obj_p, magic_string_length_p),
+                  ret_value);
+
+  ECMA_OP_TO_NUMBER_TRY_CATCH (len_number, len_value, ret_value);
+
+  /* 3 */
+  uint32_t len = ecma_number_to_uint32 (len_number);
+
+  /* 4 */
+  if (!ecma_op_is_callable (arg1))
+  {
+    ret_value = ecma_make_throw_obj_completion_value (ecma_new_standard_error (ECMA_ERROR_TYPE));
+  }
+  else
+  {
+    ecma_completion_value_t accumulator = ecma_make_empty_completion_value ();
+    ecma_number_t *num_p = ecma_alloc_number ();
+    ecma_object_t *func_object_p;
+    ecma_value_t current_index;
+
+    ecma_completion_value_t to_object_comp = ecma_op_to_object (arg1);
+    JERRY_ASSERT (ecma_is_completion_value_normal (to_object_comp));
+    func_object_p = ecma_get_object_from_completion_value (to_object_comp);
+
+    /* 5 */
+    if (len_number == ECMA_NUMBER_ZERO && ecma_is_value_undefined (arg1))
+    {
+      ret_value = ecma_make_throw_obj_completion_value (ecma_new_standard_error (ECMA_ERROR_TYPE));
+    }
+
+    /* 6 */
+    uint32_t index = 0;
+
+    /* 7a */
+    if (!ecma_is_value_undefined (arg2))
+    {
+      accumulator = ecma_copy_completion_value (arg2);
+    }
+    else
+    {
+      /* 8a */
+      bool kPresent = false;
+      /* 8b */
+      while (!kPresent && index < len && ecma_is_completion_value_empty (ret_value))
+      {
+        /* 8b-i */
+        ecma_string_t *index_str_p = ecma_new_ecma_string_from_uint32 (index);
+
+        /* 8b-ii-iii */
+        if ((kPresent = (ecma_op_object_get_property (obj_p, index_str_p) != NULL)))
+        {
+          ECMA_TRY_CATCH (current_value, ecma_op_object_get (obj_p, index_str_p), ret_value);
+          accumulator = ecma_copy_completion_value (current_value);
+          ECMA_FINALIZE (current_value);
+        }
+        /* 8b-iv */
+        index++;
+
+        ecma_deref_ecma_string (index_str_p);
+      }
+      /* 8c */
+      if (!kPresent)
+      {
+        ret_value = ecma_make_throw_obj_completion_value (ecma_new_standard_error (ECMA_ERROR_TYPE));
+      }
+    }
+    /* 9 */
+    for (; index < len && ecma_is_completion_value_empty (ret_value); ++index)
+    {
+      /* 9a */
+      ecma_string_t *index_str_p = ecma_new_ecma_string_from_uint32 (index);
+      /* 9b */
+      if (ecma_op_object_get_property (obj_p, index_str_p) != NULL)
+      {
+        /* 9c-i */
+        ECMA_TRY_CATCH (current_value, ecma_op_object_get (obj_p, index_str_p), ret_value);
+        /* 9c-ii */
+        *num_p = ecma_uint32_to_number (index);
+        current_index = ecma_make_number_value (num_p);
+        ecma_value_t prev_value = ecma_get_completion_value_value (accumulator);
+        ecma_value_t call_args[] = {prev_value, current_value, current_index, obj_this};
+        ecma_value_t undefined_value = ecma_make_simple_value (ECMA_SIMPLE_VALUE_UNDEFINED);
+
+        ECMA_TRY_CATCH (call_value,
+                        ecma_op_function_call (func_object_p, undefined_value, call_args, 4),
+                        ret_value);
+
+        ecma_free_completion_value (accumulator);
+        accumulator = ecma_copy_completion_value (call_value);
+
+        ECMA_FINALIZE (call_value);
+        ecma_free_value (undefined_value, false);
+        ECMA_FINALIZE (current_value);
+      }
+      ecma_deref_ecma_string (index_str_p);
+      /* 9d in for loop */
+    }
+
+    if (ecma_is_completion_value_empty (ret_value))
+    {
+      ret_value = ecma_copy_completion_value (accumulator);
+    }
+    ecma_free_completion_value (accumulator);
+    ecma_free_completion_value (to_object_comp);
+    ecma_dealloc_number (num_p);
+  }
+
+  ECMA_OP_TO_NUMBER_FINALIZE (len_number);
+  ECMA_FINALIZE (len_value);
+  ecma_deref_ecma_string (magic_string_length_p);
+  ECMA_FINALIZE (obj_this);
+
+  return ret_value;
+} /* ecma_builtin_array_prototype_object_reduce */
+
 /**
  * @}
  * @}

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

@@ -69,6 +69,7 @@ ROUTINE (ECMA_MAGIC_STRING_SHIFT, ecma_builtin_array_prototype_object_shift, 0,
 ROUTINE (ECMA_MAGIC_STRING_UNSHIFT, ecma_builtin_array_prototype_object_unshift, NON_FIXED, 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_REDUCE, ecma_builtin_array_prototype_object_reduce, 2, 1)
 
 #undef OBJECT_ID
 #undef SIMPLE_VALUE

tests/jerry/array_prototype_reduce.js

@@ -0,0 +1,55 @@
+// 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.
+
+var func = function(a, b) {
+  return a + b;
+}
+
+// check function type
+try {
+  [0].reduce(new Object());
+  assert(false);
+} catch(e) {
+  assert(e instanceof TypeError);
+}
+
+// check for init value
+try {
+  [].reduce(func);
+}
+catch(e) {
+  assert(e instanceof TypeError);
+}
+
+// various checks
+assert ([].reduce(func, 1) === 1);
+
+assert ([0].reduce(func) === 0);
+
+assert ([0, 1].reduce(func) === 1);
+
+assert ([0, 1].reduce(func, 1) === 2);
+
+assert ([0, 1, 2, 3].reduce(func, 1) === 7);
+
+assert (["A","B"].reduce(func) === "AB");
+
+assert (["A","B"].reduce(func, "Init:") === "Init:AB");
+
+assert ([0, 1].reduce(func, 3.2) === 4.2);
+
+assert ([0, "x", 1].reduce(func) === "0x1");
+
+assert ([0, "x", 1].reduce(func, 3.2) === "3.2x1");