Implement String.prototype.charCodeAt()

JerryScript-DCO-1.0-Signed-off-by: Laszlo Vidacs [email protected]

Author: lvidacs

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

@@ -169,7 +169,59 @@ static ecma_completion_value_t
 ecma_builtin_string_prototype_object_char_code_at (ecma_value_t this_arg, /**< this argument */
                                                    ecma_value_t arg) /**< routine's argument */
 {
-  ECMA_BUILTIN_CP_UNIMPLEMENTED (this_arg, arg);
+  ecma_completion_value_t ret_value = ecma_make_empty_completion_value ();
+
+  /* 1 */
+  ECMA_TRY_CATCH (check_coercible_val,
+                  ecma_op_check_object_coercible (this_arg),
+                  ret_value);
+
+  /* 2 */
+  ECMA_TRY_CATCH (to_string_val,
+                  ecma_op_to_string (this_arg),
+                  ret_value);
+
+  /* 3 */
+  ECMA_OP_TO_NUMBER_TRY_CATCH (index_num,
+                               arg,
+                               ret_value);
+
+  /* 4 */
+  ecma_string_t *original_string_p = ecma_get_string_from_value (to_string_val);
+  const ecma_length_t len = ecma_string_get_length (original_string_p);
+
+  ecma_number_t *ret_num_p = ecma_alloc_number ();
+
+  /* 5 */
+  // When index_num is NaN, then the first two comparisons are false
+  if (index_num < 0 || index_num >= len || (ecma_number_is_nan (index_num) && !len))
+  {
+    *ret_num_p = ecma_number_make_nan ();
+  }
+  else
+  {
+    /* 6 */
+    /*
+     * String length is currently uit32_t, but index_num may be bigger,
+     * ToInteger performs floor, while ToUInt32 performs modulo 2^32,
+     * hence after the check 0 <= index_num < len we assume to_uint32 can be used.
+     * We assume to_uint32 (NaN) is 0.
+     */
+    JERRY_ASSERT (ecma_number_is_nan (index_num) || ecma_number_to_uint32 (index_num) == ecma_number_trunc (index_num));
+
+    ecma_char_t new_ecma_char = ecma_string_get_char_at_pos (original_string_p, ecma_number_to_uint32 (index_num));
+    *ret_num_p = ecma_uint32_to_number (new_ecma_char);
+  }
+
+  ecma_value_t new_value = ecma_make_number_value (ret_num_p);
+  ret_value = ecma_make_normal_completion_value (new_value);
+
+  ECMA_OP_TO_NUMBER_FINALIZE (index_num);
+
+  ECMA_FINALIZE (to_string_val);
+  ECMA_FINALIZE (check_coercible_val);
+
+  return ret_value;
 } /* ecma_builtin_string_prototype_object_char_code_at */
 
 /**

tests/jerry/string-prototype-charcodeat.js

@@ -0,0 +1,90 @@
+// 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.
+
+// check properties
+assert(Object.getOwnPropertyDescriptor(String.prototype.charCodeAt, 'length').configurable === false);
+
+assert(Object.getOwnPropertyDescriptor(String.prototype.charCodeAt, 'length').enumerable === false);
+
+assert(Object.getOwnPropertyDescriptor(String.prototype.charCodeAt, 'length').writable === false);
+
+assert(String.prototype.charCodeAt.length === 1);
+
+// check empty string
+assert(isNaN(String.prototype.charCodeAt.call(new String())));
+
+// check Object with NaN pos
+assert(String.prototype.charCodeAt.call({}) === 91);
+
+// simple checks
+assert("hello world!".charCodeAt(0) === 104);
+
+assert("hello world!".charCodeAt(1) === 101);
+
+assert("HELLO WORLD".charCodeAt(10) === 68);
+
+// check +-Inf
+assert(isNaN("hello world!".charCodeAt(-Infinity)));
+
+assert(isNaN("hello world!".charCodeAt(Infinity)));
+
+assert("hello world!".charCodeAt(11) === 33);
+
+assert(isNaN("hello world!".charCodeAt(12)));
+
+// check negative
+assert(isNaN("hello world!".charCodeAt(-1)));
+
+assert(isNaN("hello world!".charCodeAt(-9999999)));
+
+assert("hello world!".charCodeAt(-0) === 104);
+
+// check undefined
+assert("hello world!".charCodeAt(undefined) === 104);
+
+// check booleans
+assert("hello world!".charCodeAt(true) === 101);
+
+assert("hello world!".charCodeAt(false) === 104);
+
+// check index above uint32_t
+assert(isNaN("hello world!".charCodeAt(4294967299)));
+
+// check coercible - undefined
+try {
+  assert(isNaN(String.prototype.charCodeAt.call(undefined)));
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+// check coercible - null
+try {
+  assert(isNaN(String.prototype.charCodeAt.call(null, 0)));
+  assert(false);
+} catch (e) {
+  assert(e instanceof TypeError);
+}
+
+// check coercible - Boolean
+assert(String.prototype.charCodeAt.call(true, 1) === 114);
+assert(String.prototype.charCodeAt.call(true) === 116);
+
+// check coercible - Object
+var test_object = {firstName:"John", lastName:"Doe"};
+assert(String.prototype.charCodeAt.call(test_object, 1) === 111);
+
+// check coercible - Number
+assert(String.prototype.charCodeAt.call(123, 2) === 51);