Implement Number.prototype.toPrecision()

JerryScript-DCO-1.0-Signed-off-by: Dániel Bátyai dbatyai.u-szeged@partner.samsung.com
This commit is contained in:
Dániel Bátyai
2015-07-01 11:15:18 +02:00
parent 53cbb55f25
commit 713b433c42
2 changed files with 271 additions and 1 deletions
@@ -579,7 +579,223 @@ static ecma_completion_value_t
ecma_builtin_number_prototype_object_to_precision (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_OP_TO_NUMBER_TRY_CATCH (this_num, this_arg, ret_value);
/* 2. */
if (ecma_is_value_undefined (arg))
{
ret_value = ecma_builtin_number_prototype_object_to_string (this_arg, NULL, 0);
}
else
{
/* 3. */
ECMA_OP_TO_NUMBER_TRY_CATCH (arg_num, arg, ret_value);
/* 4. */
if (ecma_number_is_nan (this_num))
{
ecma_string_t *nan_str_p = ecma_get_magic_string (LIT_MAGIC_STRING_NAN);
ret_value = ecma_make_normal_completion_value (ecma_make_string_value (nan_str_p));
}
else
{
bool is_negative = false;
/* 6. */
if (ecma_number_is_negative (this_num) && !ecma_number_is_zero (this_num))
{
is_negative = true;
this_num *= -1;
}
/* 7. */
if (ecma_number_is_infinity (this_num))
{
ecma_string_t *infinity_str_p = ecma_get_magic_string (LIT_MAGIC_STRING_INFINITY_UL);
if (is_negative)
{
ecma_string_t *neg_str_p = ecma_get_magic_string (LIT_MAGIC_STRING_MINUS_CHAR);
ecma_string_t *neg_inf_str_p = ecma_concat_ecma_strings (neg_str_p, infinity_str_p);
ecma_deref_ecma_string (infinity_str_p);
ecma_deref_ecma_string (neg_str_p);
ret_value = ecma_make_normal_completion_value (ecma_make_string_value (neg_inf_str_p));
}
else
{
ret_value = ecma_make_normal_completion_value (ecma_make_string_value (infinity_str_p));
}
}
/* 8. */
else if (arg_num < 1.0 || arg_num >= 22.0)
{
ret_value = ecma_make_throw_obj_completion_value (ecma_new_standard_error (ECMA_ERROR_RANGE));
}
else
{
uint64_t digits = 0;
int32_t num_digits = 0;
int32_t exponent = 1;
int32_t precision = ecma_number_to_int32 (arg_num);
/* Get the parameters of the number if non-zero. */
if (!ecma_number_is_zero (this_num))
{
ecma_number_to_decimal (this_num, &digits, &num_digits, &exponent);
}
digits = ecma_builtin_number_prototype_helper_round (digits, num_digits - precision);
int buffer_size;
if (exponent < -5 || exponent > precision)
{
/* Exponential notation, precision + 1 digits for number, 5 for exponent, 1 for \0 */
buffer_size = precision + 1 + 5 + 1;
}
else if (exponent <= 0)
{
/* Fixed notation, -exponent + 2 digits for leading zeros, precision digits, 1 for \0 */
buffer_size = -exponent + 2 + precision + 1;
}
else
{
/* Fixed notation, precision + 1 digits for number, 1 for \0 */
buffer_size = precision + 1 + 1;
}
if (is_negative)
{
buffer_size++;
}
MEM_DEFINE_LOCAL_ARRAY (buff, buffer_size, lit_utf8_byte_t);
lit_utf8_byte_t *actual_char_p = buff;
uint64_t scale = 1;
/* Calculate the magnitude of the number. This is used to get the digits from left to right. */
while (scale <= digits)
{
scale *= 10;
}
if (is_negative)
{
*actual_char_p++ = '-';
}
int digit = 0;
/* 10.c, Exponential notation.*/
if (exponent < -5 || exponent > precision)
{
/* Add significant digits. */
for (int i = 1; i <= precision; i++)
{
digit = 0;
scale /= 10;
while (digits >= scale && scale > 0)
{
digits -= scale;
digit++;
}
*actual_char_p++ = (lit_utf8_byte_t) (digit + '0');
if (i == 1 && i != precision)
{
*actual_char_p++ = '.';
}
}
*actual_char_p++ = 'e';
exponent--;
if (exponent < 0)
{
exponent *= -1;
*actual_char_p++ = '-';
}
else
{
*actual_char_p++ = '+';
}
/* Get magnitude of exponent. */
int32_t scale_expt = 1;
while (scale_expt <= exponent)
{
scale_expt *= 10;
}
scale_expt /= 10;
/* Add exponent digits. */
if (exponent == 0)
{
*actual_char_p++ = '0';
}
else
{
while (scale_expt > 0)
{
digit = exponent / scale_expt;
exponent %= scale_expt;
*actual_char_p++ = (lit_utf8_byte_t) (digit + '0');
scale_expt /= 10;
}
}
}
/* Fixed notation. */
else
{
/* Add leading zeros if neccessary. */
if (exponent <= 0)
{
*actual_char_p++ = '0';
*actual_char_p++ = '.';
for (int i = exponent; i < 0; i++)
{
*actual_char_p++ = '0';
}
}
/* Add significant digits. */
for (int i = 1; i <= precision; i++)
{
digit = 0;
scale /= 10;
while (digits >= scale && scale > 0)
{
digits -= scale;
digit++;
}
*actual_char_p++ = (lit_utf8_byte_t) (digit + '0');
if (i == exponent && i != precision)
{
*actual_char_p++ = '.';
}
}
}
JERRY_ASSERT (actual_char_p - buff < buffer_size);
*actual_char_p = '\0';
ecma_string_t *str_p = ecma_new_ecma_string_from_utf8 (buff, (lit_utf8_size_t) (actual_char_p - buff));
ret_value = ecma_make_normal_completion_value (ecma_make_string_value (str_p));
MEM_FINALIZE_LOCAL_ARRAY (buff);
}
}
ECMA_OP_TO_NUMBER_FINALIZE (arg_num);
}
ECMA_OP_TO_NUMBER_FINALIZE (this_num);
return ret_value;
} /* ecma_builtin_number_prototype_object_to_precision */
/**
@@ -0,0 +1,54 @@
// 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.
//This test will not pass on FLOAT32 due to precision issues
assert((123.56).toPrecision() === "123.56");
assert((123.56).toPrecision(1) === "1e+2");
assert((123.56).toPrecision(2) === "1.2e+2");
assert((123.56).toPrecision(6) === "123.560");
assert((-1.23).toPrecision(1) === "-1");
assert((0.00023).toPrecision(1) === "0.0002");
assert((0.356).toPrecision(2) === "0.36");
assert((0.0000356).toPrecision(5) === "0.000035600");
assert((0.000030056).toPrecision(4) === "0.00003006");
assert(Infinity.toPrecision(1) === "Infinity");
assert((-Infinity).toPrecision(1) === "-Infinity");
assert(NaN.toPrecision(1) === "NaN");
assert((0.0).toPrecision(1) === "0");
assert((-0.0).toPrecision(1) === "0");
assert((0.0).toPrecision(6) === "0.00000");
assert((123456789012345678901.0).toPrecision(20) === "1.2345678901234568000e+20");
assert((123456789012345678901.0).toPrecision(21) === "123456789012345680000");
assert((123456789012345678901.0).toPrecision("6") === "1.23457e+20");
var obj = { toPrecision : Number.prototype.toPrecision };
assert(obj.toPrecision(1) === "NaN");
assert((123.56).toPrecision(1.3) === "1e+2");
assert((123.56).toPrecision(21.9) === "123.560000000000000000");
try {
(12).toPrecision(0);
assert(false);
} catch (e) {
assert(e instanceof RangeError)
}
try {
(12).toPrecision(22);
assert(false);
} catch (e) {
assert(e instanceof RangeError)
}