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<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Yaml;
use Symfony\Component\Yaml\Exception\ParseException;
use Symfony\Component\Yaml\Exception\DumpException;
use Symfony\Component\Yaml\Tag\TaggedValue;
/**
* Inline implements a YAML parser/dumper for the YAML inline syntax.
*
* @author Fabien Potencier <fabien@symfony.com>
*
* @internal
*/
class Inline
{
const REGEX_QUOTED_STRING = '(?:"([^"\\\\]*+(?:\\\\.[^"\\\\]*+)*+)"|\'([^\']*+(?:\'\'[^\']*+)*+)\')';
public static $parsedLineNumber;
private static $exceptionOnInvalidType = false;
private static $objectSupport = false;
private static $objectForMap = false;
private static $constantSupport = false;
/**
* Converts a YAML string to a PHP value.
*
* @param string $value A YAML string
* @param int $flags A bit field of PARSE_* constants to customize the YAML parser behavior
* @param array $references Mapping of variable names to values
*
* @return mixed A PHP value
*
* @throws ParseException
*/
public static function parse($value, $flags = 0, $references = array())
{
if (is_bool($flags)) {
@trigger_error('Passing a boolean flag to toggle exception handling is deprecated since version 3.1 and will be removed in 4.0. Use the Yaml::PARSE_EXCEPTION_ON_INVALID_TYPE flag instead.', E_USER_DEPRECATED);
if ($flags) {
$flags = Yaml::PARSE_EXCEPTION_ON_INVALID_TYPE;
} else {
$flags = 0;
}
}
if (func_num_args() >= 3 && !is_array($references)) {
@trigger_error('Passing a boolean flag to toggle object support is deprecated since version 3.1 and will be removed in 4.0. Use the Yaml::PARSE_OBJECT flag instead.', E_USER_DEPRECATED);
if ($references) {
$flags |= Yaml::PARSE_OBJECT;
}
if (func_num_args() >= 4) {
@trigger_error('Passing a boolean flag to toggle object for map support is deprecated since version 3.1 and will be removed in 4.0. Use the Yaml::PARSE_OBJECT_FOR_MAP flag instead.', E_USER_DEPRECATED);
if (func_get_arg(3)) {
$flags |= Yaml::PARSE_OBJECT_FOR_MAP;
}
}
if (func_num_args() >= 5) {
$references = func_get_arg(4);
} else {
$references = array();
}
}
self::$exceptionOnInvalidType = (bool) (Yaml::PARSE_EXCEPTION_ON_INVALID_TYPE & $flags);
self::$objectSupport = (bool) (Yaml::PARSE_OBJECT & $flags);
self::$objectForMap = (bool) (Yaml::PARSE_OBJECT_FOR_MAP & $flags);
self::$constantSupport = (bool) (Yaml::PARSE_CONSTANT & $flags);
$value = trim($value);
if ('' === $value) {
return '';
}
if (2 /* MB_OVERLOAD_STRING */ & (int) ini_get('mbstring.func_overload')) {
$mbEncoding = mb_internal_encoding();
mb_internal_encoding('ASCII');
}
$i = 0;
$tag = self::parseTag($value, $i, $flags);
switch ($value[$i]) {
case '[':
$result = self::parseSequence($value, $flags, $i, $references);
++$i;
break;
case '{':
$result = self::parseMapping($value, $flags, $i, $references);
++$i;
break;
default:
$result = self::parseScalar($value, $flags, null, $i, null === $tag, $references);
}
if (null !== $tag) {
return new TaggedValue($tag, $result);
}
// some comments are allowed at the end
if (preg_replace('/\s+#.*$/A', '', substr($value, $i))) {
throw new ParseException(sprintf('Unexpected characters near "%s".', substr($value, $i)));
}
if (isset($mbEncoding)) {
mb_internal_encoding($mbEncoding);
}
return $result;
}
/**
* Dumps a given PHP variable to a YAML string.
*
* @param mixed $value The PHP variable to convert
* @param int $flags A bit field of Yaml::DUMP_* constants to customize the dumped YAML string
*
* @return string The YAML string representing the PHP value
*
* @throws DumpException When trying to dump PHP resource
*/
public static function dump($value, $flags = 0)
{
if (is_bool($flags)) {
@trigger_error('Passing a boolean flag to toggle exception handling is deprecated since version 3.1 and will be removed in 4.0. Use the Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE flag instead.', E_USER_DEPRECATED);
if ($flags) {
$flags = Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE;
} else {
$flags = 0;
}
}
if (func_num_args() >= 3) {
@trigger_error('Passing a boolean flag to toggle object support is deprecated since version 3.1 and will be removed in 4.0. Use the Yaml::DUMP_OBJECT flag instead.', E_USER_DEPRECATED);
if (func_get_arg(2)) {
$flags |= Yaml::DUMP_OBJECT;
}
}
switch (true) {
case is_resource($value):
if (Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE & $flags) {
throw new DumpException(sprintf('Unable to dump PHP resources in a YAML file ("%s").', get_resource_type($value)));
}
return 'null';
case $value instanceof \DateTimeInterface:
return $value->format('c');
case is_object($value):
if ($value instanceof TaggedValue) {
return '!'.$value->getTag().' '.self::dump($value->getValue(), $flags);
}
if (Yaml::DUMP_OBJECT & $flags) {
return '!php/object:'.serialize($value);
}
if (Yaml::DUMP_OBJECT_AS_MAP & $flags && ($value instanceof \stdClass || $value instanceof \ArrayObject)) {
return self::dumpArray($value, $flags & ~Yaml::DUMP_EMPTY_ARRAY_AS_SEQUENCE);
}
if (Yaml::DUMP_EXCEPTION_ON_INVALID_TYPE & $flags) {
throw new DumpException('Object support when dumping a YAML file has been disabled.');
}
return 'null';
case is_array($value):
return self::dumpArray($value, $flags);
case null === $value:
return 'null';
case true === $value:
return 'true';
case false === $value:
return 'false';
case ctype_digit($value):
return is_string($value) ? "'$value'" : (int) $value;
case is_numeric($value):
$locale = setlocale(LC_NUMERIC, 0);
if (false !== $locale) {
setlocale(LC_NUMERIC, 'C');
}
if (is_float($value)) {
$repr = (string) $value;
if (is_infinite($value)) {
$repr = str_ireplace('INF', '.Inf', $repr);
} elseif (floor($value) == $value && $repr == $value) {
// Preserve float data type since storing a whole number will result in integer value.
$repr = '!!float '.$repr;
}
} else {
$repr = is_string($value) ? "'$value'" : (string) $value;
}
if (false !== $locale) {
setlocale(LC_NUMERIC, $locale);
}
return $repr;
case '' == $value:
return "''";
case self::isBinaryString($value):
return '!!binary '.base64_encode($value);
case Escaper::requiresDoubleQuoting($value):
return Escaper::escapeWithDoubleQuotes($value);
case Escaper::requiresSingleQuoting($value):
case Parser::preg_match('{^[0-9]+[_0-9]*$}', $value):
case Parser::preg_match(self::getHexRegex(), $value):
case Parser::preg_match(self::getTimestampRegex(), $value):
return Escaper::escapeWithSingleQuotes($value);
default:
return $value;
}
}
/**
* Check if given array is hash or just normal indexed array.
*
* @internal
*
* @param array|\ArrayObject|\stdClass $value The PHP array or array-like object to check
*
* @return bool true if value is hash array, false otherwise
*/
public static function isHash($value)
{
if ($value instanceof \stdClass || $value instanceof \ArrayObject) {
return true;
}
$expectedKey = 0;
foreach ($value as $key => $val) {
if ($key !== $expectedKey++) {
return true;
}
}
return false;
}
/**
* Dumps a PHP array to a YAML string.
*
* @param array $value The PHP array to dump
* @param int $flags A bit field of Yaml::DUMP_* constants to customize the dumped YAML string
*
* @return string The YAML string representing the PHP array
*/
private static function dumpArray($value, $flags)
{
// array
if (($value || Yaml::DUMP_EMPTY_ARRAY_AS_SEQUENCE & $flags) && !self::isHash($value)) {
$output = array();
foreach ($value as $val) {
$output[] = self::dump($val, $flags);
}
return sprintf('[%s]', implode(', ', $output));
}
// hash
$output = array();
foreach ($value as $key => $val) {
$output[] = sprintf('%s: %s', self::dump($key, $flags), self::dump($val, $flags));
}
return sprintf('{ %s }', implode(', ', $output));
}
/**
* Parses a YAML scalar.
*
* @param string $scalar
* @param int $flags
* @param string[] $delimiters
* @param int &$i
* @param bool $evaluate
* @param array $references
*
* @return string
*
* @throws ParseException When malformed inline YAML string is parsed
*
* @internal
*/
public static function parseScalar($scalar, $flags = 0, $delimiters = null, &$i = 0, $evaluate = true, $references = array(), $legacyOmittedKeySupport = false)
{
if (in_array($scalar[$i], array('"', "'"))) {
// quoted scalar
$output = self::parseQuotedScalar($scalar, $i);
if (null !== $delimiters) {
$tmp = ltrim(substr($scalar, $i), ' ');
if (!in_array($tmp[0], $delimiters)) {
throw new ParseException(sprintf('Unexpected characters (%s).', substr($scalar, $i)));
}
}
} else {
// "normal" string
if (!$delimiters) {
$output = substr($scalar, $i);
$i += strlen($output);
// remove comments
if (Parser::preg_match('/[ \t]+#/', $output, $match, PREG_OFFSET_CAPTURE)) {
$output = substr($output, 0, $match[0][1]);
}
} elseif (Parser::preg_match('/^(.'.($legacyOmittedKeySupport ? '+' : '*').'?)('.implode('|', $delimiters).')/', substr($scalar, $i), $match)) {
$output = $match[1];
$i += strlen($output);
} else {
throw new ParseException(sprintf('Malformed inline YAML string: %s.', $scalar));
}
// a non-quoted string cannot start with @ or ` (reserved) nor with a scalar indicator (| or >)
if ($output && ('@' === $output[0] || '`' === $output[0] || '|' === $output[0] || '>' === $output[0])) {
throw new ParseException(sprintf('The reserved indicator "%s" cannot start a plain scalar; you need to quote the scalar.', $output[0]));
}
if ($output && '%' === $output[0]) {
@trigger_error(sprintf('Not quoting the scalar "%s" starting with the "%%" indicator character is deprecated since Symfony 3.1 and will throw a ParseException in 4.0.', $output), E_USER_DEPRECATED);
}
if ($evaluate) {
$output = self::evaluateScalar($output, $flags, $references);
}
}
return $output;
}
/**
* Parses a YAML quoted scalar.
*
* @param string $scalar
* @param int &$i
*
* @return string
*
* @throws ParseException When malformed inline YAML string is parsed
*/
private static function parseQuotedScalar($scalar, &$i)
{
if (!Parser::preg_match('/'.self::REGEX_QUOTED_STRING.'/Au', substr($scalar, $i), $match)) {
throw new ParseException(sprintf('Malformed inline YAML string: %s.', substr($scalar, $i)));
}
$output = substr($match[0], 1, strlen($match[0]) - 2);
$unescaper = new Unescaper();
if ('"' == $scalar[$i]) {
$output = $unescaper->unescapeDoubleQuotedString($output);
} else {
$output = $unescaper->unescapeSingleQuotedString($output);
}
$i += strlen($match[0]);
return $output;
}
/**
* Parses a YAML sequence.
*
* @param string $sequence
* @param int $flags
* @param int &$i
* @param array $references
*
* @return array
*
* @throws ParseException When malformed inline YAML string is parsed
*/
private static function parseSequence($sequence, $flags, &$i = 0, $references = array())
{
$output = array();
$len = strlen($sequence);
++$i;
// [foo, bar, ...]
while ($i < $len) {
if (']' === $sequence[$i]) {
return $output;
}
if (',' === $sequence[$i] || ' ' === $sequence[$i]) {
++$i;
continue;
}
$tag = self::parseTag($sequence, $i, $flags);
switch ($sequence[$i]) {
case '[':
// nested sequence
$value = self::parseSequence($sequence, $flags, $i, $references);
break;
case '{':
// nested mapping
$value = self::parseMapping($sequence, $flags, $i, $references);
break;
default:
$isQuoted = in_array($sequence[$i], array('"', "'"));
$value = self::parseScalar($sequence, $flags, array(',', ']'), $i, null === $tag, $references);
// the value can be an array if a reference has been resolved to an array var
if (is_string($value) && !$isQuoted && false !== strpos($value, ': ')) {
// embedded mapping?
try {
$pos = 0;
$value = self::parseMapping('{'.$value.'}', $flags, $pos, $references);
} catch (\InvalidArgumentException $e) {
// no, it's not
}
}
--$i;
}
if (null !== $tag) {
$value = new TaggedValue($tag, $value);
}
$output[] = $value;
++$i;
}
throw new ParseException(sprintf('Malformed inline YAML string: %s.', $sequence));
}
/**
* Parses a YAML mapping.
*
* @param string $mapping
* @param int $flags
* @param int &$i
* @param array $references
*
* @return array|\stdClass
*
* @throws ParseException When malformed inline YAML string is parsed
*/
private static function parseMapping($mapping, $flags, &$i = 0, $references = array())
{
$output = array();
$len = strlen($mapping);
++$i;
// {foo: bar, bar:foo, ...}
while ($i < $len) {
switch ($mapping[$i]) {
case ' ':
case ',':
++$i;
continue 2;
case '}':
if (self::$objectForMap) {
return (object) $output;
}
return $output;
}
// key
$isKeyQuoted = in_array($mapping[$i], array('"', "'"), true);
$key = self::parseScalar($mapping, $flags, array(':', ' '), $i, false, array(), true);
if (':' !== $key && false === $i = strpos($mapping, ':', $i)) {
break;
}
if (':' === $key) {
@trigger_error('Omitting the key of a mapping is deprecated and will throw a ParseException in 4.0.', E_USER_DEPRECATED);
}
if (!(Yaml::PARSE_KEYS_AS_STRINGS & $flags)) {
$evaluatedKey = self::evaluateScalar($key, $flags, $references);
if ('' !== $key && $evaluatedKey !== $key && !is_string($evaluatedKey) && !is_int($evaluatedKey)) {
@trigger_error('Implicit casting of incompatible mapping keys to strings is deprecated since version 3.3 and will throw \Symfony\Component\Yaml\Exception\ParseException in 4.0. Pass the PARSE_KEYS_AS_STRINGS flag to explicitly enable the type casts.', E_USER_DEPRECATED);
}
}
if (':' !== $key && !$isKeyQuoted && (!isset($mapping[$i + 1]) || !in_array($mapping[$i + 1], array(' ', ',', '[', ']', '{', '}'), true))) {
@trigger_error('Using a colon after an unquoted mapping key that is not followed by an indication character (i.e. " ", ",", "[", "]", "{", "}") is deprecated since version 3.2 and will throw a ParseException in 4.0.', E_USER_DEPRECATED);
}
while ($i < $len) {
if (':' === $mapping[$i] || ' ' === $mapping[$i]) {
++$i;
continue;
}
$tag = self::parseTag($mapping, $i, $flags);
$duplicate = false;
switch ($mapping[$i]) {
case '[':
// nested sequence
$value = self::parseSequence($mapping, $flags, $i, $references);
// Spec: Keys MUST be unique; first one wins.
// Parser cannot abort this mapping earlier, since lines
// are processed sequentially.
if (isset($output[$key])) {
@trigger_error(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since version 3.2 and will throw \Symfony\Component\Yaml\Exception\ParseException in 4.0.', $key), E_USER_DEPRECATED);
$duplicate = true;
}
break;
case '{':
// nested mapping
$value = self::parseMapping($mapping, $flags, $i, $references);
// Spec: Keys MUST be unique; first one wins.
// Parser cannot abort this mapping earlier, since lines
// are processed sequentially.
if (isset($output[$key])) {
@trigger_error(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since version 3.2 and will throw \Symfony\Component\Yaml\Exception\ParseException in 4.0.', $key), E_USER_DEPRECATED);
$duplicate = true;
}
break;
default:
$value = self::parseScalar($mapping, $flags, array(',', '}'), $i, null === $tag, $references);
// Spec: Keys MUST be unique; first one wins.
// Parser cannot abort this mapping earlier, since lines
// are processed sequentially.
if (isset($output[$key])) {
@trigger_error(sprintf('Duplicate key "%s" detected whilst parsing YAML. Silent handling of duplicate mapping keys in YAML is deprecated since version 3.2 and will throw \Symfony\Component\Yaml\Exception\ParseException in 4.0.', $key), E_USER_DEPRECATED);
$duplicate = true;
}
--$i;
}
if (!$duplicate) {
if (null !== $tag) {
$output[$key] = new TaggedValue($tag, $value);
} else {
$output[$key] = $value;
}
}
++$i;
continue 2;
}
}
throw new ParseException(sprintf('Malformed inline YAML string: %s.', $mapping));
}
/**
* Evaluates scalars and replaces magic values.
*
* @param string $scalar
* @param int $flags
* @param array $references
*
* @return mixed The evaluated YAML string
*
* @throws ParseException when object parsing support was disabled and the parser detected a PHP object or when a reference could not be resolved
*/
private static function evaluateScalar($scalar, $flags, $references = array())
{
$scalar = trim($scalar);
$scalarLower = strtolower($scalar);
if (0 === strpos($scalar, '*')) {
if (false !== $pos = strpos($scalar, '#')) {
$value = substr($scalar, 1, $pos - 2);
} else {
$value = substr($scalar, 1);
}
// an unquoted *
if (false === $value || '' === $value) {
throw new ParseException('A reference must contain at least one character.');
}
if (!array_key_exists($value, $references)) {
throw new ParseException(sprintf('Reference "%s" does not exist.', $value));
}
return $references[$value];
}
switch (true) {
case 'null' === $scalarLower:
case '' === $scalar:
case '~' === $scalar:
return;
case 'true' === $scalarLower:
return true;
case 'false' === $scalarLower:
return false;
case $scalar[0] === '!':
switch (true) {
case 0 === strpos($scalar, '!str'):
return (string) substr($scalar, 5);
case 0 === strpos($scalar, '! '):
return (int) self::parseScalar(substr($scalar, 2), $flags);
case 0 === strpos($scalar, '!php/object:'):
if (self::$objectSupport) {
return unserialize(substr($scalar, 12));
}
if (self::$exceptionOnInvalidType) {
throw new ParseException('Object support when parsing a YAML file has been disabled.');
}
return;
case 0 === strpos($scalar, '!!php/object:'):
if (self::$objectSupport) {
@trigger_error('The !!php/object tag to indicate dumped PHP objects is deprecated since version 3.1 and will be removed in 4.0. Use the !php/object tag instead.', E_USER_DEPRECATED);
return unserialize(substr($scalar, 13));
}
if (self::$exceptionOnInvalidType) {
throw new ParseException('Object support when parsing a YAML file has been disabled.');
}
return;
case 0 === strpos($scalar, '!php/const:'):
if (self::$constantSupport) {
if (defined($const = substr($scalar, 11))) {
return constant($const);
}
throw new ParseException(sprintf('The constant "%s" is not defined.', $const));
}
if (self::$exceptionOnInvalidType) {
throw new ParseException(sprintf('The string "%s" could not be parsed as a constant. Have you forgotten to pass the "Yaml::PARSE_CONSTANT" flag to the parser?', $scalar));
}
return;
case 0 === strpos($scalar, '!!float '):
return (float) substr($scalar, 8);
case 0 === strpos($scalar, '!!binary '):
return self::evaluateBinaryScalar(substr($scalar, 9));
default:
@trigger_error(sprintf('Using the unquoted scalar value "%s" is deprecated since version 3.3 and will be considered as a tagged value in 4.0. You must quote it.', $scalar), E_USER_DEPRECATED);
}
// Optimize for returning strings.
case $scalar[0] === '+' || $scalar[0] === '-' || $scalar[0] === '.' || is_numeric($scalar[0]):
switch (true) {
case Parser::preg_match('{^[+-]?[0-9][0-9_]*$}', $scalar):
$scalar = str_replace('_', '', (string) $scalar);
// omitting the break / return as integers are handled in the next case
case ctype_digit($scalar):
$raw = $scalar;
$cast = (int) $scalar;
return '0' == $scalar[0] ? octdec($scalar) : (((string) $raw == (string) $cast) ? $cast : $raw);
case '-' === $scalar[0] && ctype_digit(substr($scalar, 1)):
$raw = $scalar;
$cast = (int) $scalar;
return '0' == $scalar[1] ? octdec($scalar) : (((string) $raw === (string) $cast) ? $cast : $raw);
case is_numeric($scalar):
case Parser::preg_match(self::getHexRegex(), $scalar):
$scalar = str_replace('_', '', $scalar);
return '0x' === $scalar[0].$scalar[1] ? hexdec($scalar) : (float) $scalar;
case '.inf' === $scalarLower:
case '.nan' === $scalarLower:
return -log(0);
case '-.inf' === $scalarLower:
return log(0);
case Parser::preg_match('/^(-|\+)?[0-9][0-9,]*(\.[0-9_]+)?$/', $scalar):
case Parser::preg_match('/^(-|\+)?[0-9][0-9_]*(\.[0-9_]+)?$/', $scalar):
if (false !== strpos($scalar, ',')) {
@trigger_error('Using the comma as a group separator for floats is deprecated since version 3.2 and will be removed in 4.0.', E_USER_DEPRECATED);
}
return (float) str_replace(array(',', '_'), '', $scalar);
case Parser::preg_match(self::getTimestampRegex(), $scalar):
if (Yaml::PARSE_DATETIME & $flags) {
// When no timezone is provided in the parsed date, YAML spec says we must assume UTC.
return new \DateTime($scalar, new \DateTimeZone('UTC'));
}
$timeZone = date_default_timezone_get();
date_default_timezone_set('UTC');
$time = strtotime($scalar);
date_default_timezone_set($timeZone);
return $time;
}
}
return (string) $scalar;
}
/**
* @param string $value
* @param int &$i
* @param int $flags
*
* @return null|string
*/
private static function parseTag($value, &$i, $flags)
{
if ('!' !== $value[$i]) {
return;
}
$tagLength = strcspn($value, " \t\n", $i + 1);
$tag = substr($value, $i + 1, $tagLength);
$nextOffset = $i + $tagLength + 1;
$nextOffset += strspn($value, ' ', $nextOffset);
// Is followed by a scalar
if (!isset($value[$nextOffset]) || !in_array($value[$nextOffset], array('[', '{'), true)) {
// Manage scalars in {@link self::evaluateScalar()}
return;
}
// Built-in tags
if ($tag && '!' === $tag[0]) {
throw new ParseException(sprintf('The built-in tag "!%s" is not implemented.', $tag));
}
if (Yaml::PARSE_CUSTOM_TAGS & $flags) {
$i = $nextOffset;
return $tag;
}
throw new ParseException(sprintf('Tags support is not enabled. Enable the `Yaml::PARSE_CUSTOM_TAGS` flag to use "!%s".', $tag));
}
/**
* @param string $scalar
*
* @return string
*
* @internal
*/
public static function evaluateBinaryScalar($scalar)
{
$parsedBinaryData = self::parseScalar(preg_replace('/\s/', '', $scalar));
if (0 !== (strlen($parsedBinaryData) % 4)) {
throw new ParseException(sprintf('The normalized base64 encoded data (data without whitespace characters) length must be a multiple of four (%d bytes given).', strlen($parsedBinaryData)));
}
if (!Parser::preg_match('#^[A-Z0-9+/]+={0,2}$#i', $parsedBinaryData)) {
throw new ParseException(sprintf('The base64 encoded data (%s) contains invalid characters.', $parsedBinaryData));
}
return base64_decode($parsedBinaryData, true);
}
private static function isBinaryString($value)
{
return !preg_match('//u', $value) || preg_match('/[^\x00\x07-\x0d\x1B\x20-\xff]/', $value);
}
/**
* Gets a regex that matches a YAML date.
*
* @return string The regular expression
*
* @see http://www.yaml.org/spec/1.2/spec.html#id2761573
*/
private static function getTimestampRegex()
{
return <<<EOF
~^
(?P<year>[0-9][0-9][0-9][0-9])
-(?P<month>[0-9][0-9]?)
-(?P<day>[0-9][0-9]?)
(?:(?:[Tt]|[ \t]+)
(?P<hour>[0-9][0-9]?)
:(?P<minute>[0-9][0-9])
:(?P<second>[0-9][0-9])
(?:\.(?P<fraction>[0-9]*))?
(?:[ \t]*(?P<tz>Z|(?P<tz_sign>[-+])(?P<tz_hour>[0-9][0-9]?)
(?::(?P<tz_minute>[0-9][0-9]))?))?)?
$~x
EOF;
}
/**
* Gets a regex that matches a YAML number in hexadecimal notation.
*
* @return string
*/
private static function getHexRegex()
{
return '~^0x[0-9a-f_]++$~i';
}
}