Laravel: Call to undefined function Symfony\Component\Console\mb_convert_variables()?

问题

I'm running a vanilla Amazon EC2 server. I installed PHP 5.5.21 myself. My web application is built on Laravel. For weeks, everything was working flawlessly. Now, however, when running the Laravel command to update the database schema:

php artisan migrate

I get the following error:

PHP Fatal error: Call to undefined function Symfony\Component\Console\mb_convert_variables() in /var/www/mysite/vendor/symfony/console/Symfony/Component/Console/Application.php on line 1154

Oddly, I haven't made any updates or installed any packages between the time it was working and when it ceased to work. (At least I think. I checked my history to be sure.)

I don't believe that this is an issue with Laravel, per se. My research suggests that mb_convert_variables is supposed to be a built-in PHP function.

Here's line 1154 of Application.php that is throwing the error:

mb_convert_variables($encoding, 'utf8', $lines);

And here is it in the larger context. It's interesting the mb_convert_encoding(...) seems to be working fine:

private function splitStringByWidth($string, $width)
{
    // str_split is not suitable for multi-byte characters, we should use preg_split to get char array properly.
    // additionally, array_slice() is not enough as some character has doubled width.
    // we need a function to split string not by character count but by string width

    if (!function_exists('mb_strwidth')) {
        return str_split($string, $width);
    }

    if (false === $encoding = mb_detect_encoding($string)) {
        return str_split($string, $width);
    }

    $utf8String = mb_convert_encoding($string, 'utf8', $encoding);
    $lines = array();
    $line = '';
    foreach (preg_split('//u', $utf8String) as $char) {
        // test if $char could be appended to current line
        if (mb_strwidth($line.$char, 'utf8') <= $width) {
            $line .= $char;
            continue;
        }
        // if not, push current line to array and make new line
        $lines[] = str_pad($line, $width);
        $line = $char;
    }
    if (strlen($line)) {
        $lines[] = count($lines) ? str_pad($line, $width) : $line;
    }

    mb_convert_variables($encoding, 'utf8', $lines);

    return $lines;
}

I'm not sure if this is helpful, but here's a list of all installed PHP modules:

[PHP Modules]
bz2
calendar
Core
ctype
curl
date
dom
ereg
exif
fileinfo
filter
ftp
gettext
hash
iconv
json
libxml
mcrypt
mhash
mysql
mysqli
mysqlnd
openssl
pcntl
pcre
PDO
pdo_mysql
pdo_sqlite
Phar
posix
readline
Reflection
session
shmop
SimpleXML
sockets
SPL
sqlite3
standard
sysvmsg
sysvsem
sysvshm
tokenizer
wddx
xml
xmlreader
xmlwriter
xsl
zip
zlib

And here's some of the output of php -i:

phpinfo()
PHP Version => 5.5.21

System => Linux ip-172-31-6-34 3.14.26-24.46.amzn1.x86_64 #1 SMP Wed Dec 10 10:02:43 UTC 2014 x86_64
Build Date => Feb 11 2015 23:17:00
Server API => Command Line Interface
Virtual Directory Support => disabled
Configuration File (php.ini) Path => /etc
Loaded Configuration File => /etc/php.ini
Scan this dir for additional .ini files => /etc/php-5.5.d
Additional .ini files parsed => /etc/php-5.5.d/bz2.ini,
/etc/php-5.5.d/calendar.ini,
/etc/php-5.5.d/ctype.ini,
/etc/php-5.5.d/curl.ini,
/etc/php-5.5.d/dom.ini,
/etc/php-5.5.d/exif.ini,
/etc/php-5.5.d/fileinfo.ini,
/etc/php-5.5.d/ftp.ini,
/etc/php-5.5.d/gettext.ini,
/etc/php-5.5.d/iconv.ini,
/etc/php-5.5.d/json.ini,
/etc/php-5.5.d/mcrypt.ini,
/etc/php-5.5.d/mysqlnd.ini,
/etc/php-5.5.d/mysqlnd_mysql.ini,
/etc/php-5.5.d/mysqlnd_mysqli.ini,
/etc/php-5.5.d/pdo.ini,
/etc/php-5.5.d/pdo_mysqlnd.ini,
/etc/php-5.5.d/pdo_sqlite.ini,
/etc/php-5.5.d/phar.ini,
/etc/php-5.5.d/php.ini,
/etc/php-5.5.d/posix.ini,
/etc/php-5.5.d/shmop.ini,
/etc/php-5.5.d/simplexml.ini,
/etc/php-5.5.d/sockets.ini,
/etc/php-5.5.d/sqlite3.ini,
/etc/php-5.5.d/sysvmsg.ini,
/etc/php-5.5.d/sysvsem.ini,
/etc/php-5.5.d/sysvshm.ini,
/etc/php-5.5.d/tokenizer.ini,
/etc/php-5.5.d/xml.ini,
/etc/php-5.5.d/xml_wddx.ini,
/etc/php-5.5.d/xmlreader.ini,
/etc/php-5.5.d/xmlwriter.ini,
/etc/php-5.5.d/xsl.ini,
/etc/php-5.5.d/zip.ini

PHP API => 20121113
PHP Extension => 20121212
Zend Extension => 220121212
Zend Extension Build => API220121212,NTS
PHP Extension Build => API20121212,NTS
Debug Build => no
Thread Safety => disabled
Zend Signal Handling => disabled
Zend Memory Manager => enabled
Zend Multibyte Support => disabled
IPv6 Support => enabled
DTrace Support => enabled

Registered PHP Streams => https, ftps, compress.zlib, php, file, glob, data, http, ftp, compress.bzip2, phar, zip
Registered Stream Socket Transports => tcp, udp, unix, udg, ssl, sslv3, sslv2, tls
Registered Stream Filters => zlib.*, string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed, dechunk, bzip2.*, convert.iconv.*, mcrypt.*, mdecrypt.*



Core

PHP Version => 5.5.21

Directive => Local Value => Master Value
allow_url_fopen => On => On
allow_url_include => Off => Off
always_populate_raw_post_data => Off => Off
arg_separator.input => & => &
arg_separator.output => & => &
asp_tags => Off => Off
auto_append_file => no value => no value
auto_globals_jit => On => On
auto_prepend_file => no value => no value
browscap => no value => no value
default_charset => no value => no value
default_mimetype => text/html => text/html
disable_classes => no value => no value
disable_functions => no value => no value
display_errors => Off => Off
display_startup_errors => Off => Off
doc_root => no value => no value
docref_ext => no value => no value
docref_root => no value => no value
enable_dl => Off => Off
enable_post_data_reading => On => On
error_append_string => no value => no value
error_log => no value => no value
error_prepend_string => no value => no value
error_reporting => 22527 => 22527
exit_on_timeout => Off => Off
expose_php => On => On
extension_dir => /usr/lib64/php/5.5/modules => /usr/lib64/php/5.5/modules
file_uploads => On => On
highlight.comment => <font style="color: #FF8000">#FF8000</font> => <font style="color: #FF8000">#FF8000</font>
highlight.default => <font style="color: #0000BB">#0000BB</font> => <font style="color: #0000BB">#0000BB</font>
highlight.html => <font style="color: #000000">#000000</font> => <font style="color: #000000">#000000</font>
highlight.keyword => <font style="color: #007700">#007700</font> => <font style="color: #007700">#007700</font>
highlight.string => <font style="color: #DD0000">#DD0000</font> => <font style="color: #DD0000">#DD0000</font>
html_errors => Off => Off
ignore_repeated_errors => Off => Off
ignore_repeated_source => Off => Off
ignore_user_abort => Off => Off
implicit_flush => On => On
include_path => .:/usr/share/pear:/usr/share/php => .:/usr/share/pear:/usr/share/php
log_errors => On => On
log_errors_max_len => 1024 => 1024
mail.add_x_header => On => On
mail.force_extra_parameters => no value => no value
mail.log => no value => no value
max_execution_time => 0 => 0
max_file_uploads => 20 => 20
max_input_nesting_level => 64 => 64
max_input_time => -1 => -1
max_input_vars => 1000 => 1000
memory_limit => 128M => 128M
open_basedir => no value => no value
output_buffering => 0 => 0
output_handler => no value => no value
post_max_size => 8M => 8M
precision => 14 => 14
realpath_cache_size => 16K => 16K
realpath_cache_ttl => 120 => 120
register_argc_argv => On => On
report_memleaks => On => On
report_zend_debug => Off => Off
request_order => GP => GP
sendmail_from => no value => no value
sendmail_path => /usr/sbin/sendmail -t -i => /usr/sbin/sendmail -t -i
serialize_precision => 17 => 17
short_open_tag => Off => Off
SMTP => localhost => localhost
smtp_port => 25 => 25
sql.safe_mode => Off => Off
sys_temp_dir => no value => no value
track_errors => Off => Off
unserialize_callback_func => no value => no value
upload_max_filesize => 2M => 2M
upload_tmp_dir => no value => no value
user_dir => no value => no value
user_ini.cache_ttl => 300 => 300
user_ini.filename => .user.ini => .user.ini
variables_order => GPCS => GPCS
xmlrpc_error_number => 0 => 0
xmlrpc_errors => Off => Off
zend.detect_unicode => On => On
zend.enable_gc => On => On
zend.multibyte => Off => Off
zend.script_encoding => no value => no value

ctype

ctype functions => enabled



ereg

Regex Library => Bundled library enabled

exif

EXIF Support => enabled
EXIF Version => 1.4 $Id: 7f95ff43ea7cc9a2c41a912863ed70069c0e34c5 $
Supported EXIF Version => 0220
Supported filetypes => JPEG,TIFF

Directive => Local Value => Master Value
exif.decode_jis_intel => JIS => JIS
exif.decode_jis_motorola => JIS => JIS
exif.decode_unicode_intel => UCS-2LE => UCS-2LE
exif.decode_unicode_motorola => UCS-2BE => UCS-2BE
exif.encode_jis => no value => no value
exif.encode_unicode => ISO-8859-15 => ISO-8859-15

fileinfo

fileinfo support => enabled
version => 1.0.5

filter

Input Validation and Filtering => enabled
Revision => $Id: 4d3899e089e6e45b157975ceef2ac7deb6e9d762 $

Directive => Local Value => Master Value
filter.default => unsafe_raw => unsafe_raw
filter.default_flags => no value => no value

ftp

FTP support => enabled

gettext

GetText Support => enabled

hash

hash support => enabled
Hashing Engines => md2 md4 md5 sha1 sha224 sha256 sha384 sha512 ripemd128 ripemd160 ripemd256 ripemd320 whirlpool tiger128,3 tiger160,3 tiger192,3 tiger128,4 tiger160,4 tiger192,4 snefru snefru256 gost adler32 crc32 crc32b fnv132 fnv164 joaat haval128,3 haval160,3 haval192,3 haval224,3 haval256,3 haval128,4 haval160,4 haval192,4 haval224,4 haval256,4 haval128,5 haval160,5 haval192,5 haval224,5 haval256,5

iconv

iconv support => enabled
iconv implementation => glibc
iconv library version => 2.17

Directive => Local Value => Master Value
iconv.input_encoding => ISO-8859-1 => ISO-8859-1
iconv.internal_encoding => ISO-8859-1 => ISO-8859-1
iconv.output_encoding => ISO-8859-1 => ISO-8859-1

json

json support => enabled
json version => 1.3.6
JSON-C headers version => 0.11
JSON-C library version => 0.11

libxml

libXML support => active
libXML Compiled Version => 2.9.1
libXML Loaded Version => 20901
libXML streams => enabled

mcrypt

mcrypt support => enabled
mcrypt_filter support => enabled
Version => 2.5.8
Api No => 20021217
Supported ciphers => cast-128 gost rijndael-128 twofish arcfour cast-256 loki97 rijndael-192 saferplus wake blowfish-compat des rijndael-256 serpent xtea blowfish enigma rc2 tripledes
Supported modes => cbc cfb ctr ecb ncfb nofb ofb stream

Directive => Local Value => Master Value
mcrypt.algorithms_dir => no value => no value
mcrypt.modes_dir => no value => no value

mhash

MHASH support => Enabled
MHASH API Version => Emulated Support


openssl

OpenSSL support => enabled
OpenSSL Library Version => OpenSSL 1.0.1k-fips 8 Jan 2015
OpenSSL Header Version => OpenSSL 1.0.1k-fips 8 Jan 2015

pcntl

pcntl support => enabled

pcre

PCRE (Perl Compatible Regular Expressions) Support => enabled
PCRE Library Version => 8.21 2011-12-12

Directive => Local Value => Master Value
pcre.backtrack_limit => 1000000 => 1000000
pcre.recursion_limit => 100000 => 100000

PDO

PDO support => enabled
PDO drivers => mysql, sqlite

pdo_mysql

PDO Driver for MySQL => enabled
Client API version => mysqlnd 5.0.11-dev - 20120503 - $Id: bf9ad53b11c9a57efdb1057292d73b928b8c5c77 $

Directive => Local Value => Master Value
pdo_mysql.default_socket => /var/lib/mysql/mysql.sock => /var/lib/mysql/mysql.sock

pdo_sqlite

PDO Driver for SQLite 3.x => enabled
SQLite Library => 3.7.17

Phar

Phar: PHP Archive support => enabled
Phar EXT version => 2.0.2
Phar API version => 1.1.1
SVN revision => $Id: cc0fad28eb9ea42466f756c3b5fc22c764e32690 $
Phar-based phar archives => enabled
Tar-based phar archives => enabled
ZIP-based phar archives => enabled
gzip compression => enabled
bzip2 compression => enabled
Native OpenSSL support => enabled


Phar based on pear/PHP_Archive, original concept by Davey Shafik.
Phar fully realized by Gregory Beaver and Marcus Boerger.
Portions of tar implementation Copyright (c) 2003-2009 Tim Kientzle.
Directive => Local Value => Master Value
phar.cache_list => no value => no value
phar.readonly => On => On
phar.require_hash => On => On

posix

Revision => $Id: 1dfa9997ed76804e53c91e0ce862f3707617b6ed $

readline

Readline Support => enabled
Readline library => EditLine wrapper

Directive => Local Value => Master Value
cli.pager => no value => no value
cli.prompt => \b \>  => \b \>

Reflection

Reflection => enabled
Version => $Id: 95b780d3f0d017feba96a5c35cca9541186114ad $

session

Session Support => enabled
Registered save handlers => files user
Registered serializer handlers => php_serialize php php_binary wddx

Directive => Local Value => Master Value
session.auto_start => Off => Off
session.cache_expire => 180 => 180
session.cache_limiter => nocache => nocache
session.cookie_domain => no value => no value
session.cookie_httponly => Off => Off
session.cookie_lifetime => 0 => 0
session.cookie_path => / => /
session.cookie_secure => Off => Off
session.entropy_file => /dev/urandom => /dev/urandom
session.entropy_length => 32 => 32
session.gc_divisor => 1000 => 1000
session.gc_maxlifetime => 1440 => 1440
session.gc_probability => 1 => 1
session.hash_bits_per_character => 5 => 5
session.hash_function => 0 => 0
session.name => PHPSESSID => PHPSESSID
session.referer_check => no value => no value
session.save_handler => files => files
session.save_path => no value => no value
session.serialize_handler => php => php
session.upload_progress.cleanup => On => On
session.upload_progress.enabled => On => On
session.upload_progress.freq => 1% => 1%
session.upload_progress.min_freq => 1 => 1
session.upload_progress.name => PHP_SESSION_UPLOAD_PROGRESS => PHP_SESSION_UPLOAD_PROGRESS
session.upload_progress.prefix => upload_progress_ => upload_progress_
session.use_cookies => On => On
session.use_only_cookies => On => On
session.use_strict_mode => Off => Off
session.use_trans_sid => 0 => 0

shmop

shmop support => enabled

SimpleXML

Simplexml support => enabled
Revision => $Id: a915862ec47f9589309acc4996ca8f6179788746 $
Schema support => enabled

sockets

Sockets Support => enabled

SPL

SPL support => enabled
Interfaces => Countable, OuterIterator, RecursiveIterator, SeekableIterator, SplObserver, SplSubject
Classes => AppendIterator, ArrayIterator, ArrayObject, BadFunctionCallException, BadMethodCallException, CachingIterator, CallbackFilterIterator, DirectoryIterator, DomainException, EmptyIterator, FilesystemIterator, FilterIterator, GlobIterator, InfiniteIterator, InvalidArgumentException, IteratorIterator, LengthException, LimitIterator, LogicException, MultipleIterator, NoRewindIterator, OutOfBoundsException, OutOfRangeException, OverflowException, ParentIterator, RangeException, RecursiveArrayIterator, RecursiveCachingIterator, RecursiveCallbackFilterIterator, RecursiveDirectoryIterator, RecursiveFilterIterator, RecursiveIteratorIterator, RecursiveRegexIterator, RecursiveTreeIterator, RegexIterator, RuntimeException, SplDoublyLinkedList, SplFileInfo, SplFileObject, SplFixedArray, SplHeap, SplMinHeap, SplMaxHeap, SplObjectStorage, SplPriorityQueue, SplQueue, SplStack, SplTempFileObject, UnderflowException, UnexpectedValueException


standard

Dynamic Library Support => enabled
Path to sendmail => /usr/sbin/sendmail -t -i

Directive => Local Value => Master Value
assert.active => 1 => 1
assert.bail => 0 => 0
assert.callback => no value => no value
assert.quiet_eval => 0 => 0
assert.warning => 1 => 1
auto_detect_line_endings => 0 => 0
default_socket_timeout => 60 => 60
from => no value => no value
url_rewriter.tags => a=href,area=href,frame=src,input=src,form=fakeentry => a=href,area=href,frame=src,input=src,form=fakeentry
user_agent => no value => no value

sysvmsg

sysvmsg support => enabled
Revision => $Id: adf1d2d6be849c46eed3c3ee6f1cbebd1448d6e5 $

tokenizer

Tokenizer Support => enabled

wddx

WDDX Support => enabled
WDDX Session Serializer => enabled

xml

XML Support => active
XML Namespace Support => active
libxml2 Version => 2.9.1

xmlreader

XMLReader => enabled

xmlwriter

XMLWriter => enabled

xsl

XSL => enabled
libxslt Version => 1.1.28
libxslt compiled against libxml Version => 2.9.1
EXSLT => enabled
libexslt Version => 1.1.28

zip

Zip => enabled
Extension Version => $Id: 05dd1ecc211075107543b0ef8cee488dd229fccf $
Zip version => 1.11.0
Compiled against libzip version => 0.10.1

zlib

ZLib Support => enabled
Stream Wrapper => compress.zlib://
Stream Filter => zlib.inflate, zlib.deflate
Compiled Version => 1.2.7
Linked Version => 1.2.7

Directive => Local Value => Master Value
zlib.output_compression => Off => Off
zlib.output_compression_level => -1 => -1
zlib.output_handler => no value => no value

Additional Modules

Module Name
sysvsem
sysvshm

I have a few questions regarding this: