Problems with lib-icu dependency when installing Symfony 2.3.x via Composer

update your php-intl extension, that's where the icu error comes from!

sudo aptitude install php5-intl                 // i.e. ubuntu
brew install icu4c                              // osx

check the extension is enabled and properly configured in php.ini aswell.

( hint: php-cli sometimes uses a different php.ini )

php.ini

extension=intl.so       ; *nix
extension=php_intl.dll  ; windows

[intl]
intl.default_locale = en_utf8
intl.error_level = E_WARNING

check your phpinfo() AND php -m from your terminal if the extension has been succesfully enabled.

Check your current intl versions from php with:

Intl::getIcuVersion();
Intl::getIcuDataVersion();

attention: not needed anymore ( symfony 2.3 has meanwhile been released )

add the minimum stability flag @dev or @rc to your dependency like this please:

composer create-project symfony/framework-standard-edition mynewerproject/ 2.3.*@dev 

The default stability in composer is stable which symfony 2.3 branch is not currently ( it's @rc ). Read more an stability flags here.

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Many applications will only be supporting "en" locale and will have no need for translation capabilities or php-intl. If this is you, or you can't install php-intl on your server, you can explicitly add symfony/icu ~1.0 to your composer.json. 1.0 does not require php-intl, whereas 1.1+ does.

If you don't need translation features:

$ php bin/composer.phar require symfony/icu ~1.0

Without this declaration and trying to install symfony/symfony 2.3 Composer may try to install symfony/icu ~1.2 which would require you to install php-intl.

This is explicitly covered more extensively in the Symfony Intl Component's docs under "ICU and Deployment Problems".

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A solution regarding this or similar problems can be found here: ICU and Deployment Problems

The behavior of composer should be intelligent selecting the right icu-component:

symfony/icu 1.0.*: when the intl extension is not available symfony/icu 1.1.*: when intl is compiled with ICU 4.0 or higher symfony/icu 1.2.*: when intl is compiled with ICU 4.4 or higher

There should be (theoretically) no error installing symfony 2.3. with no intl-extension.

But you can be trapped when your development-environment differs from your production-server like mentioned in this article:

the development machines are compiled with ICU 4.4 or higher, but the server is compiled >with a lower ICU version than 4.4 the intl extension is available on the development machines but not on the server.

When you have no root-access to your production-server you can fix it as mentioned in this article. (tweaking composer.json)

Hope this additional information helped as it helped me for this special case with different environments.

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Mac OS Mavericks comes with PHP 5.4.17 without intl. To get this, you'll have to follow those steps :

brew install icu4c
sudo pecl install intl 
The path to the ICU libraries and headers is: /usr/local/opt/icu4c/
Edit /etc/php.ini and add extension=intl.so to the end.

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I know that this answer may not be the correct answer to this person's problem, but it was the solution to my problem with the same title. I was able to fix this problem for myself by enabling the intl extension in php.ini and upgrading composer.

Upgrading composer.

php composer.phar self-update

Remove comment from this line (in php.ini):

extension=php_intl.dll

And also remove comment the these two lines below [intl] in (php.ini):

[intl]
intl.default_locale = en_utf8
intl.error_level = E_WARNING

And restart apache2 of course. :)

Additional Information:

If your using mac and installed php with Homebrew follow these steps:

(PHP 5.4)

$ brew install php54-intl

(PHP 5.5)

$ brew tap josegonzalez/php
$ brew tap homebrew/dupes
$ brew install josegonzalez/php/php55-intl
$ sudo apachectl restart

Restart apache.

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A better solution is to fix your composer.json to the version required by the production server. First, determine the ICU version on the server: 1 2

$ php -i | grep ICU
ICU version => 4.2.1

Then fix the Icu component in your composer.json file to a matching version:

"require: {
    "symfony/icu": "1.1.*"
}

Set the version to "1.0." if the server does not have the intl extension installed; "1.1." if the server is compiled with ICU 4.2 or lower.

Finally, run

php composer.phar update symfony/icu

on your development machine, test extensively and deploy again. The installation of the dependencies will now succeed.

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