php - Error while executing assetic dump (parse error: failed at `&:extend(.clearfix all);`)

Question

I was trying to install bootstrap to symfony2. Everything went well until I tried the assetic:dump --force command.

Here's my assetic configuration"

# Assetic Configuration
assetic:
    debug:          %kernel.debug%
    use_controller: false
    bundles:        [ ]
    java: /usr/bin/java
    filters:
        cssrewrite: ~
        cssembed:
          jar: %kernel.root_dir%/Resources/java/cssembed-0.4.5.jar
        yui_js:
          jar: %kernel.root_dir%/Resources/java/yuicompressor.jar
        lessphp:
          file: %kernel.root_dir%/../vendor/leafo/lessphp/lessc.inc.php
          apply_to: ".less$"
    assets:
        jquery_js:
            inputs:
                - '%kernel.root_dir%/../components/jquery/jquery.min.js'
            filters: [?yui_js]
        bootstrap_js:
            inputs:
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/transition.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/alert.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/modal.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/dropdown.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/scrollspy.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/tab.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/tooltip.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/popover.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/button.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/collapse.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/carousel.js'
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/js/affix.js'
            filters: [?yui_js]
        bootstrap_less:
            inputs:
                - '%kernel.root_dir%/../vendor/twitter/bootstrap/less/bootstrap.less'
            filters: [lessphp,cssembed]

Answer 1

I had the same issue. I resolved it changing the "leafo/lessphp" version in composer.json:

From:

 "leafo/lessphp": "~0.3"

to:

 "leafo/lessphp": "~0.3.9"