https://github.com/duodraco/phpcs-psr

CodeSniffer for PSR's

This is a PHP_CodeSniffer sniff to check against the PHP Standard Resolutions: PSR-0, PSR-1 and PSR-2. Those standards were approved by the PHP Framework Interoperability Group.

You can read more about the PHP FIG and the PSR's on this excellent article by Paul Jones.
PSR-1 Overview

    Files MUST use only <?php and <?= tags.

    Files MUST use only UTF-8 without BOM for PHP code.

    Files SHOULD either declare symbols (classes, functions, constants, etc.) or cause side-effects (e.g. generate output, change .ini settings, etc.) but SHOULD NOT do both.

    Namespaces and classes MUST follow PSR-0.

    Class names MUST be declared in StudlyCaps.

    Class constants MUST be declared in all upper case with underscore separators.

    Method names MUST be declared in camelCase.

PSR-2 Overview

    Code MUST follow PSR-1.

    Code MUST use 4 spaces for indenting, not tabs.

    There MUST NOT be a hard limit on line length; the soft limit MUST be 120 characters; lines SHOULD be 80 characters or less.

    There MUST be one blank line after the namespace declaration, and there MUST be one blank line after the block of use declarations.

    Opening braces for classes MUST go on the next line, and closing braces MUST go on the next line after the body.

    Opening braces for methods MUST go on the next line, and closing braces MUST go on the next line after the body.

    Visibility MUST be declared on all properties and methods; abstract and final MUST be declared before the visibility; static MUST be declared after the visibility.

    Control structure keywords MUST have one space after them; method and function calls MUST NOT.

    Opening braces for control structures MUST go on the same line, and closing braces MUST go on the next line after the body.

    Opening parentheses for control structures MUST NOT have a space after them, and closing parentheses for control structures MUST NOT have a space before.

How to use

    Install CodeSniffer:

    pear install PHP_CodeSniffer

    Clone this repository to a folder called PSR inside your CodeSniffer Standards directory (eg.: /usr/share/php/PHP/CodeSniffer/Standards)

    cd /usr/share/php/PHP/CodeSniffer/Standards
    git clone https://github.com/klaussilveira/phpcs-psr PSR

    Set PSR as the default sniff for CodeSniffer:

    phpcs --config-set default_standard PSR


for more information:
https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-1-basic-coding-standard.md
https://github.com/php-fig/fig-standards/blob/master/accepted/PSR-2-coding-style-guide.md
http://www.cheatography.com/davechild/cheat-sheets/php-fig-psr-standards/