phpcs_example.xml

<?xml version="1.0"?>
<ruleset name="Variable Analysis">
 <description>Copy this to your ~/phpcs.xml after doing composer require --global ksjogo/variable-analysis.</description>

 <!-- If you want everything, with the defaults, just include this line -->
 <rule ref="VariableAnalysis"/>

 <!-- Or iclude this block to customize VariableAnalysis behaviour -->
 <rule ref="VariableAnalysis.VariableAnalysis.VariableAnalysis">
   <properties>
  <!--
     We are not doing any deep analysis, so we cannot check nested instance variables etc.
     Just allow them.
  -->
   <property name="allowInstanceVariables" value="false"/>
    <!--
      Include the following property if you want to include your own list of pass-by-reference
      functions defined in your codebase.
      Format is "function:argnum" or "function:argnum1,argnum2" etc.
      Whitespace delimits function definitions.
      Argument numbers start at 1 and an elipsis '...' means all argument numbers
      after the previous should be considered pass-by-reference.
   -->
   <property name="sitePassByRefFunctions" value="
    function_with_first_arg_by_ref:1
    function_with_second_and_third_arg_by_ref:2,3
    function_with_third_and_remaining_args_by_ref:3,...
    "/>
   <!--
      Include the following property if you want to prevent exception variables declared
      in a catch block from causing an unused variable warning, this supports the common
      (but not always wanted) pattern of:
        try {
            // stuff here
        } catch (Exception $e) {
            // Do something without ever using $e
        }
   -->
   <property name="allowUnusedCaughtExceptions" value="1"/>
   <!--
      Include the following property if you want to prevent function parametets from causing an
      unused variable warning, this supports the common pattern of defining callback functions that
      demand a fixed parameter list without actually using all the paramets.
        function foo ($a, $b, $c) {
            // Do something without ever using some of $a, $b and/or $c
        }
   -->
   <property name="allowUnusedFunctionParameters" value="1"/>
   <!--
      Include the following property if you want to have a whitelist of variable names
      that are commonly used for placeholder "junk" values that ignored and that you
      don't want to provoke an unused variable warning for.
      Format is "variableName" without a leading $ with whitespace delimiting names.
   -->
   <property name="validUnusedVariableNames" value="
    junk
    dummy
    "/>
  <!--
     Include the following property if you want to have a whitelist of variable names
     that are defined in all php files and that you don't want to provoke an undefined
     variable warning for.
     Format is "variableName" without a leading $ with whitespace delimiting names.
  -->
   <property name="validUndefinedVariableNames" value="
    junk
    dummy
    "/>
  </properties>
 </rule>
</ruleset>