node_modules/oboe/test/libs/listMatcher.js

function listMatcher(expectedList){
          
   return eq.call( this, this.actual, expectedList );
 
   function eq( actual, expected ) {
   
      if( !actual && !expected ) {
         return true;
      }
      
      if( !actual || !expected ) {
         this.message = function(){
            return 'one false but not both ' +
                     actual + ' ' + expected
         };               
         return false;
      }
      
      if( head(actual) != head(expected) ) {
         this.message = function(){
            return 'different items in list' +
                     head(actual) + head(expected)
         }; 
         return false;
      }
      
      return eq.call( this, tail(actual), tail(expected) );
   }
}