code: function( name, handle ) {
  		var self = this;
  
  		// Can only add custom assertions when module hasn't been triggered yet
  		self.requireMaxState( munit.ASSERT_STATE_DEFAULT, self.custom );
  
  		// Block on reserved words
  		if ( munit.customReserved.indexOf( name ) > -1 ) {
  			throw new Error( "'" + name + "' is a reserved name and cannot be added as a custom assertion test" );
  		}
  
  		// Attach handle to assertion module and all submodules
  		self[ name ] = handle;
  		munit.each( self.ns, function( mod ) {
  			mod.custom( name, handle );
  		});
  
  		return self;
  	}
docs: Custom test additions