error.txt

Uncaught TypeError: Illegal invocation
    at add (jquery.js:8260)
    at buildParams (jquery.js:8247)
    at buildParams (jquery.js:8241)
    at buildParams (jquery.js:8241)
    at buildParams (jquery.js:8241)
    at buildParams (jquery.js:8241)
    at Function.jQuery.param (jquery.js:8280)
    at Function.ajax (jquery.js:8866)
    at HTMLButtonElement.<anonymous> (funcoes.js:6855)
    at HTMLDocument.dispatch (jquery.js:5110)

Illegal_invocation.js

$(function(){
    $(document).on('click', '#add_certi', function(){
        let array;
        let idLote = $('#id_lote').val();
        let idUnidade = $('#id_unidade').val();
        let idGrupo = $('#id_grupo').val();
        $("#loader").show().fadeTo('fast', 1);
        $('#add_certificado').fadeTo( "slow" , 0.15);
        array = $('input:checked').map(function(){
            return this.value;
        });
        $.ajax({
            type:"POST",
            url: '/vincula-certificado',
            data:{array, idLote, idUnidade, idGrupo},
            success: function(result){
                $("#loader").hide();
                $('#add_certificado').fadeTo("slow", 1);
             }
        });
    });
});

linha _do_erro.js

// Serialize an array of form elements or a set of
// key/values into a query string
jQuery.param = function( a, traditional ) {
	var prefix,
		s = [],
		add = function( key, valueOrFunction ) {

			// If value is a function, invoke it and use its return value
			var value = jQuery.isFunction( valueOrFunction ) ?
				valueOrFunction() ://AQUI ELE ME RETORNA O ERRO DE ILLEGAL INVOCATION
				valueOrFunction;

			s[ s.length ] = encodeURIComponent( key ) + "=" +
				encodeURIComponent( value == null ? "" : value );
		};

	// If an array was passed in, assume that it is an array of form elements.
	if ( jQuery.isArray( a ) || ( a.jquery && !jQuery.isPlainObject( a ) ) ) {

		// Serialize the form elements
		jQuery.each( a, function() {
			add( this.name, this.value );
		} );

	} else {

		// If traditional, encode the "old" way (the way 1.3.2 or older
		// did it), otherwise encode params recursively.
		for ( prefix in a ) {
			buildParams( prefix, a[ prefix ], traditional, add );
		}
	}

	// Return the resulting serialization
	return s.join( "&" );
};