如何对与DOM元素交互的Javascript代码进行单元测试

Question

背景:

我来自Java背景,所以不太熟悉Javascript.

我们计划对现有(遗留)代码和未来工作引入JavaScript单元测试.我们主要是一家java商店(Spring,Weblogic等).

我们正在寻找能够与IDE(IntelliJ构思)和声纳良好集成的选项,以及能够将它们作为持续集成的一部分运行.

JsTestDriver似乎勾选了所有方框.

题:

我们现有的许多javascript代码是a)嵌入在JSP中,b)利用jQuery直接与页面元素进行交互.

我们应该如何测试严重依赖于DOM的函数.这是我正在谈论的函数的一些代码示例:

function enableOccupationDetailsText (){
    $( "#fldOccupation" ).val("Unknown");
    $( "#fldOccupation_Details" ).attr("disabled", "");
    $( "#fldOccupation_Details" ).val("");
    $( "#fldOccupation_Details" ).focus();
}

要么

jQuery(document).ready(function(){

    var oTable = $('#policies').dataTable( {
            "sDom" : 'frplitip',
                "bProcessing": true,
                "bServerSide": true,
                "sAjaxSource": "xxxx.do",
                "sPaginationType": "full_numbers",
                "aaSorting": [[ 1, "asc" ]],
                "oLanguage": {
                    "sProcessing":   "Processing...",
                    "sLengthMenu":   "Show _MENU_ policies",
                    "sZeroRecords":  "No matching policies found",
                    "sInfo":         "Showing _START_ to _END_ of _TOTAL_ policies",
                    "sInfoEmpty":    "Showing 0 to 0 of 0 policies",
                    "sInfoFiltered": "(filtered from _MAX_ total policies)",
                    "sInfoPostFix":  "",
                    "sSearch":       "Search:",
                    "sUrl":          "",
                    "oPaginate": {
                        "sFirst":    "First",
                        "sPrevious": "Previous",
                        "sNext":     "Next",
                        "sLast":     "Last"
                }
            },
                "fnRowCallback": function( nRow, aData, iDisplayIndex, iDisplayIndexFull ) {
                        $('td:eq(0)', nRow).html( "<a href='/ole/policy/general_details.do?policy_id="+aData[0]+"'>"+aData[0]+"</a>" );
                        return nRow;

                },

                "fnServerData" : function ( url, data, callback, settings ) {

                settings.jqXHR = $.ajax( {
                    "url": url,
                    "data": data,
                    "success": function (json) {
                        if (json.errorMessage != null) {
                            var an = settings.aanFeatures.r;
                            an[0].style.fontSize="18px";
                            an[0].style.backgroundColor="red";
                            an[0].style.height="70px";
                            an[0].innerHTML=json.errorMessage;
                            setTimeout('window.location="/xxxx"',1000);
                            //window.location="/xxxxx";
                        } else {
                            $(settings.oInstance).trigger('xhr', settings);
                            callback( json );
                        }
                    },
                    "dataType": "json",
                    "cache": false,
                    "error": function (xhr, error, thrown) {
                        if ( error == "parsererror" ) {
                            alert( "Unexpected error, please contact system administrator. Press OK to be redirected to home page." );
                            window.location="/xxxx";
                        }
                    }
                } );
                }

            } );
        $("#policies_filter :text").attr('id', 'fldKeywordSearch');
        $("#policies_length :input").attr('id', 'fldNumberOfRows');
        $("body").find("span > span").css("border","3px solid red");
        oTable.fnSetFilteringDelay(500);
        oTable.fnSearchHighlighting();
        $("#fldKeywordSearch").focus();

}
);

在后一种情况下,我的方法是所讨论的函数太大而且应该被打破到较小的(单位),以便可以对其进行测试.但是所有与DOM,jQuery,datatables,ajax等的交互点使得以我们在Java世界中的方式重构事物以使其更易于测试变得非常复杂.

因此,非常感谢上述样本案例的任何建议!

Answer 1

要测试以下代码:

function enableOccupationDetailsText (){
    $( "#fldOccupation" ).val("Unknown");
    $( "#fldOccupation_Details" ).attr("disabled", "");
    $( "#fldOccupation_Details" ).val("");
    $( "#fldOccupation_Details" ).focus();
}

您可以使用以下代码:

// First, create the elements
$( '<input>', { id: 'fldOccupation' } ).appendTo( document.body );
$( '<input>', { disabled: true, id: 'fldOccupation_Details' } )
    .appendTo( document.body );

// Then, run the function to test
enableOccupationDetailsText();

// And test
assert( $( '#fldOccupation' ).val(), 'Unknown' );
assert( $( '#fldOccupation_Details' ).prop( 'disabled' ), false );

如你所见,它只是经典setup > run > assert模式.