Looking for a way to simplify an if statement with multiple ||

Question

I have this JQuery / Javascript block of code to filter my list by search terms. It's very long and looks a little unprofessional. Is there a way I could simplify it?

Like with something ".contains()"?

If someone could point me in the right direction I'd greatly appreciate it. Thanks !

Heres the code; Ask me if you need more:

 $.each(catalog.products,
      function(index, value) {

          if ((filterValue == '' || filterValue == null)
                  || value.name.toUpperCase().indexOf(filterValue.toUpperCase()) != -1
                  || value.brand.toUpperCase().indexOf(filterValue.toLocaleUpperCase()) != -1
                  || value.category.toUpperCase().indexOf(filterValue.toUpperCase()) != -1
                  || value.sport.toUpperCase().indexOf(filterValue.toUpperCase()) != -1)
          {
              items.push('<li id="' + index + '">' +
                      '<a data-identity="productId"  href="./details.page?productId=' + index + '" >' +
                      '<img class="ui-li-thumb" src="' + value.thumbnail + '"/>' +
                      '<p>' + value.brand + '</p>' +
                      '<h3>' + value.name + '</h3>' +
                      '<span class="ui-li-count">' + value.price + ' $</span></li>') +
              '</a>';
          }

      }
        );

Answer 1

A straightforward way to 'simplify' the code would be

  var filterUpper = !filterValue || filterValue.toUpperCase();
  var test = function(s) {return s.toUpperCase().indexOf(filterUpper) != -1};

  if (!filterValue || test(value.name) || test(value.brand) || test(value.category) || test(value.sport))   {
   ...

Answer 2

I suggest you to read the following refactoring patterns:

• Decompose Conditional
• Consolidate Conditional Expression

The idea is that you're trying to infer something on that if statement, and it's not an 'indexOf' it's a business rule, try to give that rule a name and put the code in a method that expresses the intention.

just my 0.02

Answer 3

The first thing I would do is note that the following code snippet:

(filterValue == '' || filterValue == null)

can be changed to

!filterValue

This is because a null or empty string variable is considered 'falsy' in javascript, ie when considered as a boolean these values convert to false.

Then I would do as Alexander Gessler [1] has done and factor out the filterValue.toUpperCase() which is repeated.

[1] Looking for a way to simplify an if statement with multiple ||