Question

I want to unit test the return value of some code which looks similar to this:

Groovy Service code to test:
    def findByThisAndThat(something) {
            : 
        def items = []
        sql.eachRow(query, criteriaList, {
            def item = new Item(name:it.NAME)
            items.add(item)
        })
        [items: items, whatever:whatevervalue]
    }

Unit test code plan:

   void testFindByThisAndThatReturnsAMapContainingItems(){
       Sql.metaClass.eachRow = { String query, List criteria, Closure c ->

           // call closure to get passed in items list
           // add one new Item(name:"test item") to list
       }

       def result = service.findByThisAndThat("", "")

       assert result.items
       assertEquals('test item', result.items[0].name)
   }

How can I do that?
Thanks!

Answer 1

Call the closure by using it like a method. Alternatively, you can use Closure.call() as well. Pass in the value for it as the first parameter.

Sql.metaClass.eachRow = { String query, List criteria, Closure c ->
    def mockItems = ["test item"]
    mockItems.each { item ->
        c(item)
        // c.call(item) works too
    }
}

Note that the Sql metaClass won’t get reset at the end of the test. I’d recommend clearing it out after the test:

Sql.metaClass = null