NO DML after Test.Start() but still getting System.CalloutException: You have uncommitted work pending

Question

Basically, I'm getting the dreaded "System.CalloutException: You have uncommitted work pending." exception even though I'm 99.999% sure I'm not making any DML statements after running Test.startTest().

I've reduced my test to the simplest form and am still getting the error.

 @isTest static void test_WTFSALESFORCE() {

    abc__c abc = new abc__c(
            Name = 'test'); 
    insert abc;

    //set mock
    MockHttpResponseGenerator mock = 
        new MockHttpResponseGenerator('http://google.com','Hello World');

    Test.startTest();

    Test.setMock(HttpCalloutMock.class, mock);

    Http h = new Http();
    HttpRequest req = new HttpRequest();
    req.setEndpoint('http://google.com');
    req.setMethod('GET');

    // Send the request, and return a response
    HttpResponse res = h.send(req);
    String resp = res.getBody();

    Test.stopTest();
}

It is embarrassing how long I've spent trying to debug this with no progress...

The object in question is a dummy object and not part of any workflows or triggers.

Am I missing something?

Also the test passes fine in a Full Copy Sandbox that was refreshed less than a month ago.

Answer 1

Change API Version to 35. Version 35 doesn't have this issue.

Answer 2

Turns out another reason this might be happening is if you have a workflow that with an Email Alert action. You can easily see if this is happening by searching your debug log for an event of: WF_EMAIL_ALERT.

I had a project where I couldn't seem to test ANY callout, no matter how simple the setup. Turns out the Account had a workflow on it that sent an email alert if a field was blank. Of course my TestUtil method that was instantiating accounts wasn't setting this field.