Testing Question - What do you call this?

[Cirrus]

You are a developing a system which needs to interface to another system. You don't however want to use a test version of the second system, so you build a dummy that has limited functionality sufficient to permit you to do primary system testing.

Now the question is what do you call the dummy system?

I've seen 'double', 'fake', 'mock', 'stub' and others.

I think experts will say there are accepted definitions, only they don't agree amongst themselves what they are. So it's a question of what you personally think is the best term.

The reason I ask this is if you are getting outside parties to develop functions that interface to financial services back office packages or bespoke systems (like insurance or mortgages), it can be very expensive in terms of time, infrastructure, licensing, support etc to create a proper test instance. Worse that that, you potentially expose too much of your proprietary business rules, processes, prices etc to someone who might go sniffing around places of no business to them. If on the other hand you just use very limited calls (which is what 'stub' and 'mock' suggest to me), you unnecessarily miss out on a lot of useful integration coverage.

Do you use this kind of thing?

[stek]

I've only heard 'stub' - i.e. 'stubbing it out', etc....

[MrMarkyMark]

Sounds like the short cut, "saving money" approach that has real potential to go wrong and actually cost a fecking fortune.
Especially as the outside parties, you describe, are likely to be offshore.

[Contreras]

Sounds like you have a <name of system being simulated> 'simulator'. The function availability should be defined.

'stub' can be a substitute code function, typically empty, say for an otherwise incomplete project to build.

'mock' can be for demonstrating look and feel of a product prior to full implementation, say a dummy GUI with no real functionality behind it.

[NotAllThere]

Mock.

[SimonMac]

Mainly stub, sometimes mock

[SimonMac]

Sounds like the short cut, "saving money" approach that has real potential to go wrong and actually cost a fecking fortune.
Especially as the outside parties, you describe, are likely to be offshore.

Not really, you mainly use stubs on dev and sometimes system test, not all interfaces you work with have test environments themselves.

The stub just simulates a happy path call so you can check that was should be returned by the live system is accepted into your new system.

If you have never come across a stub before you are either not a tester, or a crap code monkey

[MrMarkyMark]

FTFY

'mock' can be for demonstrating look and feel of a product purely as an attempt to grab more budget, as the project, in reality, is going really badly. There will be a damp squib of an implementation, prior to the PM moving on. Say a dummy GUI with no real, or attainable, functionality behind it.

[The Spartan]

Mock.

This ^^

[LondonManc]

It's an incomplete test instance. Badge it how you want; you're just rolling a turd in glitter and hoping it shines.