mock: make (mock.Call).Times(int) add expectations for each expected call

[Ullaakut]

Summary

See this playground example that highlights the issue.

The current behavior of Times(int) is that if the expectation of X calls being made is not met, the error message that gets written is The code you are testing needs to make 1 more call(s). which is very confusing, because there might be more than 1 call missing.

For example if you expect 50 calls and that only 5 are made, one would expect the message to be The code you are testing needs to make 45 more call(s)..

This pull request addresses that, by making the Times(int) method append one expectation per call, on the mock.

Changes

• Makes the (mock.Call).Times() method append expectations for each expected call, on the call's parent.
• Updates unit tests accordingly.

Motivation

The current mock error output is misleading.

Related issues

Closes #1383.

[dolmen]

I don't have the knowledge of that code. I would be sure that there is no conflict with the Repeatability property.

I would like the reviews of other people before accepting this change.

[brackendawson]

I do like the idea of adding multiple expectations rather than having to count with mock.Call.Repeatability. Though it would make it even harder to fix .Times(0), which is currently broken too. And it would also break mock.Call.NotBefore.

So we must go with the alternateive and smaller approach, which is to make the error message aware of the Repeatability instance variable.

The approach in this PR is ineffective, it just changes the message to a different fixed number.

[brackendawson]

c is a *Call (pointer to Call), so you actually casue the same call to be added to the Mock's expectations i times.

This is working the same way it used to because we are decrementing c.Repeatabilty on all the expectations at once, since they are the same expectation. The only difference is that the error now says you need to make i more calls, rather than "1" more calls, regarless of how many more you actually need to make.