Support expression-based mock creation for constructor calls that takes parameters

[frblondin]

Existing mock creation overloads for constructors that take parameters has some limitations:

• Compiler can't check whether the constructor actually exists. Issues/regressions are detected during runtime rather than leveraging code editor capacity
• Editor features such as Finding references... to a constructor is missing calls to the constructor made by these mocks
• When refactoring code, we end up missing those references... and introduce errors (back to first bullet point)

I think it would be relatively simple to add new overloads to Mock and MockRepository that take an Expression<Func<T>> as a parameter. Something like:

var mock1 = new Mock<SomeType>(() => new SomeType("foo"));
var mock2 = repository.Create(() => new SomeType("foo"));

If you think it's a good idea I could submit a PR. What do you think?

[stakx]

Hi @frblondin, that idea would be in line with one of Moq's declared goals (promoting correct code through static typing), so I don't have any objection to adding the new overloads that you're suggesting. Feel free to submit a PR.

add new overloads to Mock and MockRepository that take an Expression<Func<T>> as a parameter

• The overload should go in Mock<T>, not in Mock (as I'm sure you realise).

• There has to be a possibility to optionally specify a MockBehavior; either via an optional parameter, or an additional overload. Ideally, the parameter order will be based on that of existing constructors / methods.

[stakx]

(@frblondin, I have assigned this issue to you and a future version milestone, just to help me track this issue more easily. But don't let that put any pressure on you.)

[frblondin]

Just submitted a PR: #888!

[stakx]

Implemented in #888.