Simplify and optimize interception #523
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By moving the code that finds a setup for an invocation inside the `lock` of the `InterceptorContext`, we can avoid creating a snapshot copy of all setups for each invocation.
Most methods that get invoked on a delegate won't be event accessors. Therefore, checking for each invocation whether it is such a one should take as little time as possible.
Some well-known methods have predefined behavior (`object` methods, `IMocked.Mock` and `IMocked<T>.Mock`, as well as finalizers). Instead of having three interception strategies for these and going through each sequentially, let's just have one dictionary-based one.
Source/Interceptor.cs
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| HandleTracking.Instance, | ||
| InterceptMockPropertyMixin.Instance, | ||
| InterceptObjectMethodsMixin.Instance, | ||
| HandleWellKnownMethods.Instance, |
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Handling finalizers after HandleTracking might in theory be problematic since the objects related to the one being finalized might already be gone. But then, assuming that the underlying proxy library might intercept a finalizer is just as problematic. (DynamicProxy doesn't intercept finalizers, so all logic in Moq that deals with a finalizer call is really just a backup.)
| @@ -261,8 +265,10 @@ public void Verify() | |||
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| private bool TryVerify(out UnmatchedSetups error) | |||
| { | |||
| if (!this.Interceptor.TryVerify(out error)) | |||
| var uninvokedVerifiableSetups = this.Setups.ToArrayLive(setup => setup.IsVerifiable && !setup.Invoked); | |||
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By moving setups from InterceptorContext into Mock, verification is no longer spread across three types (Mock, Interceptor, InterceptorContext) but happens completely within Mock.
| @@ -107,6 +101,8 @@ public override Switches Switches | |||
| set => this.owner.Switches = value; | |||
| } | |||
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| internal override Type TargetType => this.owner.TargetType; | |||
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This is almost identical to MockedType, except for the overrides in AsInterface.
This PR achieves two things:
Makes the whole interception mechanism a little simpler and easier to understand.
InterceptorContextis replaced by dedicated collection properties directly onMock:Mock.Setups,Mock.Invocations, andMock.EventHandlers. These use dedicated collection types who perform the necessary locking (for thread-safety) internally.Applies several optimizations (such as fewer allocations and collection copying) that speed up mock method interception by approx. 30% (though interception is already pretty fast, so this might not be very noticeable).
(There's possibly room for further speed improvements, esp. regarding the
locks inside the collection typesSetupCollection,InvocationCollection,EventHandlerCollection.)