OCMock and AVCaptureDeviceInput

I'm in the process of updating our test suite from OCMock 2 to OCMock 3 and am running into a few issues. One of the issue is that we're trying to mock AVCaptureDeviceInput.

For one of the test we want to return a mocked instance AVCaptureDeviceInput when a class method is called on AVCaptureDeviceInput.

in our setup method:

 self.mockAVCaptureDeviceInputClass = [OCMockObject mockForClass:[AVCaptureDeviceInput class]];

in our test:

    id deviceInput = [OCMockObject mockForClass: [AVCaptureDeviceInput class]];
    [[[[self.mockAVCaptureDeviceInputClass stub] classMethod] andReturn:deviceInput]
     deviceInputWithDevice:mockDevice error:((NSError __autoreleasing **)[OCMArg setTo:nil])];

The issue seems to be that deviceInput overwrites the self.mockAVCaptureDeviceInputClass so that when the classMethod is stubbed, it does not do anything.

An alternative I tried to work around this was to create a mock for an instance of AVCaptureDeviceInput, but that just hangs:

[OCMockObject partialMockForObject: [AVCaptureDeviceInput new]];

with the following stack trace:

    0x000000010938a219 in _object_set_associative_reference ()
    0x0000000108aed5c3 in OCMSetAssociatedMockForClass at /Users/otusweb/Desktop/dfsa/Pods/OCMock/Source/OCMock/OCMFunctions.m:226
    0x00000001144ecce2 in -[OCClassMockObject prepareClassForClassMethodMocking] at /Users/otusweb/Desktop/dfsa/Pods/OCMock/Source/OCMock/OCClassMockObject.m:89
    0x00000001144ec934 in -[OCClassMockObject initWithClass:] at /Users/otusweb/Desktop/dfsa/Pods/OCMock/Source/OCMock/OCClassMockObject.m:31
    0x00000001144f47f6 in -[OCPartialMockObject initWithObject:] at /Users/otusweb/Desktop/dfsa/Pods/OCMock/Source/OCMock/OCPartialMockObject.m:33
    0x00000001144f1cdd in +[OCMockObject partialMockForObject:] at /Users/otusweb/Desktop/dfsa/Pods/OCMock/Source/OCMock/OCMockObject.m:58
    0x00000001144e9abe in -[dfsaTests testExample] at /Users/otusweb/Desktop/dfsa/dfsaTests/dfsaTests.m:33