How to use matcher to see if set contains or map containsKey or map (for key) has value?

[cropredyHelix]

Looking through the examples in fflib_Match.cls and fflib_ApexMocksTest.cls I'm not seeing any way to

• see if a set contains an entry
• see if a map contains a key
• see if a map for key k, has value v

My example is testing a VF controller that calls a FooService.doBar(..) Hence, mocking a service FooServiceImpl, method doBar(map<ID,Foo.CustomType>)

I tried this (match on entire map)

// preamble to set up mocks and inject not shown ; it works fine
((FooServiceImpl) mocks.verify(mockFooSvc,1))
  .doBar(new map<ID,Foo.CustomType> {someId => new Foo.CustomType(arg1, arg2)});

but even though doBar is called with the map someId => new Foo.CustomType(arg1, arg2) (verified using debug), the verify method in ApexMocks comes back with

Expected : 1, Actual: 0 -- Wanted but not invoked: FooServiceImpl__sfdc_ApexStub.doBar(Map<Id,Foo.CustomType>)

So, bottom line - would be nice to see how to use matchers on sets (specific entry) and maps (entire map, hasKey, hasValueForKey, etc.) - especially without having to resort to custom matchers.

[cropredyHelix]

After some inspired searching on frup42 blog, I now see how to use fflib_ArgumentCaptor to solve the above on verifying maps. Still seems as if there should be enhancement possibilities for more matchers on fflib_Match to deal with sets.

[dfruddffdc]

Another Apex quirk... This compiles fine:

List<Account> records = new List<Account>{};
List<Object> castUp = (List<Object>)records;
List<Account> castDown = (List<Account>)castUp;

But this doesn't compile, because: Incompatible types since an instance of Set is never an instance of Set