如何在 EXPECT_CALL 中使用 testing::_，不包括 2 个值？

Question

I have a method, which inside calls a method which returns bool value - in this question let's name the method:

bool IsFilled(int value)

Now in another method which I am testing this is being called multiple times:

if (IsFilled(0)) 
{
   if (IsFilled(1)){
      ...
   } else {
      ...
   }
}

for (int i = 1; i < range; i++)
{
   if (IsFilled(i)) {
       ...
       if (IsFilled(0)) {
       
       }
   }
}

Now how would one test it correctly with gtest? I am mainly going for coverage and testing branches more than values. As such I was expecting to do something like this:

EXPECT_CALL(adapter, IsFilled(0)).Times(zeroCalls).WillOnce(IndexZeroResults);
EXPECT_CALL(adapter, IsFilled(1)).Times(oneCalls).WillOnce(IndexOneResults);
EXPECT_CALL(adapter, IsFilled(_)).Times(otherCalls).WillOnce(IndexOtherResults);

I need the 0/1 calls separated as then I can test all branches, however, the "_" would duplicate the 0/1 calls as it tests with random values. Is it possible to exclude it?

Answer 1

TL;DR - swap the order of EXPECT_CALL s:

EXPECT_CALL(adapter, IsFilled(_)).Times(otherCalls).WillOnce(IndexOtherResults);
EXPECT_CALL(adapter, IsFilled(1)).Times(oneCalls).WillOnce(IndexOneResults);
EXPECT_CALL(adapter, IsFilled(0)).Times(zeroCalls).WillOnce(IndexZeroResults);

---

This works because of GoogleMock rules for ordering EXCEPT_CALLs . Expectations are always considered in reverse order than they were declared (so last declared expectation is verified first). It is like that to allow you to create general expectations in test fixture and specific expectations in test body.