Is there an expectation for a float value not being equal to the second value?
E.g the opposite of EXPECT_FLOAT_EQ(val1,val2)
I don't think GTest has this functionality, they explain in their documentation
Some floating-point operations are useful, but not that often used. In order to avoid an explosion of new macros, we provide them as predicate-format functions that can be used in predicate assertion macros (e.g. EXPECT_PRED_FORMAT2, etc).
You can define a predicate, as suggested by @idclev 463035818, and pass it into the EXPECT_PRED_FORMAT2(pred, val1, val2). The predicate must conform to the signature:
testing::AssertionResult pred(const char* expr1, const char* expr2,
double val1, double val2);
Where expr1 & expr2 are the string representation of the float arguments that will be used in the assertion messages.