Assert a function output is not equal to an expression.
Pseudocode: function(a) ≠ b
use assertables::*; let a: i8 = 1; let b: i8 = -2; assert_fn_ne_x!(i8::abs, a, b);
assert_fn_ne_x
assert_fn_ne_x_as_result
debug_assert_fn_ne_x