Assume the following function which gets the nth bit from a u8:
fn get_bit(&self, n: u8) -> bool {
if n > 7 {
panic!("Overflow detected while using `get_bit`: Tried to get the {n}th bit.");
}
let result = *self >> n & 1;
if result == 1 {
return true;
} else {
return false;
}
}
The basic (panic-case) test looks like this:
#[test]
#[should_panic]
fn get_bit_panic_ut() {
0b0000_0000.get_bit(8);
}
As you can see this only tests for 8 as input. I want to make sure that this function will panic for any input between 8 and 255. So my naive attempt was:
#[test]
#[should_panic]
fn get_bit_panic_ut() {
for i in 8..=255 {
println!("{i}"); // For demonstration purposes
0b0000_0000.get_bit(i);
}
}
If I run the above with the --nocapture flag, I can see that the test execution stops after 8. So my question is how do I test for all the other cases here?
One option I came across, which might work is the rtest crate. I wonder if rust provides any out of the box mechanics for scenarios like this.
No - but you can easily simulate it:
#[test]
fn get_bit_panic_ut() {
for i in 8..=255 {
println!("{i}"); // For demonstration purposes
assert!(std::panic::catch_unwind(|| 0b0000_0000.get_bit(i)).is_err());
}
}