Improve default value for None in text_signature

[messense]

xref #2863

[davidhewitt]

Thanks!

I think there's another test case to consider, which is what happens if the argument is implicitly defaulted to None, as per https://pyo3.rs/v0.18.2/function/signature#trailing-optional-arguments

i.e. this test case:

#[pyfunction]
fn increment(x: u64, amount: Option<u64>) -> u64 {
    x + amount.unwrap_or(1)
}

should have __text_signature__ == (x, amount=None)

[messense]

Thanks for the review, I think I've addressed it now.

[davidhewitt]

Thanks, looks great, sorry I missed your reply earlier!

bors r+

[davidhewitt]

bors r-

[bors]

Canceled.

[davidhewitt]

bors r+

[davidhewitt]

(whoops, looks like bors is fine and I just hadn't noticed another batch is already merging, sorry for the spam 😅)

[bors]

Build succeeded:

• conclusion