slice() with String[N] fails if the sliced region exceeds the underlying string’s actual length #4685
Description
Version Information
- vyper Version (output of
vyper --version): 0.4.1 - OS: linux
- Python Version (output of
python --version): 3.12
What's your issue about?
Using slice with a String[N] variable uses the string's actual length rather than the specified N.
For instance:
@view
@external
def foo() -> String[5]:
id_label: String[78] = uint2str(123)
short_id: String[5] = slice(id_label, 0, 5)
return short_id
Will revert, but:
@view
@external
def foo() -> String[5]:
id_label: String[78] = uint2str(123456)
short_id: String[5] = slice(id_label, 0, 5)
return short_id
will work fine.
Both use String[78] for id_label. The only difference is the runtime length: "123" vs "123456".
I'd expect in both cases slice(id_label, 0, 5) should succeed.
You could check the length and use convert but it's not great UX