bug: incorrect typing for builtin functions whose return type depends on its arguments' types

[tserg]

Version Information

• vyper Version (output of vyper --version): https://github.com/vyperlang/vyper/commit/9e3b9a2b8ae55aa83b5450080f750be15f819de7
• OS: linux
• Python Version (output of python --version): 3.10.4

What's your issue about?

Builtin functions whose return type depends on some of its argument's type can be incorrectly typed resulting in the compiler exiting with a TypeMismatch.

To trigger this behavior, call the builtin function with arguments such that:

1. at least one argument is not constant (as the call would be folded otherwise)
2. get_possible_types_from_node should return multiple potential types for this arguments on which the return type of the builtin function depends.

Affected builtins:

• min and max: a: uint256 = min(1 if True else 2, 1)
• all unsafe builtins: a: uint256 = unsafe_add(1 if True else 2, 1)
• shift (deprecated as of v0.3.8): a: uint256 = shift(-1, 1 if True else 2)
• uint2str: f: String[12] = uint2str(1 if True else 2)

h/t @trocher

How can it be fixed?

Fill this in if you know how to fix it.

[trocher]

Other example:

@external
@payable
def foo():
    x:uint256 = 1
    a:uint256 = min([1,2][x], 1)

 vyper.exceptions.TypeMismatch: Given reference has type int8, expected uint256

(Also for reference still an issue as of 0.3.10)

[charles-cooper]

note: several of these are resolved as of v0.4.0b1 (b53a020c74857de33cf4fd1a6d24a398539758b1) but some still will not compile.