[Python] How to use Python type hinting to mock values and perform static analysis when a...

I’m working with some external Python code that I cannot modify. This code interacts with my own code, and while I can't add type annotations or assert statements to the external code, I can mock certain pieces for static analysis.

The goal is to mock a class that has a value bound at runtime (i.e., ival) and perform static analysis to ensure that values remain within a defined range during static analysis (e.g., 1 ≤ ival ≤ 100).

At runtime, however, the value of ival can exceed this bound. For example, I want to flag certain conditions where the value of ival is used in comparisons that should be unreachable (such as comparing against a number larger than the max value).

Here's a simplified version of the code:

# Pseudo type code
BoundedInt1To100 = Int[1-100]

class MockMyClass:
def __init__(self, min_val: int, max_val: int, value: int):
self.min = min_val
self.max = max_val
self._value = value

@property
def ival(self) -> BoundedInt0To100:
return self._value

mock100 = MockMyClass(1, 100, 50)

# This comparison should be flagged as unreachable during static analysis
if mock100.ival > 220:
print("This should be flagged as unreachable since 220 exceeds max value of 100.")


I’ve explored the typing module, but I didn’t find a direct way to enforce value ranges at static analysis time while allowing runtime flexibility.

I’ve tried using custom classes for type hints, but I can’t find an elegant solution to mock the runtime behavior while ensuring correct static analysis.

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