Python: How to validate function calls without executing code

Question

I want to validate if python function calls are valid without executing them.

Let's say I have the following code:

def func(a, b):
    print(a, b)

cond = True

if cond:
    func(1, 2)
else:
    func(1)

If cond = True, then everything will run just fine, but if cond = False, then it will fail throwing the following error:

TypeError: func() takes exactly 2 arguments (1 given)

I need to know if all function calls are valid, without having to call any function.

Vinay Sharma · Accepted Answer · 2019-11-19 15:53:47Z

2

Such errors can be checked beforehand using mypy.

Install mypy python3 -m pip install -U mypy.
For checking Python3 code run mypy code.py, and for Python2 run mypy --py2 code.py.
It will throw the following error:

code.py:9: error: Too few arguments for "func"
Found 1 error in 1 file (checked 1 source file)

answered Nov 19, 2019 at 15:53

Vinay Sharma

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