Inferred types should be backtracked up to method definition

[sk-]

When inferring types within a function, those should be used to compute the type signature of the function. For example

<?php

function foo($foo) {
    return $foo + 2;
}

gives the error

Notice: Type mismatch: expected: Numeric, found: Any
return $foo + 2;

However, the type inferencer should detect that in this case foo receives a numeric argument and enforce it later.

[colder]

Hi,

you are right, in this case we could do backward analysis to come up with best-constraints for arguments. That would resolve such cases. It is however non trivial to do this inter-procedurally, (with e.g. recursive functions).

The only way currently is to solve this by annotating the function that it takes a numeric argument.