nac3-spec/toy-impl/inheritance.py

from helper import *
from type_def import *
import copy

def class_fixup(c: ClassType):
    if c.checking:
        raise CustomError(f'Circular inheritance detected')
    if c.checked:
        return
    c.checking = True
    for p in c.parents:
        class_fixup(p)
        for m in p.methods:
            if m in c.methods:
                old = p.methods[m]
                new = c.methods[m]
                for a, b in zip(old[0], new[0]):
                    if a != b:
                        raise CustomError(f'{m} is different in {c.name} and {p.name}')
                if old[1] != new[1]:
                    # actually, we should check for equality *modulo variable renaming*
                    raise CustomError(f'{m} is different in {c.name} and {p.name}')
            else:
                c.methods[m] = p.methods[m]
        for f in p.fields:
            if f in c.fields:
                if p.fields[f] != c.fields[f]:
                    raise CustomError(f'{f} is different in {c.name} and {p.name}')
            else:
                c.fields[f] = p.fields[f]
    c.checking = False
    c.checked = True