utils.py 文件源码

def parse_compare(compare_node):
    assert len(compare_node.ops) == 1, "multiple comparison ops?" + ast.dump(compare_node)
    assert isinstance(compare_node.ops[0], ast.Eq), "comparison should be ==" + \
        ast.dump(compare_node.ops[0])

    lhs = compare_node.left
    rhs = compare_node.comparators[0]
    if isinstance(lhs, ast.Name) and isinstance(rhs, ast.Num):
        var_name = lhs.id
        val = rhs.n
    elif isinstance(rhs, ast.Name) and isinstance(lhs, ast.Num):
        var_name = rhs.id
        val = lhs.n
    elif isinstance(rhs, ast.Name) and isinstance(lhs, ast.Name):
        # try to apply macro
        if is_int_constant(rhs):
            var_name = lhs.id
            val = rhs.id
        elif is_int_constant(lhs):
            var_name = rhs.id
            val = lhs.id
        else:
            assert False, "Unable to apply macro to fix comparator " + ast.dump(compare_node)
    else:
        assert False, "unexpected comparator" + ast.dump(compare_node)
    return var_name, val