checks.py 文件源码

def _visit_compare(self, left, op, right):
        swap = False
        if not isinstance(left, ast.Attribute):
            left, right = right, left
            swap = True
        if not isinstance(left, ast.Attribute):
            return
        hardcoded_errno = (
            left.attr == 'errno' and
            op in astaux.equality_ops and
            isinstance(right, ast.Num) and
            isinstance(right.n, int) and
            right.n in errno_constants
        )
        if hardcoded_errno:
            yield self.tag(right, '*hardcoded-errno-value', right.n)
        sys_attr_comparison = (
            isinstance(left.value, ast.Name) and
            left.value.id == 'sys'
        )
        if sys_attr_comparison:
            if left.attr == 'version':
                tpl = None
                if isinstance(right, ast.Str):
                    if op in astaux.inequality_ops:
                        try:
                            tpl = sysversion.version_to_tuple(right.s)
                        except (TypeError, ValueError):
                            pass
                    elif swap and (op in astaux.in_ops):
                        if right.s == 'PyPy':
                            tpl = False
                            op = ast.Eq if isinstance(op, ast.In) else ast.NotEq
                            yield self.tag(left, 'sys.version-comparison',
                                format_cmp('platform.python_implementation()', op, repr('PyPy'))
                            )
                if tpl is False:
                    pass
                elif tpl is None:
                    yield self.tag(left, 'sys.version-comparison')
                else:
                    yield self.tag(left, 'sys.version-comparison',
                        format_cmp('sys.version_info', op, tpl, swap=swap)
                    )
            elif left.attr == 'hexversion':
                tpl = None
                if isinstance(right, ast.Num) and (op in astaux.numeric_cmp_ops):
                    try:
                        tpl = sysversion.hexversion_to_tuple(right.n)
                    except (TypeError, ValueError):
                        pass
                if tpl is None:
                    yield self.tag(left, 'sys.hexversion-comparison')
                else:
                    yield self.tag(left, 'sys.hexversion-comparison',
                        format_cmp('sys.version_info', op, tpl, swap=swap)
                    )