Traceback Shows Too Much Info For Class Definition Exception

Bug report

Bug description:

Given the following:

class Meta(type):
    def __prepare__(cls, *args, **kwargs):
        raise Exception

class Spam(metaclass=Meta):
    a = 1
    b = 2
    c = 3
    d = 4
    e = 5
    f = 6

I get:

Traceback (most recent call last):
  File "<python-input-10>", line 1, in <module>
    class Spam(metaclass=Meta):
    ...<5 lines>...
        f = 6
  File "<python-input-9>", line 3, in __prepare__
    raise Exception

I would expect this to only show the compound statement's "header":

Traceback (most recent call last):
  File "<python-input-10>", line 1, in <module>
    class Spam(metaclass=Meta):
  File "<python-input-9>", line 3, in __prepare__
    raise Exception

CC @iritkatriel

CPython versions tested on:

CPython main branch

Operating systems tested on:

No response

首先，使用 issue 中的 class 和 metaclass 範例，在 CPython 的 main 分支上重現 traceback。追蹤直譯器如何格式化 class 定義的原始碼範圍，並尋找涵蓋複合陳述式的現有 traceback 測試。完成的標準是：在 prepare 例外之前，traceback 只顯示 class 標頭。