Incorrect code collapse while prompting where the error is.

Bug report

Bug description:

Read the following code:

# incorrect_collapse.py
def fib(number: int) -> int:
    assert number > 0
    if number == 1:
        return 1

    return fib(number - 1) + fib(number - 2)  # Notice here


print(fib(2))

There is a mistake in the code above, so if you try to run it, you will get the following traceback:

PC-Killer@ArchLinuxPC ~/p/bugs> python incorrect_collapse.py
Traceback (most recent call last):
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 9, in <module>
    print(fib(2))
          ~~~^^^
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 6, in fib
    return fib(number - 1) + fib(number - 2)  # Notice here
                             ~~~^^^^^^^^^^^^
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 2, in fib
    assert number > 0
           ^^^^^^^^^^
AssertionError

Notice that the error happened while running the code fib(number - 2).
However, if the number is 5, the duplicate code will be automatically collapsed:

# incorrect_collapse.py
def fib(number: int) -> int:
    assert number > 0
    if number == 1:
        return 1

    return fib(number - 1) + fib(number - 2)  # Notice here


print(fib(5))

PC-Killer@ArchLinuxPC ~/p/bugs [1]> python incorrect_collapse.py
Traceback (most recent call last):
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 9, in <module>
    print(fib(5))
          ~~~^^^
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 6, in fib
    return fib(number - 1) + fib(number - 2)  # Notice here
           ~~~^^^^^^^^^^^^
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 6, in fib
    return fib(number - 1) + fib(number - 2)  # Notice here
           ~~~^^^^^^^^^^^^
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 6, in fib
    return fib(number - 1) + fib(number - 2)  # Notice here
           ~~~^^^^^^^^^^^^
  [Previous line repeated 1 more time]
  File "/home/PC-Killer/python_work/bugs/incorrect_collapse.py", line 2, in fib
    assert number > 0
           ^^^^^^^^^^
AssertionError

The error happened in fib(number - 2). However, in the traceback above, I can only suppose the error happened while running fib(number - 1), which increases the time to find where the real bug is.

CPython versions tested on:

3.13, 3.14

Operating systems tested on:

Linux

Linked PRs

• gh-129973

Commencez par reproduire le comportement de fusion du traceback avec les deux exemples de Fibonacci de l’issue sur CPython 3.13 ou 3.14, puis inspectez les points d’entrée du formatage du traceback et de la fusion des frames. Comparez la sortie fusionnée avec le traceback non tronqué et le PR lié gh-129973 ; le travail est terminé lorsque l’expression qui échoue reste identifiable après la fusion des frames répétées.