MemoryError when calling format_field on a Formatter object

[gabe-sherman]

Bug report

Bug description:

The below code results in a 'MemoryError' being raised in the format_field function.

import string
obj = string.Formatter()
ret = obj.format_field("test", "5555555555550555")

Traceback

Traceback (most recent call last):
  File "rep.py", line 4, in <module>
    ret = obj.format_field("test", "5555555555550555")
  File "/usr/lib/python3.10/string.py", line 235, in format_field
    return format(value, format_spec)
MemoryError

CPython versions tested on:

3.10

Operating systems tested on:

Linux

[StanFromIreland]

format_field is a wrapper around format

format("test", "5555555555550555")

Is the core problem. Though IMO it is fine, it is a massive width, and would realistically fail, is there even a point to making it more graceful?

[sergey-miryanov]

What do you expect? Your format string interpreted as a '5555555555550555s' and tried to allocate string with length of 5555555555550555.

[gabe-sherman]

Thank you for the responses. This was found while fuzzing the Python interpreter libraries, and I wasn't sure if it represented a true issue. I will close this issue now, as this represents expected behavior.