`help` CLI shows a traceback when import failed

[Eclips4]

Currently, help will show a traceback when we type name of something which doesn't exist:

help> 123
Traceback (most recent call last):
 File "<stdin>", line 1, in <module>
 File "<frozen _sitebuiltins>", line 103, in __call__
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 2004, in __call__
 self.interact()
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 2031, in interact
 self.help(request)
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 2057, in help
 elif request: doc(request, 'Help on %s:', output=self._output)
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 1781, in doc
 pager(render_doc(thing, title, forceload))
 ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 1755, in render_doc
 object, name = resolve(thing, forceload)
 ^^^^^^^^^^^^^^^^^^^^^^^^^
 File "C:\Users\KIRILL-1\CLionProjects\cpython\Lib\pydoc.py", line 1741, in resolve
 raise ImportError('''\
ImportError: No Python documentation found for '123'.
Use help() to get the interactive help utility.
Use help(str) for help on the str class.
>>>

I think, this shouldn't be shown.
Is there any reason for this?
Can we show something like
No python documentation found for '123'.?

Reproducible on current main.

Linked PRs

• gh-102541: Hide traceback in help prompt #102614
• [3.12] gh-102541: Hide traceback in help prompt (gh-102614) #105778
• [3.11] gh-102541: Hide traceback in help prompt (gh-102614). #105830
• gh-102541: Fix Helper.help("mod") for non-existent mod #105934
• [3.12] gh-102541: Fix Helper.help("mod") for non-existent mod (GH-105934) #106322
• [3.11] gh-102541: Fix Helper.help("mod") for non-existent mod (GH-105934) #106323
• gh-102541: Add test case for help() for non_existent_module #106340
• [3.12] gh-102541: Add test case for help() for non_existent_module (GH-106340) #106639
• [3.11] gh-102541: Add test case for help() for non_existent_module (GH-106340) #106640

[terryjreedy]

I verified above in 3.11.2 and 3.12.0a6. 3.10.10 is better -- Gives import error message without traceback. But even better would be to give error message without ImportError and return to help> prompt. This should possibly be a separate PR as there might be more discussion that change. (It is possible that 3.11 change is intentional -- this should be checked.)

[Eclips4]

How I understand, it's introduced in #89130.

[Eclips4]

Yeah, i found right way to fix it. I I have slightly changed signature of some functions, which now have argument is_cli (set default to False).
That's doesn't break compatibility with issue which i mentioned above.
Currenly, in help prompt errors looks like that:

help> abd
No Python documentation found for 'abd'.
Use help() to get the interactive help utility.
Use help(str) for help on the str class.

help>

@terryjreedy What you think about this?
BTW, all tests are passed.
I think, error message we should change, any ideas? (this will make us to change some lines in test_pydoc, but it's not hard)

[Eclips4]

@terryjreedy
I think there's no need to backport it to 3.10 branch. I cannot reproduce it there

[terryjreedy]

In closed duplicate #105702, I noted that there was no bug in latest release of 3.8, 3.9, or 3.10. Patch should restore previous behavior, shown on that issue, which is same as shown above. I just installed 32-bit 3.11.0 and it does have the bug. Will look at PR.

[Eclips4]

In closed duplicate #105702, I noted that there was no bug in latest release of 3.8, 3.9, or 3.10. Patch should restore previous behavior, shown on that issue, which is same as shown above. I just installed 32-bit 3.11.0 and it does have the bug. Will look at PR.

Yeah, so, please, delete label 3.10 on this issue, and add 3.13 label, this still reproducible on current main