compile raises SyntaxError with undocumented lineno attribute None

[fweimer]

BPO	44409
Nosy	@lysnikolaou, @pablogsal, @miss-islington
PRs	bpo-44409: Fix error location in tokenizer errors that happen during initialization #26712 [3.10] bpo-44409: Fix error location in tokenizer errors that happen during initialization (GH-26712) #26722 [3.9] bpo-44409: Fix error location in tokenizer errors that happen during initialization (GH-26712). #26723

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2021-06-14.17:27:22.615>
created_at = <Date 2021-06-13.11:25:16.043>
labels = ['interpreter-core', 'type-bug', '3.9']
title = 'compile raises SyntaxError with undocumented lineno attribute None'
updated_at = <Date 2021-06-14.17:27:22.614>
user = 'https://bugs.python.org/fweimer'

bugs.python.org fields:

activity = <Date 2021-06-14.17:27:22.614>
actor = 'pablogsal'
assignee = 'none'
closed = True
closed_date = <Date 2021-06-14.17:27:22.615>
closer = 'pablogsal'
components = ['Parser']
creation = <Date 2021-06-13.11:25:16.043>
creator = 'fweimer'
dependencies = []
files = []
hgrepos = []
issue_num = 44409
keywords = ['patch', '3.9regression', '3.10regression']
message_count = 5.0
messages = ['395740', '395763', '395778', '395811', '395814', '395815']
nosy_count = 4.0
nosy_names = ['fweimer', 'lys.nikolaou', 'pablogsal', 'miss-islington']
pr_nums = ['26712', '26722', '26723']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'behavior'
url = 'https://bugs.python.org/issue44409'
versions = ['Python 3.9']

[fweimer]

This example results in an undocumented value None for the lineno attribute:

source = b"\xef\xbb\xbf#coding: utf8\nprint('\xe6\x88\x91')\n"

try:
    compile(source, filename="example.py", mode="exec")
except SyntaxError as e:
    print(str(e))
    print(type(e.lineno))

Output:

encoding problem: utf8 with BOM
<class 'NoneType'>

Seen with python3-3.9.5-2.fc33.x86_64.

python3-3.8.10-1.fc32.x86_64 used a lineno value of 0 (type int).

[pablogsal]

Well, in both cases this means that the line number is not available. I think None is a bit cleaner in this regard.

[fweimer]

I suppose changing the documentation to mention None would be possible as well, but restoring the old behavior works for me too. Thanks.

[pablogsal]

New changeset 507ed6f by Pablo Galindo in branch 'main':
bpo-44409: Fix error location in tokenizer errors that happen during initialization (GH-26712)
507ed6f

[miss-islington]

New changeset 133cddf by Miss Islington (bot) in branch '3.10':
bpo-44409: Fix error location in tokenizer errors that happen during initialization (GH-26712)
133cddf

[pablogsal]

New changeset 0d0a9ea by Pablo Galindo in branch '3.9':
[3.9] bpo-44409: Fix error location in tokenizer errors that happen during initialization (GH-26712). (GH-26723)
0d0a9ea