Activity

1. KotlinIsland

   added

   bugmypy got something wrongmypy got something wrong

   on Jul 2, 2024
2. hauntsaninja

   added

   priority-2-low

   topic-tests

   on Jul 2, 2024
3. KotlinIsland

   changed the title [-](🐞) `--update-data` remove escapes[/-] [+](🐞) `--update-data` removes escapes[/+] on Jul 3, 2024
4. wyattscarpenter commented on Sep 24, 2025

   

   wyattscarpenter

   on Sep 24, 2025

   Contributor

   More actions

   This is especially annoying, I found out in #19923, when you're trying to make a

   [file foo.ini]
   \[mypy]
   whatever=True
   

   section. --update-data keeps ruining the dang config.

   In case it helps diagnose the problems: I also discovered in https://github.com/python/mypy/pull/19904/files#diff-a359250205cd7c3fa369eb8557c577b353446e840f18a9fe46844232ab3c320fL1018 that it does the same thing with

   #type: ignore[whatever] \
   # E: some message
   

   transforming that into

   #type: ignore[whatever] # E: some message
   

   But luckily that doesn't matter.
5. wyattscarpenter commented on Sep 27, 2025

   

   wyattscarpenter

   on Sep 27, 2025

   Contributor

   More actions

   This bug is probably the result of this line interpreting \[ bits from parse_test_data in mypy/test/data.py, which is then used by
   _iter_fixes in mypy/test/update_data.py. Presumably these two pieces of logic are working at cross-purposes; One needs to interpret the test case to something Python can execute, and one needs to reproduce it exactly... If I'm right, the simple fix is simply escaping the bracket again as we output to fix lines. If I'm right, this also implies that test-style comments will disappear, which I guess we just haven't tested?