N806, N815, and N816 ignore case patterns #16502
Description
Summary
non-lowercase-variable-in-function (N806), mixed-case-variable-in-class-scope (N815), and mixed-case-variable-in-global-scope (N816) have false negatives for variables assigned in case patterns. Each of the following examples includes tP as a true positive to show that the rule is running plus one or two false negatives.
N806:
$ cat >n806.py <<'# EOF'
def f():
tP = 0
match tP:
case fN: ...
# EOF
$ ruff --isolated check --output-format concise --select N806 n806.py
n806.py:2:5: N806 Variable `tP` in function should be lowercase
Found 1 error.N815:
$ cat >n815.py <<'# EOF'
class C:
tP = 0
match tP:
case int(fN): ...
# EOF
$ ruff --isolated check --output-format concise --select N815 n815.py
n815.py:2:5: N815 Variable `tP` in class scope should not be mixedCase
Found 1 error.N816:
$ cat >n816.py <<'# EOF'
tP = 0
match tP:
case fN1 as fN2: ...
# EOF
$ ruff --isolated check --output-format concise --select N816 n816.py
n816.py:1:1: N816 Variable `tP` in global scope should not be mixedCase
Found 1 error.Version
ruff 0.9.9 (091d0af 2025-02-28)