B028: Allow stacklevel to be explicitly assigned as a positional argu…

…ment (#374)

README.rst

@@ -173,7 +173,7 @@ limitations make it difficult.
 
 **B027**: Empty method in abstract base class, but has no abstract decorator. Consider adding @abstractmethod.
 
-**B028**: No explicit stacklevel keyword argument found. The warn method from the warnings module uses a
+**B028**: No explicit stacklevel argument found. The warn method from the warnings module uses a
 stacklevel of 1 by default. This will only show a stack trace for the line on which the warn method is called.
 It is therefore recommended to use a stacklevel of 2 or greater to provide more information to the user.
 
@@ -325,6 +325,10 @@ MIT
 Change Log
 ----------
 
+Unreleased
+~~~~~~~~~~
+* B028: Allow stacklevel to be explicitly assigned as a positional argument
+
 23.3.23
 ~~~~~~~~~~
 

bugbear.py

@@ -1290,6 +1290,7 @@ def check_for_b028(self, node):
             and isinstance(node.func.value, ast.Name)
             and node.func.value.id == "warnings"
             and not any(kw.arg == "stacklevel" for kw in node.keywords)
+            and len(node.args) < 3
         ):
             self.errors.append(B028(node.lineno, node.col_offset))
 
@@ -1674,7 +1675,7 @@ def visit_Lambda(self, node):
 )
 B028 = Error(
     message=(
-        "B028 No explicit stacklevel keyword argument found. The warn method from the"
+        "B028 No explicit stacklevel argument found. The warn method from the"
         " warnings module uses a stacklevel of 1 by default. This will only show a"
         " stack trace for the line on which the warn method is called."
         " It is therefore recommended to use a stacklevel of 2 or"

tests/b028.py

@@ -5,7 +5,9 @@
 B028 - on lines 8 and 9
 """
 
-warnings.warn(DeprecationWarning("test"))
-warnings.warn(DeprecationWarning("test"), source=None)
-warnings.warn(DeprecationWarning("test"), source=None, stacklevel=2)
-warnings.warn(DeprecationWarning("test"), stacklevel=1)
+warnings.warn("test", DeprecationWarning)
+warnings.warn("test", DeprecationWarning, source=None)
+warnings.warn("test", DeprecationWarning, source=None, stacklevel=2)
+warnings.warn("test", DeprecationWarning, stacklevel=1)
+warnings.warn("test", DeprecationWarning, 1)
+warnings.warn("test", category=DeprecationWarning, stacklevel=1)