Allow Boolean positionals in setters (#9429)

## Summary

Ignores Boolean trap enforcement for methods that appear to be setters
(as in the Qt and pygame APIs).

Closes https://github.com/astral-sh/ruff/issues/9287.
Closes https://github.com/astral-sh/ruff/issues/8923.

crates/ruff_linter/resources/test/fixtures/flake8_boolean_trap/FBT.py

@@ -71,6 +71,8 @@ foo.is_(True)
 bar.is_not(False)
 next(iter([]), False)
 sa.func.coalesce(tbl.c.valid, False)
+setVisible(True)
+set_visible(True)
 
 
 class Registry:
@@ -114,3 +116,6 @@ from typing import override
 @override
 def func(x: bool):
     pass
+
+
+settings(True)

crates/ruff_linter/src/checkers/ast/analyze/expression.rs

@@ -724,7 +724,7 @@ pub(crate) fn expression(expr: &Expr, checker: &mut Checker) {
                 );
             }
             if checker.enabled(Rule::BooleanPositionalValueInCall) {
-                flake8_boolean_trap::rules::boolean_positional_value_in_call(checker, args, func);
+                flake8_boolean_trap::rules::boolean_positional_value_in_call(checker, call);
             }
             if checker.enabled(Rule::Debugger) {
                 flake8_debugger::rules::debugger_call(checker, expr, func);

crates/ruff_linter/src/rules/flake8_boolean_trap/helpers.rs

@@ -51,13 +51,29 @@ pub(super) fn is_allowed_func_def(name: &str) -> bool {
 /// Returns `true` if an argument is allowed to use a boolean trap. To return
 /// `true`, the function name must be explicitly allowed, and the argument must
 /// be either the first or second argument in the call.
-pub(super) fn allow_boolean_trap(func: &Expr) -> bool {
+pub(super) fn allow_boolean_trap(call: &ast::ExprCall) -> bool {
-    if let Expr::Attribute(ast::ExprAttribute { attr, .. }) = func {
+    let func_name = match call.func.as_ref() {
-        return is_allowed_func_call(attr);
+        Expr::Attribute(ast::ExprAttribute { attr, .. }) => attr.as_str(),
+        Expr::Name(ast::ExprName { id, .. }) => id.as_str(),
+        _ => return false,
+    };
+
+    // If the function name is explicitly allowed, then the boolean trap is
+    // allowed.
+    if is_allowed_func_call(func_name) {
+        return true;
     }
 
-    if let Expr::Name(ast::ExprName { id, .. }) = func {
+    // If the function appears to be a setter (e.g., `set_visible` or `setVisible`), then the
-        return is_allowed_func_call(id);
+    // boolean trap is allowed. We want to avoid raising a violation for cases in which the argument
+    // is positional-only and third-party, and this tends to be the case for setters.
+    if call.arguments.args.len() == 1 {
+        if func_name
+            .strip_prefix("set")
+            .is_some_and(|suffix| suffix.starts_with(|c: char| c == '_' || c.is_ascii_uppercase()))
+        {
+            return true;
+        }
     }
 
     false

crates/ruff_linter/src/rules/flake8_boolean_trap/rules/boolean_positional_value_in_call.rs

@@ -1,6 +1,6 @@
 use ruff_diagnostics::{Diagnostic, Violation};
 use ruff_macros::{derive_message_formats, violation};
-use ruff_python_ast::Expr;
+use ruff_python_ast as ast;
 use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
@@ -45,11 +45,16 @@ impl Violation for BooleanPositionalValueInCall {
     }
 }
 
-pub(crate) fn boolean_positional_value_in_call(checker: &mut Checker, args: &[Expr], func: &Expr) {
+pub(crate) fn boolean_positional_value_in_call(checker: &mut Checker, call: &ast::ExprCall) {
-    if allow_boolean_trap(func) {
+    if allow_boolean_trap(call) {
         return;
     }
-    for arg in args.iter().filter(|arg| arg.is_boolean_literal_expr()) {
+    for arg in call
+        .arguments
+        .args
+        .iter()
+        .filter(|arg| arg.is_boolean_literal_expr())
+    {
         checker
             .diagnostics
             .push(Diagnostic::new(BooleanPositionalValueInCall, arg.range()));

crates/ruff_linter/src/rules/flake8_boolean_trap/snapshots/ruff_linter__rules__flake8_boolean_trap__tests__FBT001_FBT.py.snap

@@ -81,12 +81,12 @@ FBT.py:19:5: FBT001 Boolean-typed positional argument in function definition
 21 |     kwonly_nonvalued_nohint,
    |
 
-FBT.py:89:19: FBT001 Boolean-typed positional argument in function definition
+FBT.py:91:19: FBT001 Boolean-typed positional argument in function definition
    |
-88 |     # FBT001: Boolean positional arg in function definition
+90 |     # FBT001: Boolean positional arg in function definition
-89 |     def foo(self, value: bool) -> None:
+91 |     def foo(self, value: bool) -> None:
    |                   ^^^^^ FBT001
-90 |         pass
+92 |         pass
    |
 
 

crates/ruff_linter/src/rules/flake8_boolean_trap/snapshots/ruff_linter__rules__flake8_boolean_trap__tests__FBT003_FBT.py.snap

@@ -28,14 +28,10 @@ FBT.py:57:17: FBT003 Boolean positional value in function call
 59 | mylist.index(True)
    |
 
-FBT.py:69:38: FBT003 Boolean positional value in function call
+FBT.py:121:10: FBT003 Boolean positional value in function call
-   |
+    |
-67 | os.set_blocking(0, False)
+121 | settings(True)
-68 | g_action.set_enabled(True)
+    |          ^^^^ FBT003
-69 | settings.set_enable_developer_extras(True)
+    |
-   |                                      ^^^^ FBT003
-70 | foo.is_(True)
-71 | bar.is_not(False)
-   |
 
 

crates/ruff_linter/src/rules/flake8_boolean_trap/snapshots/ruff_linter__rules__flake8_boolean_trap__tests__preview__FBT001_FBT.py.snap

@@ -81,26 +81,26 @@ FBT.py:19:5: FBT001 Boolean-typed positional argument in function definition
 21 |     kwonly_nonvalued_nohint,
    |
 
-FBT.py:89:19: FBT001 Boolean-typed positional argument in function definition
+FBT.py:91:19: FBT001 Boolean-typed positional argument in function definition
    |
-88 |     # FBT001: Boolean positional arg in function definition
+90 |     # FBT001: Boolean positional arg in function definition
-89 |     def foo(self, value: bool) -> None:
+91 |     def foo(self, value: bool) -> None:
    |                   ^^^^^ FBT001
-90 |         pass
+92 |         pass
    |
 
-FBT.py:99:10: FBT001 Boolean-typed positional argument in function definition
+FBT.py:101:10: FBT001 Boolean-typed positional argument in function definition
     |
- 99 | def func(x: Union[list, Optional[int | str | float | bool]]):
+101 | def func(x: Union[list, Optional[int | str | float | bool]]):
     |          ^ FBT001
-100 |     pass
+102 |     pass
     |
 
-FBT.py:103:10: FBT001 Boolean-typed positional argument in function definition
+FBT.py:105:10: FBT001 Boolean-typed positional argument in function definition
     |
-103 | def func(x: bool | str):
+105 | def func(x: bool | str):
     |          ^ FBT001
-104 |     pass
+106 |     pass
     |