Handle multiple receiver decorators in receiver-decorator (#2858)

crates/ruff/resources/test/fixtures/flake8_django/DJ013.py

@@ -15,3 +15,23 @@ def correct_pre_save_handler():
 @receiver(pre_save, sender=MyModel)
 def incorrect_pre_save_handler():
     pass
+
+
+@receiver(pre_save, sender=MyModel)
+@receiver(pre_save, sender=MyModel)
+@test_decorator
+def correct_multiple():
+    pass
+
+
+@receiver(pre_save, sender=MyModel)
+@receiver(pre_save, sender=MyModel)
+def correct_multiple():
+    pass
+
+
+@receiver(pre_save, sender=MyModel)
+@test_decorator
+@receiver(pre_save, sender=MyModel)
+def incorrect_multiple():
+    pass

crates/ruff/src/checkers/ast.rs

@@ -465,13 +465,11 @@ where
                 ..
             } => {
                 if self.settings.rules.enabled(&Rule::ReceiverDecoratorChecker) {
-                    if let Some(diagnostic) =
-                        flake8_django::rules::receiver_decorator_checker(decorator_list, |expr| {
-                            self.resolve_call_path(expr)
-                        })
-                    {
-                        self.diagnostics.push(diagnostic);
-                    }
+                    self.diagnostics
+                        .extend(flake8_django::rules::receiver_decorator_checker(
+                            decorator_list,
+                            |expr| self.resolve_call_path(expr),
+                        ));
                 }
                 if self.settings.rules.enabled(&Rule::AmbiguousFunctionName) {
                     if let Some(diagnostic) =

crates/ruff/src/rules/flake8_django/rules/receiver_decorator_checker.rs

@@ -51,25 +51,30 @@ impl Violation for ReceiverDecoratorChecker {
 pub fn receiver_decorator_checker<'a, F>(
     decorator_list: &'a [Expr],
     resolve_call_path: F,
-) -> Option<Diagnostic>
+) -> Vec<Diagnostic>
 where
     F: Fn(&'a Expr) -> Option<CallPath<'a>>,
 {
+    let mut diagnostics = vec![];
+    let mut seen_receiver = false;
     for (i, decorator) in decorator_list.iter().enumerate() {
-        if i == 0 {
-            continue;
-        }
-        let ExprKind::Call{ func, ..} = &decorator.node else {
-            continue;
+        let is_receiver = match &decorator.node {
+            ExprKind::Call { func, .. } => resolve_call_path(func).map_or(false, |call_path| {
+                call_path.as_slice() == ["django", "dispatch", "receiver"]
+            }),
+            _ => false,
         };
-        if resolve_call_path(func).map_or(false, |call_path| {
-            call_path.as_slice() == ["django", "dispatch", "receiver"]
-        }) {
-            return Some(Diagnostic::new(
+        if i > 0 && is_receiver && !seen_receiver {
+            diagnostics.push(Diagnostic::new(
                 ReceiverDecoratorChecker,
                 Range::from_located(decorator),
             ));
         }
+        if !is_receiver && seen_receiver {
+            seen_receiver = false;
+        } else if is_receiver {
+            seen_receiver = true;
+        }
     }
-    None
+    diagnostics
 }

crates/ruff/src/rules/flake8_django/snapshots/ruff__rules__flake8_django__tests__DJ013_DJ013.py.snap

@@ -12,4 +12,14 @@ expression: diagnostics
     column: 35
   fix: ~
   parent: ~
+- kind:
+    ReceiverDecoratorChecker: ~
+  location:
+    row: 35
+    column: 1
+  end_location:
+    row: 35
+    column: 35
+  fix: ~
+  parent: ~