Avoid no-handlers false positives (#3702)

examples/playbooks/no_handler_pass.yml

@@ -82,3 +82,14 @@
       ansible.builtin.debug:
         msg: why isn't this a handler
       when: result | changed
+
+  handlers:
+    # If this task would have being under 'tasks:' it should have triggered
+    # the rule, but under 'handlers:' it should not.
+    - name: Reproduce bug 3646
+      loop: "{{ _something_done.results }}"
+      loop_control:
+        label: "{{ item.item.name }}"
+      when: item.changed
+      ansible.builtin.debug:
+        msg: "{{ item.item.name }} changed"

src/ansiblelint/rules/no_handler.py

@@ -69,18 +69,18 @@ def matchtask(
         task: Task,
         file: Lintable | None = None,
     ) -> bool | str:
-        if task["__ansible_action_type__"] != "task":
+        if task["__ansible_action_type__"] != "task" or task.is_handler():
             return False
 
         when = task.get("when")
+        result = False
 
         if isinstance(when, list):
-            if len(when) > 1:
-                return False
-            return _changed_in_when(when[0])
-        if isinstance(when, str):
-            return _changed_in_when(when)
-        return False
+            if len(when) <= 1:
+                result = _changed_in_when(when[0])
+        elif isinstance(when, str):
+            result = _changed_in_when(when)
+        return result
 
 
 if "pytest" in sys.modules:

src/ansiblelint/utils.py

@@ -753,6 +753,10 @@ def skip_tags(self) -> list[str]:
         skip_tags: list[str] = self.raw_task.get(SKIPPED_RULES_KEY, [])
         return skip_tags
 
+    def is_handler(self) -> bool:
+        """Return true for tasks that are handlers."""
+        return ".handlers[" in self.position
+
     def __repr__(self) -> str:
         """Return a string representation of the task."""
         return f"Task('{self.name}' [{self.position}])"