Add types to signals.py (#1344)

Signed-off-by: Michael Carlstrom <[email protected]>

rclpy/rclpy/impl/_rclpy_pybind11.pyi

@@ -14,7 +14,7 @@
 
 from __future__ import annotations
 
-from enum import IntEnum
+from enum import Enum, IntEnum
 from types import TracebackType
 from typing import Any, Generic, Literal, overload, Sequence, TypedDict
 
@@ -333,3 +333,31 @@ class WaitSet(Destroyable):
 
     def wait(self, timeout: int) -> None:
         """Wait until timeout is reached or event happened."""
+
+
+class SignalHandlerOptions(Enum):
+    _value_: int
+    NO = ...
+    SigInt = ...
+    SigTerm = ...
+    All = ...
+
+
+def register_sigint_guard_condition(guard_condition: GuardCondition) -> None:
+    """Register a guard condition to be called on SIGINT."""
+
+
+def unregister_sigint_guard_condition(guard_condition: GuardCondition) -> None:
+    """Stop triggering a guard condition when SIGINT occurs."""
+
+
+def install_signal_handlers(options: SignalHandlerOptions) -> None:
+    """Install rclpy signal handlers."""
+
+
+def get_current_signal_handlers_options() -> SignalHandlerOptions:
+    """Get currently installed signal handler options."""
+
+
+def uninstall_signal_handlers() -> None:
+    """Uninstall rclpy signal handlers."""

rclpy/rclpy/signals.py

@@ -11,26 +11,31 @@
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
 # limitations under the License.
+from typing import Optional, TYPE_CHECKING
 
 from rclpy.exceptions import InvalidHandle
 from rclpy.guard_condition import GuardCondition
 from rclpy.impl.implementation_singleton import rclpy_implementation as _rclpy
 
+if TYPE_CHECKING:
+    from typing import TypeAlias
+
+    from rclpy.context import Context
 
 # re-export SignalHandlerOptions enum
-SignalHandlerOptions = _rclpy.SignalHandlerOptions
+SignalHandlerOptions: 'TypeAlias' = _rclpy.SignalHandlerOptions
 
 
-def install_signal_handlers(options: SignalHandlerOptions = SignalHandlerOptions.ALL):
+def install_signal_handlers(options: SignalHandlerOptions = SignalHandlerOptions.ALL) -> None:
     """
     Install rclpy signal handlers.
 
     :param options: Indicate if to install sigint, sigterm, both or no signal handler.
     """
-    return _rclpy.install_signal_handlers(options)
+    _rclpy.install_signal_handlers(options)
 
 
-def get_current_signal_handlers_options():
+def get_current_signal_handlers_options() -> SignalHandlerOptions:
     """
     Get current signal handler options.
 
@@ -39,19 +44,19 @@ def get_current_signal_handlers_options():
     return _rclpy.get_current_signal_handlers_options()
 
 
-def uninstall_signal_handlers():
+def uninstall_signal_handlers() -> None:
     """Uninstall the rclpy signal handlers."""
     _rclpy.uninstall_signal_handlers()
 
 
 class SignalHandlerGuardCondition(GuardCondition):
 
-    def __init__(self, context=None):
+    def __init__(self, context: 'Optional[Context]' = None) -> None:
         super().__init__(callback=None, callback_group=None, context=context)
         with self.handle:
             _rclpy.register_sigint_guard_condition(self.handle)
 
-    def __del__(self):
+    def __del__(self) -> None:
         try:
             self.destroy()
         except InvalidHandle:
@@ -61,7 +66,7 @@ def __del__(self):
             # Guard condition was not registered
             pass
 
-    def destroy(self):
+    def destroy(self) -> None:
         with self.handle:
             _rclpy.unregister_sigint_guard_condition(self.handle)
         super().destroy()