Add interval option to Simple Button

Author: furbrain

async_button.py

@@ -51,7 +51,9 @@ class SimpleButton:
     task.
     """
 
-    def __init__(self, pin: Pin, value_when_pressed: bool, pull: bool = True):
+    def __init__(
+        self, pin: Pin, value_when_pressed: bool, *, pull: bool = True, interval=0.05
+    ):
         """
 
         :param Pin pin: Pin to wait for
@@ -62,9 +64,14 @@ def __init__(self, pin: Pin, value_when_pressed: bool, pull: bool = True):
           it is ``True``. If an external pull is already provided for the pin, you can set
           pull to ``False``. However, enabling an internal pull when an external one is already
           present is not a problem; it simply uses slightly more current.
+        :param float interval: How long to wait between checks of whether the button has changed.
+          Default is 0.05s (human experience of "instantaneous" is up to 0.1s). This parameter
+          can be set to zero and the button will be checked as often as possible, although other
+          coroutines will still be able to run.
         """
         self.pin: Pin = pin
         self.value_when_pressed = value_when_pressed
+        self.interval = interval
         if pull:
             self.pull = digitalio.Pull.DOWN if value_when_pressed else digitalio.Pull.UP
         else:
@@ -79,7 +86,7 @@ async def pressed(self):
             while True:
                 if counter.count > 0:
                     return
-                await asyncio.sleep(0)
+                await asyncio.sleep(self.interval)
 
     async def released(self):
         """
@@ -90,7 +97,7 @@ async def released(self):
             while True:
                 if counter.count > 0:
                     return
-                await asyncio.sleep(0)
+                await asyncio.sleep(self.interval)
 
 
 class Button:

tests/test_async_simple_button.py

@@ -26,15 +26,14 @@ def setUp(self) -> None:
         self.counter.__enter__.return_value = (
             self.counter
         )  # return self as a context manager
-        type(self.counter).count = PropertyMock(side_effect=[0, 0, 1])
+        type(self.counter).count = PropertyMock(side_effect=[0, 0, 1, 0, 0, 1])
         self.countio.Counter.return_value = self.counter
         self.asyncio = MagicMock()
         self.asyncio.sleep = AsyncMock()
         self.patch_asyncio = patch("async_button.asyncio", self.asyncio)
         self.patch_asyncio.start()
         self.edge_rise = self.countio.Edge.RISE
         self.edge_fall = self.countio.Edge.FALL
-        self.simple_button_class = async_button.SimpleButton
 
     def tearDown(self) -> None:
         self.patch_asyncio.stop()
@@ -49,25 +48,54 @@ async def test_pressed_active_high(self):
         self.assertEqual(self.asyncio.sleep.await_count, 2)
 
     async def test_released_active_high(self):
-        button = self.simple_button_class("P1", True)
+        button = async_button.SimpleButton("P1", True)
         await button.released()
         self.countio.Counter.assert_called_once_with(
             "P1", edge=self.edge_fall, pull=digitalio.Pull.DOWN
         )
         self.assertEqual(self.asyncio.sleep.await_count, 2)
 
     async def test_pressed_active_low(self):
-        button = self.simple_button_class("P1", False)
+        button = async_button.SimpleButton("P1", False)
         await button.pressed()
         self.countio.Counter.assert_called_once_with(
             "P1", edge=self.edge_fall, pull=digitalio.Pull.UP
         )
         self.assertEqual(self.asyncio.sleep.await_count, 2)
 
     async def test_released_active_low(self):
-        button = self.simple_button_class("P1", False)
+        button = async_button.SimpleButton("P1", False)
         await button.released()
         self.countio.Counter.assert_called_once_with(
             "P1", edge=self.edge_rise, pull=digitalio.Pull.UP
         )
         self.assertEqual(self.asyncio.sleep.await_count, 2)
+
+    async def test_pull_false_is_respected(self):
+        button = async_button.SimpleButton("P1", False, pull=False)
+        await button.released()
+        self.countio.Counter.assert_called_once_with(
+            "P1", edge=self.edge_rise, pull=None
+        )
+        self.assertEqual(self.asyncio.sleep.await_count, 2)
+
+    async def test_default_interval(self):
+        button = async_button.SimpleButton("P1", False)
+        await button.pressed()
+        self.asyncio.sleep.assert_awaited_with(0.05)
+        await button.released()
+        self.asyncio.sleep.assert_awaited_with(0.05)
+
+    async def test_interval_zero(self):
+        button = async_button.SimpleButton("P1", False, interval=0)
+        await button.pressed()
+        self.asyncio.sleep.assert_awaited_with(0)
+        await button.released()
+        self.asyncio.sleep.assert_awaited_with(0)
+
+    async def test_other_interval(self):
+        button = async_button.SimpleButton("P1", False, interval=1.25)
+        await button.pressed()
+        self.asyncio.sleep.assert_awaited_with(1.25)
+        await button.released()
+        self.asyncio.sleep.assert_awaited_with(1.25)