added typehints to midimessage and init

adafruit_midi/__init__.py

@@ -25,6 +25,10 @@
   https://github.com/adafruit/circuitpython/releases
 
 """
+try:
+    from typing import Union, Tuple, Any, List, Optional, Dict
+except ImportError:
+    pass
 
 from .midi_message import MIDIMessage
 
@@ -54,13 +58,13 @@ class MIDI:
 
     def __init__(
         self,
-        midi_in=None,
-        midi_out=None,
+        midi_in: Optional[Any] = None,
+        midi_out: Optional[Any] = None,
         *,
-        in_channel=None,
-        out_channel=0,
-        in_buf_size=30,
-        debug=False
+        in_channel: Optional[Union[int, Tuple[int, ...]]] = None,
+        out_channel: int = 0,
+        in_buf_size: int = 30,
+        debug: bool = False
     ):
         if midi_in is None and midi_out is None:
             raise ValueError("No midi_in or midi_out provided")
@@ -78,7 +82,7 @@ def __init__(
         self._skipped_bytes = 0
 
     @property
-    def in_channel(self):
+    def in_channel(self) -> Optional[Union[int, Tuple[int, ...]]]:
         """The incoming MIDI channel. Must be 0-15. Correlates to MIDI channels 1-16, e.g.
         ``in_channel = 3`` will listen on MIDI channel 4.
         Can also listen on multiple channels, e.g. ``in_channel  = (0,1,2)``
@@ -87,7 +91,7 @@ def in_channel(self):
         return self._in_channel
 
     @in_channel.setter
-    def in_channel(self, channel):
+    def in_channel(self, channel: Optional[Union[str, int, Tuple[int, ...]]]) -> None:
         if channel is None or channel == "ALL":
             self._in_channel = tuple(range(16))
         elif isinstance(channel, int) and 0 <= channel <= 15:
@@ -98,18 +102,20 @@ def in_channel(self, channel):
             raise RuntimeError("Invalid input channel")
 
     @property
-    def out_channel(self):
+    def out_channel(self) -> int:
         """The outgoing MIDI channel. Must be 0-15. Correlates to MIDI channels 1-16, e.g.
-        ``out_channel = 3`` will send to MIDI channel 4. Default is 0 (MIDI channel 1)."""
+        ``out_channel = 3`` will send to MIDI channel 4. Default is 0 (MIDI channel 1).
+        """
         return self._out_channel
 
     @out_channel.setter
-    def out_channel(self, channel):
+    def out_channel(self, channel: Optional[int]) -> None:
+        assert channel is not None
         if not 0 <= channel <= 15:
             raise RuntimeError("Invalid output channel")
         self._out_channel = channel
 
-    def receive(self):
+    def receive(self) -> Optional[MIDIMessage]:
         """Read messages from MIDI port, store them in internal read buffer, then parse that data
         and return the first MIDI message (event).
         This maintains the blocking characteristics of the midi_in port.
@@ -120,6 +126,7 @@ def receive(self):
         # If the buffer here is not full then read as much as we can fit from
         # the input port
         if len(self._in_buf) < self._in_buf_size:
+            assert self._midi_in is not None
             bytes_in = self._midi_in.read(self._in_buf_size - len(self._in_buf))
             if bytes_in:
                 if self._debug:
@@ -140,7 +147,7 @@ def receive(self):
         # msg could still be None at this point, e.g. in middle of monster SysEx
         return msg
 
-    def send(self, msg, channel=None):
+    def send(self, msg: MIDIMessage, channel: Optional[int] = None) -> None:
         """Sends a MIDI message.
 
         :param msg: Either a MIDIMessage object or a sequence (list) of MIDIMessage objects.
@@ -164,7 +171,8 @@ def send(self, msg, channel=None):
 
         self._send(data, len(data))
 
-    def _send(self, packet, num):
+    def _send(self, packet: bytes, num: int) -> None:
         if self._debug:
             print("Sending: ", [hex(i) for i in packet[:num]])
+        assert self._midi_out is not None
         self._midi_out.write(packet, num)

adafruit_midi/midi_message.py

@@ -25,12 +25,19 @@
 __version__ = "0.0.0+auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_MIDI.git"
 
+try:
+    from typing import Union, Tuple, Any, List, Optional, Dict
+except ImportError:
+    pass
+
 # From C3 - A and B are above G
 # Semitones     A   B   C   D   E   F   G
 NOTE_OFFSET = [21, 23, 12, 14, 16, 17, 19]
 
 
-def channel_filter(channel, channel_spec):
+def channel_filter(
+    channel: int, channel_spec: Optional[Union[int, Tuple[int, ...]]]
+) -> bool:
     """
     Utility function to return True iff the given channel matches channel_spec.
     """
@@ -41,13 +48,12 @@ def channel_filter(channel, channel_spec):
     raise ValueError("Incorrect type for channel_spec" + str(type(channel_spec)))
 
 
-def note_parser(note):
+def note_parser(note: Union[int, str]) -> int:
     """If note is a string then it will be parsed and converted to a MIDI note (key) number, e.g.
     "C4" will return 60, "C#4" will return 61. If note is not a string it will simply be returned.
 
     :param note: Either 0-127 int or a str representing the note, e.g. "C#4"
     """
-    midi_note = note
     if isinstance(note, str):
         if len(note) < 2:
             raise ValueError("Bad note format")
@@ -61,7 +67,8 @@ def note_parser(note):
             sharpen = -1
         # int may throw exception here
         midi_note = int(note[1 + abs(sharpen) :]) * 12 + NOTE_OFFSET[noteidx] + sharpen
-
+    elif isinstance(note, int):
+        midi_note = note
     return midi_note
 
 
@@ -82,57 +89,70 @@ class MIDIMessage:
     This is an *abstract* class.
     """
 
-    _STATUS = None
+    _STATUS: Optional[int] = None
     _STATUSMASK = None
-    LENGTH = None
+    LENGTH: Optional[int] = None
     CHANNELMASK = 0x0F
     ENDSTATUS = None
 
     # Commonly used exceptions to save memory
     @staticmethod
-    def _raise_valueerror_oor():
+    def _raise_valueerror_oor() -> None:
         raise ValueError("Out of range")
 
     # Each element is ((status, mask), class)
     # order is more specific masks first
-    _statusandmask_to_class = []
+    # Add better type hints for status, mask, class referenced above
+    _statusandmask_to_class: List[
+        Tuple[Tuple[Optional[bytes], Optional[int]], "MIDIMessage"]
+    ] = []
 
-    def __init__(self, *, channel=None):
+    def __init__(self, *, channel: Optional[int] = None) -> None:
         self._channel = channel  # dealing with pylint inadequacy
         self.channel = channel
 
     @property
-    def channel(self):
+    def channel(self) -> Optional[int]:
         """The channel number of the MIDI message where appropriate.
         This is *updated* by MIDI.send() method.
         """
         return self._channel
 
     @channel.setter
-    def channel(self, channel):
+    def channel(self, channel: int) -> None:
         if channel is not None and not 0 <= channel <= 15:
             raise ValueError("Channel must be 0-15 or None")
         self._channel = channel
 
     @classmethod
-    def register_message_type(cls):
+    def register_message_type(cls) -> None:
         """Register a new message by its status value and mask.
         This is called automagically at ``import`` time for each message.
         """
         ### These must be inserted with more specific masks first
         insert_idx = len(MIDIMessage._statusandmask_to_class)
         for idx, m_type in enumerate(MIDIMessage._statusandmask_to_class):
+            assert cls._STATUSMASK is not None
             if cls._STATUSMASK > m_type[0][1]:
                 insert_idx = idx
                 break
 
+        assert cls._STATUS is not None
+        assert cls._STATUSMASK is not None
         MIDIMessage._statusandmask_to_class.insert(
             insert_idx, ((cls._STATUS, cls._STATUSMASK), cls)
         )
 
     # pylint: disable=too-many-arguments
     @classmethod
-    def _search_eom_status(cls, buf, eom_status, msgstartidx, msgendidxplusone, endidx):
+    def _search_eom_status(
+        cls,
+        buf: Dict[int, bool],
+        eom_status: bool,
+        msgstartidx: int,
+        msgendidxplusone: int,
+        endidx: int,
+    ) -> Tuple[int, bool, bool]:
         good_termination = False
         bad_termination = False
 
@@ -155,14 +175,17 @@ def _search_eom_status(cls, buf, eom_status, msgstartidx, msgendidxplusone, endi
         return (msgendidxplusone, good_termination, bad_termination)
 
     @classmethod
-    def _match_message_status(cls, buf, msgstartidx, msgendidxplusone, endidx):
+    def _match_message_status(
+        cls, buf: bytearray, msgstartidx: int, msgendidxplusone: int, endidx: int
+    ) -> Tuple[Optional[Any], bool, bool, bool, bool, int]:
         msgclass = None
         status = buf[msgstartidx]
         known_msg = False
         complete_msg = False
         bad_termination = False
 
         # Rummage through our list looking for a status match
+        assert msgclass is not None
         for status_mask, msgclass in MIDIMessage._statusandmask_to_class:
             masked_status = status & status_mask[1]
             if status_mask[0] == masked_status:
@@ -198,7 +221,9 @@ def _match_message_status(cls, buf, msgstartidx, msgendidxplusone, endidx):
 
     # pylint: disable=too-many-locals,too-many-branches
     @classmethod
-    def from_message_bytes(cls, midibytes, channel_in):
+    def from_message_bytes(
+        cls, midibytes: bytearray, channel_in: Optional[Union[int, Tuple[int, ...]]]
+    ) -> Tuple[Optional["MIDIMessage"], int, int]:
         """Create an appropriate object of the correct class for the
         first message found in some MIDI bytes filtered by channel_in.
 
@@ -240,6 +265,7 @@ def from_message_bytes(cls, midibytes, channel_in):
             channel_match_orna = True
             if complete_message and not bad_termination:
                 try:
+                    assert msgclass is not None
                     msg = msgclass.from_bytes(midibytes[msgstartidx:msgendidxplusone])
                     if msg.channel is not None:
                         channel_match_orna = channel_filter(msg.channel, channel_in)
@@ -270,17 +296,18 @@ def from_message_bytes(cls, midibytes, channel_in):
 
     # A default method for constructing wire messages with no data.
     # Returns an (immutable) bytes with just the status code in.
-    def __bytes__(self):
+    def __bytes__(self) -> bytes:
         """Return the ``bytes`` wire protocol representation of the object
         with channel number applied where appropriate."""
+        assert self._STATUS is not None
         return bytes([self._STATUS])
 
     # databytes value present to keep interface uniform but unused
     # A default method for constructing message objects with no data.
     # Returns the new object.
     # pylint: disable=unused-argument
     @classmethod
-    def from_bytes(cls, msg_bytes):
+    def from_bytes(cls, msg_bytes: bytes) -> "MIDIMessage":
         """Creates an object from the byte stream of the wire protocol
         representation of the MIDI message."""
         return cls()
@@ -298,7 +325,7 @@ class MIDIUnknownEvent(MIDIMessage):
 
     LENGTH = -1
 
-    def __init__(self, status):
+    def __init__(self, status: int):
         self.status = status
         super().__init__()
 
@@ -316,7 +343,7 @@ class MIDIBadEvent(MIDIMessage):
 
     LENGTH = -1
 
-    def __init__(self, msg_bytes, exception):
+    def __init__(self, msg_bytes: bytearray, exception: Exception):
         self.data = bytes(msg_bytes)
         self.exception_text = repr(exception)
         super().__init__()