Blacken & fix pylint

Author: jepler

CircuitPython_BLEThermalPrinter/code.py

@@ -1,16 +1,9 @@
-import seekablebitmap
-
-import gc
 import os
-import struct
-import time
 
 import board
-import digitalio
 import keypad
 import ulab.numpy as np
 
-import adafruit_ble
 from adafruit_ble import BLERadio
 from adafruit_ble.advertising import Advertisement
 
@@ -21,41 +14,6 @@
 
 buttons = keypad.Keys([board.BUTTON_A, board.BUTTON_B], value_when_pressed=False)
 
-def pnmopen(filename):
-    """
-    Scan for netpbm format info, skip over comments, and read header data.
-
-    Return the format, header, and the opened file positioned at the start of
-    the bitmap data.
-    """
-    # pylint: disable=too-many-branches
-    image_file = open(filename, "rb")
-    magic_number = image_file.read(2)
-    image_file.seek(2)
-    pnm_header = []
-    next_value = bytearray()
-    while True:
-        # We have all we need at length 3 for formats P2, P3, P5, P6
-        if len(pnm_header) == 3:
-            return image_file, magic_number, pnm_header
-
-        if len(pnm_header) == 2 and magic_number in [b"P1", b"P4"]:
-            return image_file, magic_number, pnm_header
-
-        next_byte = image_file.read(1)
-        if next_byte == b"":
-            raise RuntimeError("Unsupported image format {}".format(magic_number))
-        if next_byte == b"#":  # comment found, seek until a newline or EOF is found
-            while image_file.read(1) not in [b"", b"\n"]:  # EOF or NL
-                pass
-        elif not next_byte.isdigit():  # boundary found in header data
-            if next_value:
-                # pull values until space is found
-                pnm_header.append(int("".join(["%c" % char for char in next_value])))
-                next_value = bytearray()  # reset the byte array
-        else:
-            next_value += next_byte  # push the digit into the byte array
-
 def wait_for_press(kbd):
     """
     Wait for a keypress and return the event
@@ -65,6 +23,7 @@ def wait_for_press(kbd):
         if event and event.pressed:
             return event
 
+
 def show(s):
     """
     Display a message on the screen
@@ -74,43 +33,54 @@ def show(s):
     print(s)
     board.DISPLAY.auto_refresh = True
 
+
 def show_error(s):
     """
     Display a message on the screen and wait for a button press
     """
     show(s + "\nPress a button to continue")
     wait_for_press(buttons)
 
+
 def find_cat_printer(radio):
     """
     Connect to the cat printer device using BLE
     """
     while True:
         show("Scanning for GB02 device...")
         for adv in radio.start_scan(Advertisement):
-            complete_name = getattr(adv, 'complete_name')
+            complete_name = getattr(adv, "complete_name")
             if complete_name is not None:
                 print(f"Saw {complete_name}")
-            if complete_name == 'GB02':
+            if complete_name == "GB02":
                 radio.stop_scan()
                 return radio.connect(adv, timeout=10)[CatPrinter]
 
-image_files = [i for i in os.listdir('/') if i.lower().endswith(".pbm") or i.lower().endswith(".bmp")]
+
+image_files = [
+    i
+    for i in os.listdir("/")
+    if i.lower().endswith(".pbm") or i.lower().endswith(".bmp")
+]
 image_files.sort(key=lambda filename: filename.lower())
 
+
 def select_image():
     i = 0
     while True:
-        show(f"Select image file\nA: next image\nB: print this image\n\n{image_files[i]}")
+        show(
+            f"Select image file\nA: next image\nB: print this image\n\n{image_files[i]}"
+        )
         event = wait_for_press(buttons)
-        if event.key_number == 0: # button "A"
+        if event.key_number == 0:  # button "A"
             i = (i + 1) % len(image_files)
-        if event.key_number == 1: # button "B"
+        if event.key_number == 1:  # button "B"
             return image_files[i]
-    
+
+
 printer = find_cat_printer(ble)
 
-while True:
+def main():
     try:
         filename = select_image()
 
@@ -134,9 +104,11 @@ def select_image():
 
         # Print blank lines until the paper can be torn off
         for i in range(80):
-            printer.print_bitmap_row(b'\0' * 48)
+            printer.print_bitmap_row(b"\0" * 48)
 
-    except Exception as e:
+    except Exception as e: # pylint: disable=broad-except
         show_error(str(e))
         image_files.remove(filename)
-        continue
+
+while True:
+    main()

CircuitPython_BLEThermalPrinter/seekablebitmap.py

@@ -1,13 +1,29 @@
 import struct
-import ulab
+
+# pylint: disable=consider-using-with
 
 class SeekableBitmap:
-    def __init__(self, image_file, width, height, bits_per_pixel, *, bytes_per_row=None, data_start=None, stride=None, palette=None):
+    """Allow random access to an uncompressed bitmap file on disk"""
+    def __init__(
+        self,
+        image_file,
+        width,
+        height,
+        bits_per_pixel,
+        *,
+        bytes_per_row=None,
+        data_start=None,
+        stride=None,
+        palette=None,
+    ):
+        """Construct a SeekableBitmap"""
         self.image_file = image_file
         self.width = width
         self.height = height
         self.bits_per_pixel = bits_per_pixel
-        self.bytes_per_row = bytes_per_row if bytes_per_row else (bits_per_pixel * width + 7) // 8
+        self.bytes_per_row = (
+            bytes_per_row if bytes_per_row else (bits_per_pixel * width + 7) // 8
+        )
         self.stride = stride if stride else self.bytes_per_row
         self.palette = palette
         self.data_start = data_start if data_start else image_file.tell()
@@ -16,6 +32,7 @@ def get_row(self, row):
         self.image_file.seek(self.data_start + row * self.stride)
         return self.image_file.read(self.bytes_per_row)
 
+
 def _pnmopen(filename):
     """
     Scan for netpbm format info, skip over comments, and read header data.
@@ -51,40 +68,71 @@ def _pnmopen(filename):
         else:
             next_value += next_byte  # push the digit into the byte array
 
+
 def pnmopen(filename):
+    """
+    Interpret netpbm format info and construct a SeekableBitmap
+    """
     image_file, magic_number, pnm_header = _pnmopen(filename)
-    if magic_number == b'P4':
-        return SeekableBitmap(image_file, pnm_header[0], pnm_header[1], 1, palette=b'\xff\xff\xff\x00\x00\x00\x00\x00')
-    if magic_number == b'P5':
-        return SeekableBitmap(image_file, pnm_header[0], pnm_header[1], pnm_header[2].bit_length())
-    if magic_number == b'P6':
-        return SeekableBitmap(image_file, pnm_header[0], pnm_header[1], 3*pnm_header[2].bit_length())
+    if magic_number == b"P4":
+        return SeekableBitmap(
+            image_file,
+            pnm_header[0],
+            pnm_header[1],
+            1,
+            palette=b"\xff\xff\xff\x00\x00\x00\x00\x00",
+        )
+    if magic_number == b"P5":
+        return SeekableBitmap(
+            image_file, pnm_header[0], pnm_header[1], pnm_header[2].bit_length()
+        )
+    if magic_number == b"P6":
+        return SeekableBitmap(
+            image_file, pnm_header[0], pnm_header[1], 3 * pnm_header[2].bit_length()
+        )
     raise ValueError(f"Unknown or unsupported magic number {magic_number}")
 
+
 def bmpopen(filename):
+    """
+    Interpret bmp format info and construct a SeekableBitmap
+    """
     image_file = open(filename, "rb")
 
     header = image_file.read(34)
 
-    data_start, header_size, width, height, planes, bits_per_pixel, method = struct.unpack("<10x4l2hl", header)
+    data_start, header_size, width, height, _, bits_per_pixel, _ = struct.unpack(
+        "<10x4l2hl", header
+    )
 
     bits_per_pixel = bits_per_pixel if bits_per_pixel != 0 else 1
 
-    mask_size = (12 if header_size < 56 else 16) if method == 3 else 0
     palette_start = header_size + 14
     image_file.seek(palette_start)
     palette = image_file.read(4 << bits_per_pixel)
 
-    stride=(bits_per_pixel*width+31)//32*4
+    stride = (bits_per_pixel * width + 31) // 32 * 4
     if height < 0:
         height = -height
     else:
         data_start = data_start + stride * (height - 1)
         stride = -stride
 
-    return SeekableBitmap(image_file, width, height, bits_per_pixel, data_start=data_start, stride=stride, palette=palette)
+    return SeekableBitmap(
+        image_file,
+        width,
+        height,
+        bits_per_pixel,
+        data_start=data_start,
+        stride=stride,
+        palette=palette,
+    )
+
 
 def imageopen(filename):
+    """
+    Open a bmp or pnm file as a seekable bitmap
+    """
     if filename.lower().endswith(".bmp"):
         return bmpopen(filename)
     return pnmopen(filename)

CircuitPython_BLEThermalPrinter/thermalprinter.py

@@ -1,15 +1,9 @@
 # Protocol information from Thermal_Printer Arduino library
 # https://github.com/bitbank2/Thermal_Printer/
-import collections
-import time
 from adafruit_ble.uuid import StandardUUID
 from adafruit_ble.services import Service
 from adafruit_ble.characteristics.stream import StreamIn
 
-PrinterConfig = collections.namedtuple(
-    "PrinterConfig", ("width", "service", "characteristic")
-)
-
 # Switch the printing mode to bitmap
 printimage = b"Qx\xbe\x00\x01\x00\x00\x00\xff"
 # Switch the printing mode to text
@@ -19,10 +13,44 @@
 
 # this table helps compute the checksum of transmitted data
 # it is crc-8-ccitt
-checksumtable = b"\x00\x07\x0e\t\x1c\x1b\x12\x158?61$#*-pw~ylkbeHOFATSZ]\xe0\xe7\xee\xe9\xfc\xfb\xf2\xf5\xd8\xdf\xd6\xd1\xc4\xc3\xca\xcd\x90\x97\x9e\x99\x8c\x8b\x82\x85\xa8\xaf\xa6\xa1\xb4\xb3\xba\xbd\xc7\xc0\xc9\xce\xdb\xdc\xd5\xd2\xff\xf8\xf1\xf6\xe3\xe4\xed\xea\xb7\xb0\xb9\xbe\xab\xac\xa5\xa2\x8f\x88\x81\x86\x93\x94\x9d\x9a' ).;<52\x1f\x18\x11\x16\x03\x04\r\nWPY^KLEBohafst}z\x89\x8e\x87\x80\x95\x92\x9b\x9c\xb1\xb6\xbf\xb8\xad\xaa\xa3\xa4\xf9\xfe\xf7\xf0\xe5\xe2\xeb\xec\xc1\xc6\xcf\xc8\xdd\xda\xd3\xd4ing`ur{|QV_XMJCD\x19\x1e\x17\x10\x05\x02\x0b\x0c!&/(=:34NI@GRU\\[vqx\x7fjmdc>907\"%,+\x06\x01\x08\x0f\x1a\x1d\x14\x13\xae\xa9\xa0\xa7\xb2\xb5\xbc\xbb\x96\x91\x98\x9f\x8a\x8d\x84\x83\xde\xd9\xd0\xd7\xc2\xc5\xcc\xcb\xe6\xe1\xe8\xef\xfa\xfd\xf4\xf3"
+checksumtable = (
+    b"\x00\x07\x0e\t\x1c\x1b\x12\x158?61$#*-"
+    b"pw~ylkbeHOFATSZ]"
+    b"\xe0\xe7\xee\xe9\xfc\xfb\xf2\xf5\xd8\xdf\xd6\xd1\xc4\xc3\xca\xcd"
+    b"\x90\x97\x9e\x99\x8c\x8b\x82\x85\xa8\xaf\xa6\xa1\xb4\xb3\xba\xbd"
+    b"\xc7\xc0\xc9\xce\xdb\xdc\xd5\xd2\xff\xf8\xf1\xf6\xe3\xe4\xed\xea"
+    b"\xb7\xb0\xb9\xbe\xab\xac\xa5\xa2\x8f\x88\x81\x86\x93\x94\x9d\x9a"
+    b"' ).;<52\x1f\x18\x11\x16\x03\x04\r\n"
+    b"WPY^KLEBohafst}z"
+    b"\x89\x8e\x87\x80\x95\x92\x9b\x9c\xb1\xb6\xbf\xb8\xad\xaa\xa3\xa4"
+    b"\xf9\xfe\xf7\xf0\xe5\xe2\xeb\xec\xc1\xc6\xcf\xc8\xdd\xda\xd3\xd4"
+    b"ing`ur{|QV_XMJCD"
+    b"\x19\x1e\x17\x10\x05\x02\x0b\x0c!&/(=:34"
+    b"NI@GRU\\[vqx\x7fjmdc"
+    b'>907"%,+\x06\x01\x08\x0f\x1a\x1d\x14\x13'
+    b"\xae\xa9\xa0\xa7\xb2\xb5\xbc\xbb\x96\x91\x98\x9f\x8a\x8d\x84\x83"
+    b"\xde\xd9\xd0\xd7\xc2\xc5\xcc\xcb\xe6\xe1\xe8\xef\xfa\xfd\xf4\xf3"
+)
 
 # mirrortable[i] is the bit reversed version of the byte i
-mirrortable = b"\x00\x80@\xc0 \xa0`\xe0\x10\x90P\xd00\xb0p\xf0\x08\x88H\xc8(\xa8h\xe8\x18\x98X\xd88\xb8x\xf8\x04\x84D\xc4$\xa4d\xe4\x14\x94T\xd44\xb4t\xf4\x0c\x8cL\xcc,\xacl\xec\x1c\x9c\\\xdc<\xbc|\xfc\x02\x82B\xc2\"\xa2b\xe2\x12\x92R\xd22\xb2r\xf2\n\x8aJ\xca*\xaaj\xea\x1a\x9aZ\xda:\xbaz\xfa\x06\x86F\xc6&\xa6f\xe6\x16\x96V\xd66\xb6v\xf6\x0e\x8eN\xce.\xaen\xee\x1e\x9e^\xde>\xbe~\xfe\x01\x81A\xc1!\xa1a\xe1\x11\x91Q\xd11\xb1q\xf1\t\x89I\xc9)\xa9i\xe9\x19\x99Y\xd99\xb9y\xf9\x05\x85E\xc5%\xa5e\xe5\x15\x95U\xd55\xb5u\xf5\r\x8dM\xcd-\xadm\xed\x1d\x9d]\xdd=\xbd}\xfd\x03\x83C\xc3#\xa3c\xe3\x13\x93S\xd33\xb3s\xf3\x0b\x8bK\xcb+\xabk\xeb\x1b\x9b[\xdb;\xbb{\xfb\x07\x87G\xc7'\xa7g\xe7\x17\x97W\xd77\xb7w\xf7\x0f\x8fO\xcf/\xafo\xef\x1f\x9f_\xdf?\xbf\x7f\xff"
+mirrortable = (
+    b"\x00\x80@\xc0 \xa0`\xe0\x10\x90P\xd00\xb0p\xf0"
+    b"\x08\x88H\xc8(\xa8h\xe8\x18\x98X\xd88\xb8x\xf8"
+    b"\x04\x84D\xc4$\xa4d\xe4\x14\x94T\xd44\xb4t\xf4"
+    b"\x0c\x8cL\xcc,\xacl\xec\x1c\x9c\\\xdc<\xbc|\xfc"
+    b'\x02\x82B\xc2"\xa2b\xe2\x12\x92R\xd22\xb2r\xf2'
+    b"\n\x8aJ\xca*\xaaj\xea\x1a\x9aZ\xda:\xbaz\xfa"
+    b"\x06\x86F\xc6&\xa6f\xe6\x16\x96V\xd66\xb6v\xf6"
+    b"\x0e\x8eN\xce.\xaen\xee\x1e\x9e^\xde>\xbe~\xfe"
+    b"\x01\x81A\xc1!\xa1a\xe1\x11\x91Q\xd11\xb1q\xf1"
+    b"\t\x89I\xc9)\xa9i\xe9\x19\x99Y\xd99\xb9y\xf9"
+    b"\x05\x85E\xc5%\xa5e\xe5\x15\x95U\xd55\xb5u\xf5"
+    b"\r\x8dM\xcd-\xadm\xed\x1d\x9d]\xdd=\xbd}\xfd"
+    b"\x03\x83C\xc3#\xa3c\xe3\x13\x93S\xd33\xb3s\xf3"
+    b"\x0b\x8bK\xcb+\xabk\xeb\x1b\x9b[\xdb;\xbb{\xfb"
+    b"\x07\x87G\xc7'\xa7g\xe7\x17\x97W\xd77\xb7w\xf7"
+    b"\x0f\x8fO\xcf/\xafo\xef\x1f\x9f_\xdf?\xbf\x7f\xff"
+)
 
 
 def checksum(data, start, count):
@@ -32,24 +60,17 @@ def checksum(data, start, count):
     return cs
 
 
-PRINTER_CAT = PrinterConfig(width=384, service=0xA3E0, characteristic=0xAE01)
-
 MODE_TEXT = "MODE_TEXT"
 MODE_BITMAP = "MODE_BITMAP"
 
-printers = {"GB02": PRINTER_CAT, "GB01": PRINTER_CAT}
-
 class CatPrinter(Service):
 
     uuid = StandardUUID(0xAE30)
 
-    _tx = StreamIn(uuid=StandardUUID(0xAE01),
-        timeout=1.0,
-        buffer_size=256,
-    )
+    _tx = StreamIn(uuid=StandardUUID(0xAE01), timeout=1.0, buffer_size=256)
 
     def _write_data(self, buf):
-        result = self._tx.write(buf)
+        self._tx.write(buf)
 
     @property
     def bitmap_width(self):
@@ -59,7 +80,6 @@ def __init__(self, service=None):
         super().__init__(service=service)
         self._mode = None
 
-
     @property
     def mode(self):
         return self._mode
@@ -80,14 +100,12 @@ def mode(self, value):
 
     def feed_lines(self, lines):
         buf = bytearray(paperfeed)
-        buf[6] = lines & 0xff
+        buf[6] = lines & 0xFF
         buf[7] = lines >> 8
         buf[8] = checksum(buf, 6, 2)
         self._write_data(buf)
 
     def _print_common(self, text, reverse_bits=True):
-
-        offset = 0
         data = memoryview(text)
         while data:
             sz = min(112, len(data))