Added Type Annotations

Author: isacben

adafruit_bitmap_font/bdf.py

@@ -22,8 +22,15 @@
 
 """
 
+try:
+    from typing import Union, Optional, Tuple
+except ImportError:
+    pass
+
 import gc
+from io import FileIO
 from fontio import Glyph
+from displayio import Bitmap
 from .glyph_cache import GlyphCache
 
 __version__ = "0.0.0-auto.0"
@@ -33,7 +40,7 @@
 class BDF(GlyphCache):
     """Loads glyphs from a BDF file in the given bitmap_class."""
 
-    def __init__(self, f, bitmap_class):
+    def __init__(self, f: FileIO, bitmap_class: Bitmap) -> None:
         super().__init__()
         self.file = f
         self.name = f
@@ -50,7 +57,7 @@ def __init__(self, f, bitmap_class):
         self._descent = None
 
     @property
-    def descent(self):
+    def descent(self) -> Optional[int]:
         """The number of pixels below the baseline of a typical descender"""
         if self._descent is None:
             self.file.seek(0)
@@ -66,7 +73,7 @@ def descent(self):
         return self._descent
 
     @property
-    def ascent(self):
+    def ascent(self) -> Optional[int]:
         """The number of pixels above the baseline of a typical ascender"""
         if self._ascent is None:
             self.file.seek(0)
@@ -81,7 +88,7 @@ def ascent(self):
 
         return self._ascent
 
-    def _verify_bounding_box(self):
+    def _verify_bounding_box(self) -> None:
         """Private function to verify FOUNTBOUNDINGBOX parameter
         This function will parse the first 10 lines of the font source
         file to verify the value or raise an exception in case is not found
@@ -105,15 +112,15 @@ def _verify_bounding_box(self):
                 "Source file does not have the FOUNTBOUNDINGBOX parameter"
             ) from error
 
-    def _readline_file(self):
+    def _readline_file(self) -> str:
         line = self.file.readline()
         return str(line, "utf-8")
 
-    def get_bounding_box(self):
+    def get_bounding_box(self) -> Tuple[int, int, int, int]:
         """Return the maximum glyph size as a 4-tuple of: width, height, x_offset, y_offset"""
         return self._boundingbox
 
-    def load_glyphs(self, code_points):
+    def load_glyphs(self, code_points: Union[int, str, set]) -> None:
         # pylint: disable=too-many-statements,too-many-branches,too-many-nested-blocks,too-many-locals
         metadata = True
         character = False

adafruit_bitmap_font/bitmap_font.py

@@ -22,30 +22,34 @@
 
 """
 
+try:
+    from typing import Optional, Union
+except ImportError:
+    pass
+
+from displayio import Bitmap
+from . import bdf
+from . import pcf
+from . import ttf
+
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_Bitmap_Font.git"
 
 
-def load_font(filename, bitmap=None):
+def load_font(
+    filename: str, bitmap: Optional[Bitmap] = None
+) -> Union[bdf.BDF, pcf.PCF, ttf.TTF, None]:
     """Loads a font file. Returns None if unsupported."""
     # pylint: disable=import-outside-toplevel, consider-using-with
     if not bitmap:
-        import displayio
-
-        bitmap = displayio.Bitmap
+        bitmap = Bitmap
     font_file = open(filename, "rb")
     first_four = font_file.read(4)
     if filename.endswith("bdf") and first_four == b"STAR":
-        from . import bdf
-
         return bdf.BDF(font_file, bitmap)
     if filename.endswith("pcf") and first_four == b"\x01fcp":
-        from . import pcf
-
         return pcf.PCF(font_file, bitmap)
     if filename.endswith("ttf") and first_four == b"\x00\x01\x00\x00":
-        from . import ttf
-
         return ttf.TTF(font_file, bitmap)
 
     raise ValueError("Unknown magic number %r" % first_four)

adafruit_bitmap_font/glyph_cache.py

@@ -22,7 +22,13 @@
 
 """
 
+try:
+    from typing import Union, Optional
+except ImportError:
+    pass
+
 import gc
+from fontio import Glyph
 
 __version__ = "0.0.0-auto.0"
 __repo__ = "https://github.com/adafruit/Adafruit_CircuitPython_Bitmap_Font.git"
@@ -31,13 +37,13 @@
 class GlyphCache:
     """Caches glyphs loaded by a subclass."""
 
-    def __init__(self):
+    def __init__(self) -> None:
         self._glyphs = {}
 
-    def load_glyphs(self, code_points):
+    def load_glyphs(self, code_points: Union[int, str, set]) -> None:
         """Loads displayio.Glyph objects into the GlyphCache from the font."""
 
-    def get_glyph(self, code_point):
+    def get_glyph(self, code_point: int) -> Optional[Glyph]:
         """Returns a displayio.Glyph for the given code point or None is unsupported."""
         if code_point in self._glyphs:
             return self._glyphs[code_point]

adafruit_bitmap_font/pcf.py

@@ -22,12 +22,18 @@
 
 """
 
+try:
+    from typing import Union, Generator
+except ImportError:
+    pass
+
 from collections import namedtuple
 import gc
 import struct
+from io import FileIO
 from micropython import const
-
 from fontio import Glyph
+from displayio import Bitmap as displayioBitmap
 from .glyph_cache import GlyphCache
 
 try:
@@ -96,7 +102,7 @@
 class PCF(GlyphCache):
     """Loads glyphs from a PCF file in the given bitmap_class."""
 
-    def __init__(self, f, bitmap_class):
+    def __init__(self, f: FileIO, bitmap_class: displayioBitmap) -> None:
         super().__init__()
         self.file = f
         self.name = f
@@ -133,27 +139,27 @@ def __init__(self, f, bitmap_class):
         )
 
     @property
-    def ascent(self):
+    def ascent(self) -> int:
         """The number of pixels above the baseline of a typical ascender"""
         return self._ascent
 
     @property
-    def descent(self):
+    def descent(self) -> int:
         """The number of pixels below the baseline of a typical descender"""
         return self._descent
 
-    def get_bounding_box(self):
+    def get_bounding_box(self) -> tuple:
         """Return the maximum glyph size as a 4-tuple of: width, height, x_offset, y_offset"""
         return self._bounding_box
 
-    def _read(self, format_):
+    def _read(self, format_: str) -> tuple:
         size = struct.calcsize(format_)
         if size != len(self.buffer):
             self.buffer = bytearray(size)
         self.file.readinto(self.buffer)
         return struct.unpack_from(format_, self.buffer)
 
-    def _seek_table(self, table):
+    def _seek_table(self, table: dict) -> int:
         self.file.seek(table.offset)
         (format_,) = self._read("<I")
 
@@ -162,13 +168,13 @@ def _seek_table(self, table):
 
         return format_
 
-    def _read_encoding_table(self):
+    def _read_encoding_table(self) -> Encoding:
         encoding = self.tables[_PCF_BDF_ENCODINGS]
         self._seek_table(encoding)
 
         return Encoding(*self._read(">hhhhh"))
 
-    def _read_bitmap_table(self):
+    def _read_bitmap_table(self) -> Bitmap:
         bitmaps = self.tables[_PCF_BITMAPS]
         format_ = self._seek_table(bitmaps)
 
@@ -177,7 +183,7 @@ def _read_bitmap_table(self):
         bitmap_sizes = self._read(">4I")
         return Bitmap(glyph_count, bitmap_sizes[format_ & 3])
 
-    def _read_metrics(self, compressed_metrics):
+    def _read_metrics(self, compressed_metrics: bool) -> Metrics:
         if compressed_metrics:
             (
                 left_side_bearing,
@@ -210,7 +216,7 @@ def _read_metrics(self, compressed_metrics):
             attributes,
         )
 
-    def _read_accelerator_tables(self):
+    def _read_accelerator_tables(self) -> Accelerators:
         # pylint: disable=too-many-locals
         accelerators = self.tables.get(_PCF_BDF_ACCELERATORS)
         if not accelerators:
@@ -260,7 +266,7 @@ def _read_accelerator_tables(self):
             ink_maxbounds,
         )
 
-    def _read_properties(self):
+    def _read_properties(self) -> Generator[tuple, None, None]:
         property_table_offset = self.tables[_PCF_PROPERTIES]["offset"]
         self.file.seek(property_table_offset)
         (format_,) = self._read("<I")
@@ -291,7 +297,7 @@ def _read_properties(self):
             else:
                 yield (string_map[name_offset], value)
 
-    def load_glyphs(self, code_points):
+    def load_glyphs(self, code_points: Union[int, str, set]) -> None:
         # pylint: disable=too-many-statements,too-many-branches,too-many-nested-blocks,too-many-locals
         if isinstance(code_points, int):
             code_points = (code_points,)

adafruit_bitmap_font/ttf.py

@@ -6,19 +6,20 @@
 # Remove the above when TTF is actually supported.
 
 import struct
-
+from io import FileIO
+from displayio import Bitmap
 
 # https://developer.apple.com/fonts/TrueType-Reference-Manual/RM06/Chap6glyf.html
 
 
 class TTF:
-    def __init__(self, f, bitmap):
+    def __init__(self, f: FileIO, bitmap: Bitmap) -> None:
         f.seek(0)
         self.file = f
 
         self.characters = {}
 
-        def read(format):
+        def read(format: str) -> tuple:
             s = struct.calcsize(format)
             return struct.unpack_from(format, f.read(s))