Add a lot more type hints

Author: WhyNotHugo

barcode/__init__.py

@@ -30,6 +30,8 @@
 if TYPE_CHECKING:
     import os
 
+    from barcode.writer import BaseWriter
+
 __BARCODE_MAP = {
     "ean8": EAN8,
     "ean8-guard": EAN8_GUARD,
@@ -62,7 +64,7 @@
 def get(
     name: str,
     code: str | None = None,
-    writer=None,
+    writer: BaseWriter | None = None,
     options: dict | None = None,
 ):
     """Helper method for getting a generator or even a generated code.
@@ -87,18 +89,18 @@ def get(
     return barcode
 
 
-def get_class(name):
+def get_class(name: str):
     return get_barcode(name)
 
 
 def generate(
     name: str,
     code: str,
-    writer=None,
+    writer: BaseWriter | None = None,
     output: str | (os.PathLike | (BinaryIO | None)) = None,
     writer_options: dict | None = None,
     text: str | None = None,
-):
+) -> str | None:
     """Shortcut to generate a barcode in one line.
 
     :param name: Name of the type of barcode to use.

barcode/base.py

@@ -3,11 +3,15 @@
 """
 from __future__ import annotations
 
+from typing import TYPE_CHECKING
 from typing import ClassVar
 
 from barcode.writer import BaseWriter
 from barcode.writer import SVGWriter
 
+if TYPE_CHECKING:
+    from typing import BinaryIO
+
 
 class Barcode:
     name = ""
@@ -65,17 +69,18 @@ def save(
 
         return self.writer.save(filename, output)
 
-    def write(self, fp, options=None, text=None):
+    def write(
+        self,
+        fp: BinaryIO,
+        options: dict | None = None,
+        text: str | None = None,
+    ) -> None:
         """Renders the barcode and writes it to the file like object
         `fp`.
 
-        :parameters:
-            fp : File like object
-                Object to write the raw data in.
-            options : Dict
-                The same as in `self.render`.
-            text : str
-                Text to render under the barcode.
+        :param fp: Object to write the raw data in.
+        :param options: The same as in `self.render`.
+        :param text: Text to render under the barcode.
         """
         output = self.render(options, text)
         self.writer.write(output, fp)

barcode/pybarcode.py

@@ -5,13 +5,14 @@
 
 import barcode
 from barcode.version import version
+from barcode.writer import BaseWriter
 from barcode.writer import ImageWriter
 from barcode.writer import SVGWriter
 
 IMG_FORMATS = ("BMP", "GIF", "JPEG", "MSP", "PCX", "PNG", "TIFF", "XBM")
 
 
-def list_types(args, parser=None):
+def list_types(args, parser=None) -> None:
     print("\npython-barcode available barcode formats:")
     print(", ".join(barcode.PROVIDED_BARCODES))
     print("\n")
@@ -24,7 +25,7 @@ def list_types(args, parser=None):
     print("\n")
 
 
-def create_barcode(args, parser):
+def create_barcode(args, parser) -> None:
     args.type = args.type.upper()
     if args.type != "SVG" and args.type not in IMG_FORMATS:
         parser.error(f"Unknown type {args.type}. Try list action for available types.")
@@ -34,8 +35,9 @@ def create_barcode(args, parser):
             f"Unknown barcode {args.barcode}. Try list action for available barcodes."
         )
     if args.type != "SVG":
+        assert ImageWriter is not None
         opts = {"format": args.type}
-        writer = ImageWriter()
+        writer: BaseWriter = ImageWriter()
     else:
         opts = {"compress": args.compress}
         writer = SVGWriter()
@@ -44,7 +46,7 @@ def create_barcode(args, parser):
     print(f"New barcode saved as {name}.")
 
 
-def main():
+def main() -> None:
     msg = []
     if ImageWriter is None:
         msg.append("Image output disabled (Pillow not found), --type option disabled.")

barcode/writer.py

@@ -308,6 +308,9 @@ def render(self, code):
 
         return self._callbacks["finish"]()
 
+    def write(self, content, fp: BinaryIO) -> None:
+        raise NotImplementedError
+
 
 class SVGWriter(BaseWriter):
     def __init__(self) -> None:
@@ -400,7 +403,7 @@ def save(self, filename, output):
                 f.write(output)
         return _filename
 
-    def write(self, content, fp: BinaryIO):
+    def write(self, content, fp: BinaryIO) -> None:
         """Write `content` into a file-like object.
 
         Content should be a barcode rendered by this writer.
@@ -409,7 +412,7 @@ def write(self, content, fp: BinaryIO):
 
 
 if Image is None:
-    ImageWriter = None
+    ImageWriter: type | None = None
 else:
 
     class ImageWriter(BaseWriter):  # type: ignore[no-redef]
@@ -463,15 +466,15 @@ def _paint_text(self, xpos, ypos):
                 )
                 ypos += pt2mm(self.font_size) / 2 + self.text_line_distance
 
-        def _finish(self):
+        def _finish(self) -> Image:
             return self._image
 
-        def save(self, filename, output):
+        def save(self, filename: str, output) -> str:
             filename = f"{filename}.{self.format.lower()}"
             output.save(filename, self.format.upper())
             return filename
 
-        def write(self, content, fp: BinaryIO):
+        def write(self, content, fp: BinaryIO) -> None:
             """Write `content` into a file-like object.
 
             Content should be a barcode rendered by this writer.

tests/test_builds.py

@@ -3,14 +3,14 @@
 from barcode import get_barcode
 
 
-def test_ean8_builds():
+def test_ean8_builds() -> None:
     ref = "1010100011000110100100110101111010101000100100010011100101001000101"
     ean = get_barcode("ean8", "40267708")
     bc = ean.build()
     assert ref == bc[0]
 
 
-def test_ean8_builds_with_longer_bars():
+def test_ean8_builds_with_longer_bars() -> None:
     ref = "G0G01000110001101001001101011110G0G01000100100010011100101001000G0G"
     ean = get_barcode("ean8", "40267708", options={"guardbar": True})
     bc = ean.build()

tests/test_checksums.py

@@ -3,46 +3,46 @@
 from barcode import get_barcode
 
 
-def test_code39_checksum():
+def test_code39_checksum() -> None:
     code39 = get_barcode("code39", "Code39")
     assert code39.get_fullcode() == "CODE39W"
 
 
-def test_pzn_checksum():
+def test_pzn_checksum() -> None:
     pzn = get_barcode("pzn", "103940")
     assert pzn.get_fullcode() == "PZN-1039406"
 
 
-def test_ean13_checksum():
+def test_ean13_checksum() -> None:
     ean = get_barcode("ean13", "400614457735")
     assert ean.get_fullcode() == "4006144577350"
 
 
-def test_ean8_checksum():
+def test_ean8_checksum() -> None:
     ean = get_barcode("ean8", "6032299")
     assert ean.get_fullcode() == "60322999"
 
 
-def test_jan_checksum():
+def test_jan_checksum() -> None:
     jan = get_barcode("jan", "491400614457")
     assert jan.get_fullcode() == "4914006144575"
 
 
-def test_ean14_checksum():
+def test_ean14_checksum() -> None:
     ean = get_barcode("ean14", "1234567891258")
     assert ean.get_fullcode() == "12345678912589"
 
 
-def test_isbn10_checksum():
+def test_isbn10_checksum() -> None:
     isbn = get_barcode("isbn10", "376926085")
     assert isbn.isbn10 == "3769260856"
 
 
-def test_isbn13_checksum():
+def test_isbn13_checksum() -> None:
     isbn = get_barcode("isbn13", "978376926085")
     assert isbn.get_fullcode() == "9783769260854"
 
 
-def test_gs1_128_checksum():
+def test_gs1_128_checksum() -> None:
     gs1_128 = get_barcode("gs1_128", "00376401856400470087")
     assert gs1_128.get_fullcode() == "00376401856400470087"

tests/test_init.py

@@ -12,17 +12,17 @@
 TESTPATH = os.path.join(PATH, "test_outputs")
 
 
-def test_generate_without_output():
+def test_generate_without_output() -> None:
     with pytest.raises(TypeError, match="'output' cannot be None"):
         barcode.generate("ean13", "123455559121112")
 
 
-def test_generate_with_file():
+def test_generate_with_file() -> None:
     with open(os.path.join(TESTPATH, "generate_with_file.jpeg"), "wb") as f:
         barcode.generate("ean13", "123455559121112", output=f)
 
 
-def test_generate_with_filepath():
+def test_generate_with_filepath() -> None:
     # FIXME: extension is added to the filepath even if you include it.
     rv = barcode.generate(
         "ean13",
@@ -32,12 +32,12 @@ def test_generate_with_filepath():
     assert rv == os.path.abspath(os.path.join(TESTPATH, "generate_with_filepath.svg"))
 
 
-def test_generate_with_file_and_writer():
+def test_generate_with_file_and_writer() -> None:
     with open(os.path.join(TESTPATH, "generate_with_file_and_writer.jpeg"), "wb") as f:
         barcode.generate("ean13", "123455559121112", output=f, writer=SVGWriter())
 
 
-def test_generate_with_bytesio():
+def test_generate_with_bytesio() -> None:
     bio = BytesIO()
     barcode.generate("ean13", "123455559121112", output=bio)
     # XXX: File is not 100% deterministic; needs to be addressed at some point.

tests/test_manually.py

@@ -50,15 +50,15 @@
 )
 
 
-def test_generating_barcodes():
+def test_generating_barcodes() -> None:
     os.makedirs(TESTPATH, exist_ok=True)
 
     objects = []
 
-    def append(x, y):
+    def append(x, y) -> None:
         objects.append(OBJECTS.format(filename=x, name=y))
 
-    def append_img(x, y):
+    def append_img(x, y) -> None:
         objects.append(IMAGES.format(filename=x, name=y))
 
     options = {}

tests/test_writers.py

@@ -10,16 +10,20 @@
 PATH = os.path.dirname(os.path.abspath(__file__))
 TESTPATH = os.path.join(PATH, "test_outputs")
 
-if ImageWriter:
+if ImageWriter is not None:
+
+    def test_saving_image_to_byteio() -> None:
+        assert ImageWriter is not None  # workaround for mypy
 
-    def test_saving_image_to_byteio():
         rv = BytesIO()
         EAN13(str(100000902922), writer=ImageWriter()).write(rv)
 
         with open(f"{TESTPATH}/somefile.jpeg", "wb") as f:
             EAN13("100000011111", writer=ImageWriter()).write(f)
 
-    def test_saving_rgba_image():
+    def test_saving_rgba_image() -> None:
+        assert ImageWriter is not None  # workaround for mypy
+
         rv = BytesIO()
         EAN13(str(100000902922), writer=ImageWriter()).write(rv)
 
@@ -31,15 +35,15 @@ def test_saving_rgba_image():
             )
 
 
-def test_saving_svg_to_byteio():
+def test_saving_svg_to_byteio() -> None:
     rv = BytesIO()
     EAN13(str(100000902922), writer=SVGWriter()).write(rv)
 
     with open(f"{TESTPATH}/somefile.svg", "wb") as f:
         EAN13("100000011111", writer=SVGWriter()).write(f)
 
 
-def test_saving_svg_to_byteio_with_guardbar():
+def test_saving_svg_to_byteio_with_guardbar() -> None:
     rv = BytesIO()
     EAN13(str(100000902922), writer=SVGWriter(), guardbar=True).write(rv)