Fix compatibility with PIL version 12

PIL version 12 removed `PIL.Image.isImageType()` (see python-pillow/Pillow#9053).

Closes #41.

Author: dbaty

Changelog.rst

@@ -1,10 +1,10 @@
 ChangeLog
 =========
 
-3.1 (unreleased)
+4.0 (unreleased)
 ----------------
 
-- Nothing changed yet.
+- Fix support of PIL (Pillow) 12.
 
 
 3.0 (2020-01-02)

setup.cfg

@@ -1,6 +1,6 @@
 [metadata]
 name = zbarlight
-version = 3.1.dev0
+version = 4.0.dev0
 author = Polyconseil
 author_email = [email protected]
 url = https://github.com/Polyconseil/zbarlight

src/zbarlight/__init__.py

@@ -3,6 +3,7 @@
 import pkg_resources
 from PIL import Image
 
+from . import compat
 from ._zbarlight import Symbologies
 from ._zbarlight import zbar_code_scanner
 
@@ -65,7 +66,7 @@ def scan_codes(code_types, image):
         raise UnknownSymbologieError('Unknown Symbologies: %s' % bad_code_types)
 
     # Convert the image to be used by c-extension
-    if not Image.isImageType(image):
+    if not compat.is_image(image):
         raise RuntimeError('Bad or unknown image format')
     converted_image = image.convert('L')  # Convert image to gray scale (8 bits per pixel).
     raw = converted_image.tobytes()  # Get image data.

src/zbarlight/compat.py

@@ -0,0 +1,9 @@
+# FIXME: this could probably be removed by properly typing
+# `zbarlight.scan_codes()`.
+try:
+    from PIL import Image
+    is_image = Image.isImageType
+except AttributeError:
+    # Image.isImageType has been removed from PIL 12.0
+    def is_image(im):
+        return isinstance(im, Image.Image)