Merge pull request #4888 from radarhere/bugfix/ifdrational-equality

Fix IFDRational __eq__ bug

Tests/test_file_jpeg.py

@@ -242,6 +242,16 @@ class TestFileJpeg:
         # Assert
         assert exif[gps_index] == expected_exif_gps
 
+    def test_exif_equality(self):
+        # In 7.2.0, Exif rationals were changed to be read as
+        # TiffImagePlugin.IFDRational. This class had a bug in __eq__,
+        # breaking the self-equality of Exif data
+        exifs = []
+        for i in range(2):
+            with Image.open("Tests/images/exif-200dpcm.jpg") as im:
+                exifs.append(im._getexif())
+        assert exifs[0] == exifs[1]
+
     def test_exif_rollback(self):
         # rolling back exif support in 3.1 to pre-3.0 formatting.
         # expected from 2.9, with b/u qualifiers switched for 3.2 compatibility

Tests/test_tiff_ifdrational.py

@@ -29,6 +29,12 @@ def test_sanity():
     _test_equal(1, 2, IFDRational(1, 2))
 
 
+def test_ranges():
+    for num in range(1, 10):
+        for denom in range(1, 10):
+            assert IFDRational(num, denom) == IFDRational(num, denom)
+
+
 def test_nonetype():
     # Fails if the _delegate function doesn't return a valid function
 

src/PIL/TiffImagePlugin.py

@@ -353,6 +353,8 @@ class IFDRational(Rational):
         return self._val.__hash__()
 
     def __eq__(self, other):
+        if isinstance(other, IFDRational):
+            other = other._val
         return self._val == other
 
     def _delegate(op):