fix(tests): replace ImageMath.eval with ImageMath.unsafe_eval (#364)

Signed-off-by: Alexander Piskun <[email protected]>

Author: bigcat88

tests/helpers.py

@@ -42,7 +42,7 @@ def assert_image_similar(a, b, epsilon=0.0):
     a, b = convert_to_comparable(a, b)
     diff = 0
     for ach, bch in zip(a.split(), b.split()):
-        ch_diff = ImageMath.eval("abs(a - b)", a=ach, b=bch).convert("L")
+        ch_diff = ImageMath.unsafe_eval("abs(a - b)", a=ach, b=bch).convert("L")
         diff += sum(i * num for i, num in enumerate(ch_diff.histogram()))
     ave_diff = diff / (a.size[0] * a.size[1])
     assert epsilon >= ave_diff