Use pytest.approx, pytest.raises and pytest.skip

Tests/test_file_gif.py

@@ -422,12 +422,11 @@ def test_seek() -> None:
     with Image.open("Tests/images/dispose_none.gif") as img:
         assert isinstance(img, GifImagePlugin.GifImageFile)
         frame_count = 0
-        try:
+        with pytest.raises(EOFError):
             while True:
                 frame_count += 1
                 img.seek(img.tell() + 1)
-        except EOFError:
-            assert frame_count == 5
+        assert frame_count == 5
 
         img.seek(0)
         with pytest.raises(ValueError, match="cannot seek to frame 2"):

Tests/test_file_gimpgradient.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+import pytest
+
 from PIL import GimpGradientFile, ImagePalette
 
 
@@ -84,7 +86,7 @@ def test_sphere_increasing() -> None:
     ret = GimpGradientFile.sphere_increasing(middle, pos)
 
     # Assert
-    assert round(abs(ret - 0.9682458365518543), 7) == 0
+    assert ret == pytest.approx(0.9682458365518543)
 
 
 def test_sphere_decreasing() -> None:

Tests/test_file_libtiff.py

@@ -321,7 +321,7 @@ def check_tags(
                         and libtiff
                     ):
                         # libtiff does not support real RATIONALS
-                        assert round(abs(float(reloaded_value) - float(value)), 7) == 0
+                        assert reloaded_value == pytest.approx(value)
                         continue
 
                     assert reloaded_value == value

Tests/test_file_palm.py

@@ -36,7 +36,7 @@ def open_with_magick(magick: list[str], tmp_path: Path, f: str) -> Image.Image:
 def roundtrip(tmp_path: Path, mode: str) -> None:
     magick = magick_command()
     if not magick:
-        return
+        pytest.skip("ImageMagick not available")
 
     im = hopper(mode)
     outfile = str(tmp_path / "temp.palm")

Tests/test_file_tiff_metadata.py

@@ -72,9 +72,9 @@ def test_rt_metadata(tmp_path: Path) -> None:
         assert loaded.tag_v2[ImageDescription] == reloaded_text_data
 
         loaded_float = loaded.tag[TAG_IDS["RollAngle"]][0]
-        assert round(abs(loaded_float - float_data), 5) == 0
+        assert loaded_float == pytest.approx(float_data)
         loaded_double = loaded.tag[TAG_IDS["YawAngle"]][0]
-        assert round(abs(loaded_double - double_data), 7) == 0
+        assert loaded_double == pytest.approx(double_data)
 
     # check with 2 element ImageJMetaDataByteCounts, issue #2006
 

Tests/test_image_entropy.py

@@ -1,18 +1,20 @@
 from __future__ import annotations
 
+import pytest
+
 from .helper import hopper
 
 
 def test_entropy() -> None:
     def entropy(mode: str) -> float:
         return hopper(mode).entropy()
 
-    assert round(abs(entropy("1") - 0.9138803254693582), 7) == 0
-    assert round(abs(entropy("L") - 7.063008716585465), 7) == 0
-    assert round(abs(entropy("I") - 7.063008716585465), 7) == 0
-    assert round(abs(entropy("F") - 7.063008716585465), 7) == 0
-    assert round(abs(entropy("P") - 5.082506854662517), 7) == 0
-    assert round(abs(entropy("RGB") - 8.821286587714319), 7) == 0
-    assert round(abs(entropy("RGBA") - 7.42724306524488), 7) == 0
-    assert round(abs(entropy("CMYK") - 7.4272430652448795), 7) == 0
-    assert round(abs(entropy("YCbCr") - 7.698360534903628), 7) == 0
+    assert entropy("1") == pytest.approx(0.9138803254693582)
+    assert entropy("L") == pytest.approx(7.063008716585465)
+    assert entropy("I") == pytest.approx(7.063008716585465)
+    assert entropy("F") == pytest.approx(7.063008716585465)
+    assert entropy("P") == pytest.approx(5.082506854662517)
+    assert entropy("RGB") == pytest.approx(8.821286587714319)
+    assert entropy("RGBA") == pytest.approx(7.42724306524488)
+    assert entropy("CMYK") == pytest.approx(7.4272430652448795)
+    assert entropy("YCbCr") == pytest.approx(7.698360534903628)

Tests/test_pdfparser.py

@@ -62,7 +62,7 @@ def test_parsing() -> None:
     assert PdfParser.get_value(b"(\\53a)", 0) == (b"\x2ba", 6)
     assert PdfParser.get_value(b"(\\1111)", 0) == (b"\x491", 7)
     assert PdfParser.get_value(b" 123 (", 0) == (123, 4)
-    assert round(abs(PdfParser.get_value(b" 123.4 %", 0)[0] - 123.4), 7) == 0
+    assert PdfParser.get_value(b" 123.4 %", 0)[0] == pytest.approx(123.4)
     assert PdfParser.get_value(b" 123.4 %", 0)[1] == 6
     with pytest.raises(PdfFormatError):
         PdfParser.get_value(b"]", 0)