Use ipython PrettyPrinter, rather than custom class

.appveyor.yml

@@ -51,7 +51,7 @@ build_script:
 
 test_script:
 - cd c:\pillow
-- '%PYTHON%\%EXECUTABLE% -m pip install pytest pytest-cov pytest-timeout defusedxml numpy olefile pyroma'
+- '%PYTHON%\%EXECUTABLE% -m pip install pytest pytest-cov pytest-timeout defusedxml ipython numpy olefile pyroma'
 - c:\"Program Files (x86)"\"Windows Kits"\10\Debuggers\x86\gflags.exe /p /enable %PYTHON%\%EXECUTABLE%
 - '%PYTHON%\%EXECUTABLE% -c "from PIL import Image"'
 - '%PYTHON%\%EXECUTABLE% -m pytest -vx --cov PIL --cov Tests --cov-report term --cov-report xml Tests'

.ci/install.sh

@@ -30,6 +30,7 @@ python3 -m pip install --upgrade pip
 python3 -m pip install --upgrade wheel
 python3 -m pip install coverage
 python3 -m pip install defusedxml
+python3 -m pip install ipython
 python3 -m pip install olefile
 python3 -m pip install -U pytest
 python3 -m pip install -U pytest-cov

.github/workflows/macos-install.sh

@@ -23,6 +23,7 @@ export PKG_CONFIG_PATH="/usr/local/opt/openblas/lib/pkgconfig"
 
 python3 -m pip install coverage
 python3 -m pip install defusedxml
+python3 -m pip install ipython
 python3 -m pip install olefile
 python3 -m pip install -U pytest
 python3 -m pip install -U pytest-cov

.github/workflows/test-cygwin.yml

@@ -74,6 +74,7 @@ jobs:
             perl
             python3${{ matrix.python-minor-version }}-cython
             python3${{ matrix.python-minor-version }}-devel
+            python3${{ matrix.python-minor-version }}-ipython
             python3${{ matrix.python-minor-version }}-numpy
             python3${{ matrix.python-minor-version }}-sip
             python3${{ matrix.python-minor-version }}-tkinter

Tests/test_image.py

@@ -42,6 +42,12 @@ try:
 except ImportError:
     ElementTree = None
 
+PrettyPrinter: type | None
+try:
+    from IPython.lib.pretty import PrettyPrinter
+except ImportError:
+    PrettyPrinter = None
+
 
 # Deprecation helper
 def helper_image_new(mode: str, size: tuple[int, int]) -> Image.Image:
@@ -91,16 +97,15 @@ class TestImage:
         # with pytest.raises(MemoryError):
         #   Image.new("L", (1000000, 1000000))
 
+    @pytest.mark.skipif(PrettyPrinter is None, reason="IPython is not installed")
     def test_repr_pretty(self) -> None:
-        class Pretty:
-            def text(self, text: str) -> None:
-                self.pretty_output = text
-
         im = Image.new("L", (100, 100))
 
-        p = Pretty()
+        output = io.StringIO()
+        assert PrettyPrinter is not None
+        p = PrettyPrinter(output)
         im._repr_pretty_(p, False)
-        assert p.pretty_output == "<PIL.Image.Image image mode=L size=100x100>"
+        assert output.getvalue() == "<PIL.Image.Image image mode=L size=100x100>"
 
     def test_open_formats(self) -> None:
         PNGFILE = "Tests/images/hopper.png"

src/PIL/Image.py

@@ -221,6 +221,8 @@ if TYPE_CHECKING:
     import mmap
     from xml.etree.ElementTree import Element
 
+    from IPython.lib.pretty import PrettyPrinter
+
     from . import ImageFile, ImageFilter, ImagePalette, TiffImagePlugin
     from ._typing import NumpyArray, StrOrBytesPath, TypeGuard
 ID: list[str] = []
@@ -677,7 +679,7 @@ class Image:
             id(self),
         )
 
-    def _repr_pretty_(self, p, cycle: bool) -> None:
+    def _repr_pretty_(self, p: PrettyPrinter, cycle: bool) -> None:
         """IPython plain text display support"""
 
         # Same as __repr__ but without unpredictable id(self),