Simplify test code (#9382)

updates:
- [github.com/astral-sh/ruff-pre-commit: v0.14.7 → v0.14.10](https://github.com/astral-sh/ruff-pre-commit/compare/v0.14.7...v0.14.10)
- [github.com/psf/black-pre-commit-mirror: 25.11.0 → 25.12.0](https://github.com/psf/black-pre-commit-mirror/compare/25.11.0...25.12.0)
- [github.com/pre-commit/mirrors-clang-format: v21.1.6 → v21.1.8](https://github.com/pre-commit/mirrors-clang-format/compare/v21.1.6...v21.1.8)
- [github.com/python-jsonschema/check-jsonschema: 0.35.0 → 0.36.0](https://github.com/python-jsonschema/check-jsonschema/compare/0.35.0...0.36.0)
- [github.com/zizmorcore/zizmor-pre-commit: v1.18.0 → v1.19.0](https://github.com/zizmorcore/zizmor-pre-commit/compare/v1.18.0...v1.19.0)
- [github.com/tox-dev/tox-ini-fmt: 1.7.0 → 1.7.1](https://github.com/tox-dev/tox-ini-fmt/compare/1.7.0...1.7.1)

.ci/requirements-mypy.txt

@@ -1,4 +1,4 @@
-mypy==1.19.0
+mypy==1.19.1
 arro3-compute
 arro3-core
 IceSpringPySideStubs-PyQt6
@@ -9,7 +9,6 @@ packaging
 pyarrow-stubs
 pybind11
 pytest
-sphinx
 types-atheris
 types-defusedxml
 types-olefile

.github/renovate.json

@@ -6,6 +6,7 @@
     "labels": [
         "Dependency"
     ],
+    "minimumReleaseAge": "7 days",
     "packageRules": [
         {
             "groupName": "github-actions",

.github/workflows/cifuzz.yml

@@ -44,13 +44,13 @@ jobs:
         language: python
         dry-run: false
     - name: Upload New Crash
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       if: failure() && steps.build.outcome == 'success'
       with:
         name: artifacts
         path: ./out/artifacts
     - name: Upload Legacy Crash
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       if: steps.run.outcome == 'success'
       with:
         name: crash

.github/workflows/docs.yml

@@ -49,7 +49,7 @@ jobs:
       run: python3 .github/workflows/system-info.py
 
     - name: Cache libimagequant
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       id: cache-libimagequant
       with:
         path: ~/cache-libimagequant

.github/workflows/lint.yml

@@ -23,7 +23,7 @@ jobs:
           persist-credentials: false
       - uses: actions/setup-python@v6
         with:
-          python-version: "3.10"
+          python-version: "3.x"
       - name: Install uv
         uses: astral-sh/setup-uv@v7
       - name: Lint

.github/workflows/test-windows.yml

@@ -112,7 +112,7 @@ jobs:
 
     - name: Cache build
       id: build-cache
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       with:
         path: winbuild\build
         key:
@@ -188,8 +188,9 @@ jobs:
     # trim ~150MB for each job
     - name: Optimize build cache
       if: steps.build-cache.outputs.cache-hit != 'true'
-      run: rmdir /S /Q winbuild\build\src
-      shell: cmd
+      run: |
+        rm -rf winbuild\build\src
+      shell: bash
 
     - name: Build Pillow
       run: |
@@ -206,9 +207,7 @@ jobs:
 
     - name: Test Pillow
       run: |
-        path %GITHUB_WORKSPACE%\winbuild\build\bin;%PATH%
         .ci\test.cmd
-      shell: cmd
 
     - name: Prepare to upload errors
       if: failure()
@@ -217,7 +216,7 @@ jobs:
       shell: bash
 
     - name: Upload errors
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       if: failure()
       with:
         name: errors

.github/workflows/test.yml

@@ -92,7 +92,7 @@ jobs:
 
     - name: Cache libimagequant
       if: startsWith(matrix.os, 'ubuntu')
-      uses: actions/cache@v4
+      uses: actions/cache@v5
       id: cache-libimagequant
       with:
         path: ~/cache-libimagequant
@@ -143,7 +143,7 @@ jobs:
         mkdir -p Tests/errors
 
     - name: Upload errors
-      uses: actions/upload-artifact@v5
+      uses: actions/upload-artifact@v6
       if: failure()
       with:
         name: errors

.github/workflows/wheels-dependencies.sh

@@ -267,7 +267,7 @@ function build {
 
     build_simple xcb-proto 1.17.0 https://xorg.freedesktop.org/archive/individual/proto
     if [[ -n "$IS_MACOS" ]]; then
-        build_simple xorgproto 2024.1 https://www.x.org/pub/individual/proto
+        build_simple xorgproto 2025.1 https://www.x.org/pub/individual/proto
         build_simple libXau 1.0.12 https://www.x.org/pub/individual/lib
         build_simple libpthread-stubs 0.5 https://xcb.freedesktop.org/dist
     else

.github/workflows/wheels.yml

@@ -134,7 +134,7 @@ jobs:
           CIBW_MANYLINUX_X86_64_IMAGE: ${{ matrix.manylinux }}
           MACOSX_DEPLOYMENT_TARGET: ${{ matrix.macosx_deployment_target }}
 
-      - uses: actions/upload-artifact@v5
+      - uses: actions/upload-artifact@v6
         with:
           name: dist-${{ matrix.name }}
           path: ./wheelhouse/*.whl
@@ -186,24 +186,18 @@ jobs:
 
       - name: Build wheels
         run: |
-          setlocal EnableDelayedExpansion
-          for %%f in (winbuild\build\license\*) do (
-            set x=%%~nf
-            rem Skip FriBiDi license, it is not included in the wheel.
-            set fribidi=!x:~0,7!
-            if NOT !fribidi!==fribidi (
-              rem Skip imagequant license, it is not included in the wheel.
-              set libimagequant=!x:~0,13!
-              if NOT !libimagequant!==libimagequant (
-                echo. >> LICENSE
-                echo ===== %%~nf ===== >> LICENSE
-                echo. >> LICENSE
-                type %%f >> LICENSE
-              )
-            )
-          )
-          call winbuild\\build\\build_env.cmd
-          %pythonLocation%\python.exe -m cibuildwheel . --output-dir wheelhouse
+          for f in winbuild/build/license/*; do
+            name=$(basename "${f%.*}")
+            # Skip FriBiDi license, it is not included in the wheel.
+            [[ $name == fribidi* ]] && continue
+            # Skip imagequant license, it is not included in the wheel.
+            [[ $name == libimagequant* ]] && continue
+            echo "" >> LICENSE
+            echo "===== $name =====" >> LICENSE
+            echo "" >> LICENSE
+            cat "$f" >> LICENSE
+          done
+          cmd //c "winbuild\\build\\build_env.cmd && $pythonLocation\\python.exe -m cibuildwheel . --output-dir wheelhouse"
         env:
           CIBW_ARCHS: ${{ matrix.cibw_arch }}
           CIBW_BEFORE_ALL: "{package}\\winbuild\\build\\build_dep_all.cmd"
@@ -217,16 +211,16 @@ jobs:
             -e CI -e GITHUB_ACTIONS
             mcr.microsoft.com/windows/servercore:ltsc2022
             powershell C:\pillow\.github\workflows\wheels-test.ps1 %CD%\..\venv-test'
-        shell: cmd
+        shell: bash
 
       - name: Upload wheels
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: dist-windows-${{ matrix.cibw_arch }}
           path: ./wheelhouse/*.whl
 
       - name: Upload fribidi.dll
-        uses: actions/upload-artifact@v5
+        uses: actions/upload-artifact@v6
         with:
           name: fribidi-windows-${{ matrix.cibw_arch }}
           path: winbuild\build\bin\fribidi*
@@ -246,7 +240,7 @@ jobs:
 
     - run: make sdist
 
-    - uses: actions/upload-artifact@v5
+    - uses: actions/upload-artifact@v6
       with:
         name: dist-sdist
         path: dist/*.tar.gz
@@ -256,7 +250,7 @@ jobs:
     runs-on: ubuntu-latest
     name: Count dists
     steps:
-      - uses: actions/download-artifact@v6
+      - uses: actions/download-artifact@v7
         with:
           pattern: dist-*
           path: dist
@@ -275,13 +269,13 @@ jobs:
     runs-on: ubuntu-latest
     name: Upload wheels to scientific-python-nightly-wheels
     steps:
-      - uses: actions/download-artifact@v6
+      - uses: actions/download-artifact@v7
         with:
           pattern: dist-!(sdist)*
           path: dist
           merge-multiple: true
       - name: Upload wheels to scientific-python-nightly-wheels
-        uses: scientific-python/upload-nightly-action@b36e8c0c10dbcfd2e05bf95f17ef8c14fd708dbf # 0.6.2
+        uses: scientific-python/upload-nightly-action@5748273c71e2d8d3a61f3a11a16421c8954f9ecf # 0.6.3
         with:
           artifacts_path: dist
           anaconda_nightly_upload_token: ${{ secrets.ANACONDA_ORG_UPLOAD_TOKEN }}
@@ -297,7 +291,7 @@ jobs:
     permissions:
       id-token: write
     steps:
-      - uses: actions/download-artifact@v6
+      - uses: actions/download-artifact@v7
         with:
           pattern: dist-*
           path: dist

.github/zizmor.yml

@@ -1,7 +1,5 @@
 # https://docs.zizmor.sh/configuration/
 rules:
-  obfuscation:
-    disable: true
   unpinned-uses:
     config:
       policies:

.pre-commit-config.yaml

@@ -1,12 +1,12 @@
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.14.7
+    rev: v0.14.10
     hooks:
       - id: ruff-check
         args: [--exit-non-zero-on-fix]
 
   - repo: https://github.com/psf/black-pre-commit-mirror
-    rev: 25.11.0
+    rev: 25.12.0
     hooks:
       - id: black
 
@@ -24,7 +24,7 @@ repos:
         exclude: (Makefile$|\.bat$|\.cmake$|\.eps$|\.fits$|\.gd$|\.opt$)
 
   - repo: https://github.com/pre-commit/mirrors-clang-format
-    rev: v21.1.6
+    rev: v21.1.8
     hooks:
       - id: clang-format
         types: [c]
@@ -51,14 +51,14 @@ repos:
         exclude: ^\.github/.*TEMPLATE|^Tests/(fonts|images)/
 
   - repo: https://github.com/python-jsonschema/check-jsonschema
-    rev: 0.35.0
+    rev: 0.36.0
     hooks:
       - id: check-github-workflows
       - id: check-readthedocs
       - id: check-renovate
 
   - repo: https://github.com/zizmorcore/zizmor-pre-commit
-    rev: v1.18.0
+    rev: v1.19.0
     hooks:
       - id: zizmor
 
@@ -76,10 +76,10 @@ repos:
     rev: v0.24.1
     hooks:
       - id: validate-pyproject
-        additional_dependencies: [tomli, trove-classifiers>=2024.10.12]
+        additional_dependencies: [trove-classifiers>=2024.10.12]
 
   - repo: https://github.com/tox-dev/tox-ini-fmt
-    rev: 1.7.0
+    rev: 1.7.1
     hooks:
       - id: tox-ini-fmt
 

Tests/test_file_psd.py

@@ -100,7 +100,7 @@ def test_seek_tell() -> None:
 
         im.seek(2)
         layer_number = im.tell()
-        assert layer_number == 2
+    assert layer_number == 2
 
 
 def test_seek_eoferror() -> None:
@@ -138,7 +138,7 @@ def test_icc_profile() -> None:
         assert "icc_profile" in im.info
 
         icc_profile = im.info["icc_profile"]
-        assert len(icc_profile) == 3144
+    assert len(icc_profile) == 3144
 
 
 def test_no_icc_profile() -> None:
@@ -158,17 +158,16 @@ def test_combined_larger_than_size() -> None:
 
 
 @pytest.mark.parametrize(
-    "test_file,raises",
+    "test_file",
     [
-        ("Tests/images/timeout-c8efc3fded6426986ba867a399791bae544f59bc.psd", OSError),
-        ("Tests/images/timeout-dedc7a4ebd856d79b4359bbcc79e8ef231ce38f6.psd", OSError),
+        "Tests/images/timeout-c8efc3fded6426986ba867a399791bae544f59bc.psd",
+        "Tests/images/timeout-dedc7a4ebd856d79b4359bbcc79e8ef231ce38f6.psd",
     ],
 )
-def test_crashes(test_file: str, raises: type[Exception]) -> None:
-    with open(test_file, "rb") as f:
-        with pytest.raises(raises):
-            with Image.open(f):
-                pass
+def test_crashes(test_file: str) -> None:
+    with pytest.raises(OSError):
+        with Image.open(test_file):
+            pass
 
 
 @pytest.mark.parametrize(
@@ -179,8 +178,7 @@ def test_crashes(test_file: str, raises: type[Exception]) -> None:
     ],
 )
 def test_layer_crashes(test_file: str) -> None:
-    with open(test_file, "rb") as f:
-        with Image.open(f) as im:
-            assert isinstance(im, PsdImagePlugin.PsdImageFile)
-            with pytest.raises(SyntaxError):
-                im.layers
+    with Image.open(test_file) as im:
+        assert isinstance(im, PsdImagePlugin.PsdImageFile)
+        with pytest.raises(SyntaxError):
+            im.layers

Tests/test_imagedraw.py

@@ -68,10 +68,22 @@ def test_sanity() -> None:
     draw.rectangle(list(range(4)))
 
 
-def test_valueerror() -> None:
+def test_new_color() -> None:
     with Image.open("Tests/images/chi.gif") as im:
         draw = ImageDraw.Draw(im)
+        assert im.palette is not None
+        assert len(im.palette.colors) == 249
+
+        # Test drawing a new color onto the palette
         draw.line((0, 0), fill=(0, 0, 0))
+        assert im.palette is not None
+        assert len(im.palette.colors) == 250
+        assert im.palette.dirty
+
+        # Test drawing another new color, now that the palette is dirty
+        draw.point((0, 0), fill=(1, 0, 0))
+        assert len(im.palette.colors) == 251
+        assert im.convert("RGB").getpixel((0, 0)) == (1, 0, 0)
 
 
 def test_mode_mismatch() -> None:

Tests/test_imagemorph.py

@@ -231,15 +231,15 @@ def test_negate() -> None:
 
 
 def test_incorrect_mode() -> None:
-    im = hopper()
     mop = ImageMorph.MorphOp(op_name="erosion8")
 
-    with pytest.raises(ValueError, match="Image mode must be 1 or L"):
-        mop.apply(im)
-    with pytest.raises(ValueError, match="Image mode must be 1 or L"):
-        mop.match(im)
-    with pytest.raises(ValueError, match="Image mode must be 1 or L"):
-        mop.get_on_pixels(im)
+    with hopper() as im:
+        with pytest.raises(ValueError, match="Image mode must be 1 or L"):
+            mop.apply(im)
+        with pytest.raises(ValueError, match="Image mode must be 1 or L"):
+            mop.match(im)
+        with pytest.raises(ValueError, match="Image mode must be 1 or L"):
+            mop.get_on_pixels(im)
 
 
 def test_add_patterns() -> None:

Tests/test_pyroma.py

@@ -6,10 +6,15 @@ import pytest
 
 from PIL import __version__
 
+TYPE_CHECKING = False
+
+if TYPE_CHECKING:
+    from importlib.metadata import PackageMetadata
+
 pyroma = pytest.importorskip("pyroma", reason="Pyroma not installed")
 
 
-def map_metadata_keys(md):
+def map_metadata_keys(md: PackageMetadata) -> dict[str, str | list[str] | None]:
     # Convert installed wheel metadata into canonical Core Metadata 2.4 format.
     # This was a utility method in pyroma 4.3.3; it was removed in 5.0.
     # This implementation is constructed from the relevant logic from
@@ -17,16 +22,16 @@ def map_metadata_keys(md):
     # upstream to Pyroma as https://github.com/regebro/pyroma/pull/116,
     # so it may be possible to simplify this test in future.
     data = {}
-    for key in set(md.keys()):
+    for key in set(md):
         value = md.get_all(key)
         key = pyroma.projectdata.normalize(key)
 
-        if len(value) == 1:
-            value = value[0]
-            if value.strip() == "UNKNOWN":
-                continue
-
-        data[key] = value
+        if value is not None and len(value) == 1:
+            first_value = value[0]
+            if first_value.strip() != "UNKNOWN":
+                data[key] = first_value
+        else:
+            data[key] = value
     return data
 
 

docs/dater.py

@@ -11,7 +11,7 @@ import subprocess
 
 TYPE_CHECKING = False
 if TYPE_CHECKING:
-    from sphinx.application import Sphinx
+    from typing import Any
 
 DOC_NAME_REGEX = re.compile(r"releasenotes/\d+\.\d+\.\d+")
 VERSION_TITLE_REGEX = re.compile(r"^(\d+\.\d+\.\d+)\n-+\n")
@@ -28,7 +28,7 @@ def get_date_for(git_version: str) -> str | None:
     return out.split()[0]
 
 
-def add_date(app: Sphinx, doc_name: str, source: list[str]) -> None:
+def add_date(app: Any, doc_name: str, source: list[str]) -> None:
     if DOC_NAME_REGEX.match(doc_name) and (m := VERSION_TITLE_REGEX.match(source[0])):
         old_title = m.group(1)
 
@@ -43,6 +43,6 @@ def add_date(app: Sphinx, doc_name: str, source: list[str]) -> None:
         source[0] = result
 
 
-def setup(app: Sphinx) -> dict[str, bool]:
+def setup(app: Any) -> dict[str, bool]:
     app.connect("source-read", add_date)
     return {"parallel_read_safe": True}

pyproject.toml

@@ -217,6 +217,7 @@ testpaths = [
 python_version = "3.10"
 pretty = true
 disallow_any_generics = true
+disallow_untyped_defs = true
 enable_error_code = "ignore-without-code"
 extra_checks = true
 follow_imports = "silent"

selftest.py

@@ -76,7 +76,7 @@ def testimage() -> None:
     ('R', 'G', 'B')
     >>> im.getbbox()
     (0, 0, 128, 128)
-    >>> len(im.getdata())
+    >>> len(im.get_flattened_data())
     16384
     >>> im.getextrema()
     ((0, 255), (0, 255), (0, 255))

setup.py

@@ -363,7 +363,6 @@ class pil_build_ext(build_ext):
             ("disable-platform-guessing", None, "Disable platform guessing"),
             ("debug", None, "Debug logging"),
         ]
-        + [("add-imaging-libs=", None, "Add libs to _imaging build")]
     )
 
     @staticmethod
@@ -374,7 +373,6 @@ class pil_build_ext(build_ext):
         self.disable_platform_guessing = self.check_configuration(
             "platform-guessing", "disable"
         )
-        self.add_imaging_libs = ""
         build_ext.initialize_options(self)
         for x in self.feature:
             setattr(self, f"disable_{x}", self.check_configuration(x, "disable"))
@@ -901,7 +899,6 @@ class pil_build_ext(build_ext):
         # core library
 
         libs: list[str | bool | None] = []
-        libs.extend(self.add_imaging_libs.split())
         defs: list[tuple[str, str | None]] = []
         if feature.get("tiff"):
             libs.append(feature.get("tiff"))

src/PIL/Image.py

@@ -892,7 +892,9 @@ class Image:
                 else:
                     self.im.putpalettealphas(self.info["transparency"])
                 self.palette.mode = "RGBA"
-            else:
+            elif self.palette.mode != mode:
+                # If the palette rawmode is different to the mode,
+                # then update the Python palette data
                 self.palette.palette = self.im.getpalette(
                     self.palette.mode, self.palette.mode
                 )

src/PIL/_version.py

@@ -1,4 +1,4 @@
 # Master version for Pillow
 from __future__ import annotations
 
-__version__ = "12.1.0"
+__version__ = "12.2.0.dev0"