Merge branch 'main' into init

.appveyor.yml

@@ -1,3 +1,10 @@
+skip_commits:
+  files:
+    - ".github/**/*"
+    - ".gitmodules"
+    - "docs/**/*"
+    - "wheels/**/*"
+
 version: '{build}'
 clone_folder: c:\pillow
 init:
@@ -6,6 +13,7 @@ init:
 # Uncomment previous line to get RDP access during the build.
 
 environment:
+  COVERAGE_CORE: sysmon
   EXECUTABLE: python.exe
   TEST_OPTIONS:
   DEPLOY: YES
@@ -26,7 +34,7 @@ install:
 - xcopy /S /Y c:\test-images-main\* c:\pillow\tests\images
 - curl -fsSL -o nasm-win64.zip https://raw.githubusercontent.com/python-pillow/pillow-depends/main/nasm-2.16.01-win64.zip
 - 7z x nasm-win64.zip -oc:\
-- choco install ghostscript --version=10.0.0.20230317
+- choco install ghostscript --version=10.3.0
 - path c:\nasm-2.16.01;C:\Program Files\gs\gs10.00.0\bin;%PATH%
 - cd c:\pillow\winbuild\
 - ps: |

.ci/requirements-cibw.txt

@@ -1 +1 @@
-cibuildwheel==2.16.5
+cibuildwheel==2.17.0

.ci/requirements-mypy.txt

@@ -0,0 +1 @@
+mypy==1.9.0

.coveragerc

@@ -10,6 +10,11 @@ exclude_also =
     if DEBUG:
     # Don't complain about compatibility code for missing optional dependencies
     except ImportError
+    if TYPE_CHECKING:
+    @abc.abstractmethod
+    # Empty bodies in protocols or abstract methods
+    ^\s*def [a-zA-Z0-9_]+\(.*\)(\s*->.*)?:\s*\.\.\.(\s*#.*)?$
+    ^\s*\.\.\.(\s*#.*)?$
 
 [run]
 omit =

.github/FUNDING.yml

@@ -1 +1 @@
-tidelift: "pypi/Pillow"
+tidelift: "pypi/pillow"

.github/ISSUE_TEMPLATE/ISSUE_REPORT.md

@@ -48,6 +48,21 @@ Thank you.
 * Python: 
 * Pillow: 
 
+```text
+Please paste here the output of running:
+
+python3 -m PIL.report
+or
+python3 -m PIL --report
+
+Or the output of the following Python code:
+
+from PIL import report
+# or
+from PIL import features
+features.pilinfo(supported_formats=False)
+```
+
 <!--
 Please include **code** that reproduces the issue and whenever possible, an **image** that demonstrates the issue. Please upload images to GitHub, not to third-party file hosting sites. If necessary, add the image to a zip or tar archive.
 

.github/workflows/docs.yml

@@ -7,10 +7,12 @@ on:
     paths:
       - ".github/workflows/docs.yml"
       - "docs/**"
+      - "src/PIL/**"
   pull_request:
     paths:
       - ".github/workflows/docs.yml"
       - "docs/**"
+      - "src/PIL/**"
   workflow_dispatch:
 
 permissions:

.github/workflows/release-drafter.yml

@@ -23,6 +23,6 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       # Drafts your next release notes as pull requests are merged into "main"
-      - uses: release-drafter/release-drafter@v5
+      - uses: release-drafter/release-drafter@v6
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}

.github/workflows/system-info.py

@@ -6,6 +6,7 @@ This sort of info is missing from GitHub Actions.
 Requested here:
 https://github.com/actions/virtual-environments/issues/79
 """
+
 from __future__ import annotations
 
 import os

.github/workflows/test-cygwin.yml

@@ -26,6 +26,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+env:
+  COVERAGE_CORE: sysmon
+
 jobs:
   build:
     runs-on: windows-latest
@@ -47,9 +50,8 @@ jobs:
         uses: actions/checkout@v4
 
       - name: Install Cygwin
-        uses: egor-tensin/setup-cygwin@v4
+        uses: cygwin/cygwin-install-action@v4
         with:
-          platform: x86_64
           packages: >
             gcc-g++
             ghostscript
@@ -69,7 +71,6 @@ jobs:
             make
             netpbm
             perl
-            python39=3.9.16-1
             python3${{ matrix.python-minor-version }}-cffi
             python3${{ matrix.python-minor-version }}-cython
             python3${{ matrix.python-minor-version }}-devel
@@ -81,27 +82,21 @@ jobs:
             zlib-devel
 
       - name: Add Lapack to PATH
-        uses: egor-tensin/cleanup-path@v3
+        uses: egor-tensin/cleanup-path@v4
         with:
           dirs: 'C:\cygwin\bin;C:\cygwin\lib\lapack'
 
       - name: Select Python version
         run: |
-          ln -sf c:/tools/cygwin/bin/python3.${{ matrix.python-minor-version }} c:/tools/cygwin/bin/python3
-
-      - name: Get latest NumPy version
-        id: latest-numpy
-        shell: bash.exe -eo pipefail -o igncr "{0}"
-        run: |
-          python3 -m pip list --outdated | grep numpy | sed -r 's/ +/ /g' | cut -d ' ' -f 3 | sed 's/^/version=/' >> $GITHUB_OUTPUT
+          ln -sf c:/cygwin/bin/python3.${{ matrix.python-minor-version }} c:/cygwin/bin/python3
 
       - name: pip cache
         uses: actions/cache@v4
         with:
           path: 'C:\cygwin\home\runneradmin\.cache\pip'
-          key: ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-numpy${{ steps.latest-numpy.outputs.version }}-${{ hashFiles('.ci/install.sh') }}
+          key: ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-${{ hashFiles('.ci/install.sh') }}
           restore-keys: |
-            ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-numpy${{ steps.latest-numpy.outputs.version }}-
+            ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-
 
       - name: Build system information
         run: |
@@ -111,11 +106,6 @@ jobs:
         run: |
           bash.exe .ci/install.sh
 
-      - name: Upgrade NumPy
-        shell: dash.exe -l "{0}"
-        run: |
-          python3 -m pip install -U "numpy<1.26"
-
       - name: Build
         shell: bash.exe -eo pipefail -o igncr "{0}"
         run: |
@@ -142,7 +132,7 @@ jobs:
           bash.exe .ci/after_success.sh
 
       - name: Upload coverage
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v3.1.5
         with:
           file: ./coverage.xml
           flags: GHA_Cygwin

.github/workflows/test-docker.yml

@@ -101,7 +101,7 @@ jobs:
         MATRIX_DOCKER: ${{ matrix.docker }}
 
     - name: Upload coverage
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v3.1.5
       with:
         flags: GHA_Docker
         name: ${{ matrix.docker }}

.github/workflows/test-mingw.yml

@@ -26,6 +26,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+env:
+  COVERAGE_CORE: sysmon
+
 jobs:
   build:
     runs-on: windows-latest
@@ -64,10 +67,10 @@ jobs:
               mingw-w64-x86_64-python3-cffi \
               mingw-w64-x86_64-python3-numpy \
               mingw-w64-x86_64-python3-olefile \
-              mingw-w64-x86_64-python3-pip \
               mingw-w64-x86_64-python3-setuptools \
               mingw-w64-x86_64-python-pyqt6
 
+          python3 -m ensurepip
           python3 -m pip install pyroma pytest pytest-cov pytest-timeout
 
           pushd depends && ./install_extra_test_images.sh && popd
@@ -82,7 +85,7 @@ jobs:
           python3 -m pytest -vx --cov PIL --cov Tests --cov-report term --cov-report xml Tests
 
       - name: Upload coverage
-        uses: codecov/codecov-action@v3
+        uses: codecov/codecov-action@v3.1.5
         with:
           file: ./coverage.xml
           flags: GHA_Windows

.github/workflows/test-windows.yml

@@ -26,6 +26,9 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+env:
+  COVERAGE_CORE: sysmon
+
 jobs:
   build:
     runs-on: windows-latest
@@ -66,8 +69,16 @@ jobs:
     - name: Print build system information
       run: python3 .github/workflows/system-info.py
 
-    - name: python3 -m pip install pytest pytest-cov pytest-timeout defusedxml olefile pyroma
-      run: python3 -m pip install pytest pytest-cov pytest-timeout defusedxml olefile pyroma
+    - name: Install Python dependencies
+      run: >
+        python3 -m pip install
+        coverage>=7.4.2
+        defusedxml
+        olefile
+        pyroma
+        pytest
+        pytest-cov
+        pytest-timeout
 
     - name: Install dependencies
       id: install
@@ -75,7 +86,7 @@ jobs:
         choco install nasm --no-progress
         echo "C:\Program Files\NASM" >> $env:GITHUB_PATH
 
-        choco install ghostscript --version=10.0.0.20230317 --no-progress
+        choco install ghostscript --version=10.3.0 --no-progress
         echo "C:\Program Files\gs\gs10.00.0\bin" >> $env:GITHUB_PATH
 
         # Install extra test images
@@ -202,7 +213,7 @@ jobs:
       shell: pwsh
 
     - name: Upload coverage
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v3.1.5
       with:
         file: ./coverage.xml
         flags: GHA_Windows

.github/workflows/test.yml

@@ -27,6 +27,7 @@ concurrency:
   cancel-in-progress: true
 
 env:
+  COVERAGE_CORE: sysmon
   FORCE_COLOR: 1
 
 jobs:
@@ -149,7 +150,7 @@ jobs:
         .ci/after_success.sh
 
     - name: Upload coverage
-      uses: codecov/codecov-action@v3
+      uses: codecov/codecov-action@v3.1.5
       with:
         flags: ${{ matrix.os == 'ubuntu-latest' && 'GHA_Ubuntu' || 'GHA_macOS' }}
         name: ${{ matrix.os }} Python ${{ matrix.python-version }}

.github/workflows/wheels-dependencies.sh

@@ -16,31 +16,31 @@ ARCHIVE_SDIR=pillow-depends-main
 
 # Package versions for fresh source builds
 FREETYPE_VERSION=2.13.2
-HARFBUZZ_VERSION=8.3.0
-LIBPNG_VERSION=1.6.40
-JPEGTURBO_VERSION=3.0.1
-OPENJPEG_VERSION=2.5.0
+HARFBUZZ_VERSION=8.4.0
+LIBPNG_VERSION=1.6.43
+JPEGTURBO_VERSION=3.0.2
+OPENJPEG_VERSION=2.5.2
 XZ_VERSION=5.4.5
 TIFF_VERSION=4.6.0
 LCMS2_VERSION=2.16
 if [[ -n "$IS_MACOS" ]]; then
-    GIFLIB_VERSION=5.1.4
+    GIFLIB_VERSION=5.2.2
 else
     GIFLIB_VERSION=5.2.1
 fi
 if [[ -n "$IS_MACOS" ]] || [[ "$MB_ML_VER" != 2014 ]]; then
-    ZLIB_VERSION=1.3
+    ZLIB_VERSION=1.3.1
 else
     ZLIB_VERSION=1.2.8
 fi
 LIBWEBP_VERSION=1.3.2
 BZIP2_VERSION=1.0.8
-LIBXCB_VERSION=1.16
+LIBXCB_VERSION=1.16.1
 BROTLI_VERSION=1.1.0
 
 if [[ -n "$IS_MACOS" ]] && [[ "$CIBW_ARCHS" == "x86_64" ]]; then
     function build_openjpeg {
-        local out_dir=$(fetch_unpack https://github.com/uclouvain/openjpeg/archive/v${OPENJPEG_VERSION}.tar.gz openjpeg-2.5.0.tar.gz)
+        local out_dir=$(fetch_unpack https://github.com/uclouvain/openjpeg/archive/v${OPENJPEG_VERSION}.tar.gz openjpeg-${OPENJPEG_VERSION}.tar.gz)
         (cd $out_dir \
             && cmake -DCMAKE_INSTALL_PREFIX=$BUILD_PREFIX -DCMAKE_INSTALL_NAME_DIR=$BUILD_PREFIX/lib . \
             && make install)
@@ -62,7 +62,7 @@ function build_brotli {
 
 function build {
     if [[ -n "$IS_MACOS" ]] && [[ "$CIBW_ARCHS" == "arm64" ]]; then
-        export BUILD_PREFIX="/usr/local"
+        sudo chown -R runner /usr/local
     fi
     build_xz
     if [ -z "$IS_ALPINE" ] && [ -z "$IS_MACOS" ]; then
@@ -72,13 +72,11 @@ function build {
 
     build_simple xcb-proto 1.16.0 https://xorg.freedesktop.org/archive/individual/proto
     if [ -n "$IS_MACOS" ]; then
+        build_simple xorgproto 2024.1 https://www.x.org/pub/individual/proto
+        build_simple libXau 1.0.11 https://www.x.org/pub/individual/lib
+        build_simple libpthread-stubs 0.5 https://xcb.freedesktop.org/dist
         if [[ "$CIBW_ARCHS" == "arm64" ]]; then
-            build_simple xorgproto 2023.2 https://www.x.org/pub/individual/proto
-            build_simple libXau 1.0.11 https://www.x.org/pub/individual/lib
-            build_simple libpthread-stubs 0.5 https://xcb.freedesktop.org/dist
-            if [ -f /Library/Frameworks/Python.framework/Versions/Current/share/pkgconfig/xcb-proto.pc ]; then
-                cp /Library/Frameworks/Python.framework/Versions/Current/share/pkgconfig/xcb-proto.pc /Library/Frameworks/Python.framework/Versions/Current/lib/pkgconfig/xcb-proto.pc
-            fi
+            cp /usr/local/share/pkgconfig/xcb-proto.pc /usr/local/lib/pkgconfig
         fi
     else
         sed s/\${pc_sysrootdir\}// /usr/local/share/pkgconfig/xcb-proto.pc > /usr/local/lib/pkgconfig/xcb-proto.pc
@@ -89,12 +87,10 @@ function build {
     build_tiff
     build_libpng
     build_lcms2
-    if [[ -n "$IS_MACOS" ]] && [[ "$CIBW_ARCHS" == "arm64" ]]; then
-        for dylib in libjpeg.dylib libtiff.dylib liblcms2.dylib; do
-            cp $BUILD_PREFIX/lib/$dylib /opt/arm64-builds/lib
-        done
-    fi
     build_openjpeg
+    if [ -f /usr/local/lib64/libopenjp2.so ]; then
+        cp /usr/local/lib64/libopenjp2.so /usr/local/lib
+    fi
 
     ORIGINAL_CFLAGS=$CFLAGS
     CFLAGS="$CFLAGS -O3 -DNDEBUG"
@@ -130,14 +126,19 @@ curl -fsSL -o pillow-depends-main.zip https://github.com/python-pillow/pillow-de
 untar pillow-depends-main.zip
 
 if [[ -n "$IS_MACOS" ]]; then
-  # webp, libtiff, libxcb cause a conflict with building webp, libtiff, libxcb
-  # libxdmcp causes an issue on macOS < 11
-  # if php is installed, brew tries to reinstall these after installing openblas
+  # libtiff and libxcb cause a conflict with building libtiff and libxcb
+  # libxau and libxdmcp cause an issue on macOS < 11
   # remove cairo to fix building harfbuzz on arm64
   # remove lcms2 and libpng to fix building openjpeg on arm64
-  # remove zstd to avoid inclusion on x86_64
+  # remove jpeg-turbo to avoid inclusion on arm64
+  # remove webp and zstd to avoid inclusion on x86_64
   # curl from brew requires zstd, use system curl
-  brew remove --ignore-dependencies webp libpng libtiff libxcb libxdmcp curl php cairo lcms2 ghostscript zstd
+  brew remove --ignore-dependencies libpng libtiff libxcb libxau libxdmcp curl cairo lcms2 zstd
+  if [[ "$CIBW_ARCHS" == "arm64" ]]; then
+    brew remove --ignore-dependencies jpeg-turbo
+  else
+    brew remove --ignore-dependencies webp
+  fi
 
   brew install pkg-config
 fi

.github/workflows/wheels-test.sh

@@ -4,6 +4,9 @@ set -e
 if [[ "$OSTYPE" == "darwin"* ]]; then
     brew install fribidi
     export PKG_CONFIG_PATH="/usr/local/opt/openblas/lib/pkgconfig"
+    if [ -f /opt/homebrew/lib/libfribidi.dylib ]; then
+        sudo cp /opt/homebrew/lib/libfribidi.dylib /usr/local/lib
+    fi
 elif [ "${AUDITWHEEL_POLICY::9}" == "musllinux" ]; then
     apk add curl fribidi
 else

.github/workflows/wheels.yml

@@ -5,6 +5,7 @@ on:
     paths:
       - ".ci/requirements-cibw.txt"
       - ".github/workflows/wheel*"
+      - "setup.py"
       - "wheels/*"
       - "winbuild/build_prepare.py"
       - "winbuild/fribidi.cmake"
@@ -14,6 +15,7 @@ on:
     paths:
       - ".ci/requirements-cibw.txt"
       - ".github/workflows/wheel*"
+      - "setup.py"
       - "wheels/*"
       - "winbuild/build_prepare.py"
       - "winbuild/fribidi.cmake"
@@ -99,7 +101,7 @@ jobs:
             cibw_arch: x86_64
             macosx_deployment_target: "10.10"
           - name: "macOS arm64"
-            os: macos-latest
+            os: macos-14
             cibw_arch: arm64
             macosx_deployment_target: "11.0"
           - name: "manylinux2014 and musllinux x86_64"
@@ -132,7 +134,7 @@ jobs:
           CIBW_MANYLINUX_PYPY_X86_64_IMAGE: ${{ matrix.manylinux }}
           CIBW_MANYLINUX_X86_64_IMAGE: ${{ matrix.manylinux }}
           CIBW_SKIP: pp38-*
-          CIBW_TEST_SKIP: "*-macosx_arm64"
+          CIBW_TEST_SKIP: cp38-macosx_arm64
           MACOSX_DEPLOYMENT_TARGET: ${{ matrix.macosx_deployment_target }}
 
       - uses: actions/upload-artifact@v4

.pre-commit-config.yaml

@@ -1,24 +1,24 @@
 repos:
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.1.9
+    rev: v0.3.4
     hooks:
       - id: ruff
-        args: [--fix, --exit-non-zero-on-fix]
+        args: [--exit-non-zero-on-fix]
 
   - repo: https://github.com/psf/black-pre-commit-mirror
-    rev: 23.12.1
+    rev: 24.3.0
     hooks:
       - id: black
 
   - repo: https://github.com/PyCQA/bandit
-    rev: 1.7.6
+    rev: 1.7.8
     hooks:
     - id: bandit
       args: [--severity-level=high]
       files: ^src/
 
   - repo: https://github.com/Lucas-C/pre-commit-hooks
-    rev: v1.5.4
+    rev: v1.5.5
     hooks:
       - id: remove-tabs
         exclude: (Makefile$|\.bat$|\.cmake$|\.eps$|\.fits$|\.gd$|\.opt$)
@@ -42,18 +42,25 @@ repos:
       - id: trailing-whitespace
         exclude: ^.github/.*TEMPLATE|^Tests/(fonts|images)/
 
+  - repo: https://github.com/python-jsonschema/check-jsonschema
+    rev: 0.28.1
+    hooks:
+      - id: check-github-workflows
+      - id: check-readthedocs
+      - id: check-renovate
+
   - repo: https://github.com/sphinx-contrib/sphinx-lint
     rev: v0.9.1
     hooks:
       - id: sphinx-lint
 
   - repo: https://github.com/tox-dev/pyproject-fmt
-    rev: 1.5.3
+    rev: 1.7.0
     hooks:
       - id: pyproject-fmt
 
   - repo: https://github.com/abravalheri/validate-pyproject
-    rev: v0.15
+    rev: v0.16
     hooks:
       - id: validate-pyproject
 
@@ -62,5 +69,10 @@ repos:
     hooks:
       - id: tox-ini-fmt
 
+  - repo: meta
+    hooks:
+      - id: check-hooks-apply
+      - id: check-useless-excludes
+
 ci:
   autoupdate_schedule: monthly

CHANGES.rst

@@ -2,9 +2,120 @@
 Changelog (Pillow)
 ==================
 
-10.3.0 (unreleased)
+10.3.0 (2024-04-01)
 -------------------
 
+- CVE-2024-28219: Use ``strncpy`` to avoid buffer overflow #7928
+  [radarhere, hugovk]
+
+- Deprecate ``eval()``, replacing it with ``lambda_eval()`` and ``unsafe_eval()`` #7927
+  [radarhere, hugovk]
+
+- Raise ``ValueError`` if seeking to greater than offset-sized integer in TIFF #7883
+  [radarhere]
+
+- Add ``--report`` argument to ``__main__.py`` to omit supported formats #7818
+  [nulano, radarhere, hugovk]
+
+- Added RGB to I;16, I;16L, I;16B and I;16N conversion #7918, #7920
+  [radarhere]
+
+- Fix editable installation with custom build backend and configuration options #7658
+  [nulano, radarhere]
+
+- Fix putdata() for I;16N on big-endian #7209
+  [Yay295, hugovk, radarhere]
+
+- Determine MPO size from markers, not EXIF data #7884
+  [radarhere]
+
+- Improved conversion from RGB to RGBa, LA and La #7888
+  [radarhere]
+
+- Support FITS images with GZIP_1 compression #7894
+  [radarhere]
+
+- Use I;16 mode for 9-bit JPEG 2000 images #7900
+  [scaramallion, radarhere]
+
+- Raise ValueError if kmeans is negative #7891
+  [radarhere]
+
+- Remove TIFF tag OSUBFILETYPE when saving using libtiff #7893
+  [radarhere]
+
+- Raise ValueError for negative values when loading P1-P3 PPM images #7882
+  [radarhere]
+
+- Added reading of JPEG2000 palettes #7870
+  [radarhere]
+
+- Added alpha_quality argument when saving WebP images #7872
+  [radarhere]
+
+- Fixed joined corners for ImageDraw rounded_rectangle() non-integer dimensions #7881
+  [radarhere]
+
+- Stop reading EPS image at EOF marker #7753
+  [radarhere]
+
+- PSD layer co-ordinates may be negative #7706
+  [radarhere]
+
+- Use subprocess with CREATE_NO_WINDOW flag in ImageShow WindowsViewer #7791
+  [radarhere]
+
+- When saving GIF frame that restores to background color, do not fill identical pixels #7788
+  [radarhere]
+
+- Fixed reading PNG iCCP compression method #7823
+  [radarhere]
+
+- Allow writing IFDRational to UNDEFINED tag #7840
+  [radarhere]
+
+- Fix logged tag name when loading Exif data #7842
+  [radarhere]
+
+- Use maximum frame size in IHDR chunk when saving APNG images #7821
+  [radarhere]
+
+- Prevent opening P TGA images without a palette #7797
+  [radarhere]
+
+- Use palette when loading ICO images #7798
+  [radarhere]
+
+- Use consistent arguments for load_read and load_seek #7713
+  [radarhere]
+
+- Turn off nullability warnings for macOS SDK #7827
+  [radarhere]
+
+- Fix shift-sign issue in Convert.c #7838
+  [r-barnes, radarhere]
+
+- Open 16-bit grayscale PNGs as I;16 #7849
+  [radarhere]
+
+- Handle truncated chunks at the end of PNG images #7709
+  [lajiyuan, radarhere]
+
+- Match mask size to pasted image size in GifImagePlugin #7779
+  [radarhere]
+
+- Release GIL while calling ``WebPAnimDecoderGetNext`` #7782
+  [evanmiller, radarhere]
+
+- Fixed reading FLI/FLC images with a prefix chunk #7804
+  [twolife]
+
+- Update wl-paste handling and return None for some errors in grabclipboard() on Linux #7745
+  [nik012003, radarhere]
+
+- Remove execute bit from ``setup.py`` #7760
+  [hugovk]
+
 - Do not support using test-image-results to upload images after test failures #7739
   [radarhere]
 
@@ -4235,7 +4346,7 @@ Changelog (Pillow)
 - Documentation changes, URL update, transpose, release checklist
   [radarhere]
 
-- Fixed saving to nonexistant files specified by pathlib.Path objects #1748 (fixes #1747)
+- Fixed saving to nonexistent files specified by pathlib.Path objects #1748 (fixes #1747)
   [radarhere]
 
 - Round Image.crop arguments to the nearest integer #1745 (fixes #1744)
@@ -7446,7 +7557,7 @@ The test suite includes 400 individual tests.
 - A handbook is available (distributed separately).
 
 - The coordinate system is changed so that (0,0) is now located
-  in the upper left corner.  This is in compliancy with ISO 12087
+  in the upper left corner.  This is in compliance with ISO 12087
   and 90% of all other image processing and graphics libraries.
 
 - Modes "1" (bilevel) and "P" (palette) have been introduced.  Note

LICENSE

@@ -1,11 +1,11 @@
 The Python Imaging Library (PIL) is
 
     Copyright © 1997-2011 by Secret Labs AB
-    Copyright © 1995-2011 by Fredrik Lundh
+    Copyright © 1995-2011 by Fredrik Lundh and contributors
 
 Pillow is the friendly PIL fork. It is
 
-    Copyright © 2010-2024 by Jeffrey A. Clark (Alex) and contributors.
+    Copyright © 2010-2024 by Jeffrey A. Clark and contributors
 
 Like PIL, Pillow is licensed under the open source HPND License:
 

README.md

@@ -6,9 +6,9 @@
 
 ## Python Imaging Library (Fork)
 
-Pillow is the friendly PIL fork by [Jeffrey A. Clark (Alex) and
+Pillow is the friendly PIL fork by [Jeffrey A. Clark and
 contributors](https://github.com/python-pillow/Pillow/graphs/contributors).
-PIL is the Python Imaging Library by Fredrik Lundh and Contributors.
+PIL is the Python Imaging Library by Fredrik Lundh and contributors.
 As of 2019, Pillow development is
 [supported by Tidelift](https://tidelift.com/subscription/pkg/pypi-pillow?utm_source=pypi-pillow&utm_medium=readme&utm_campaign=enterprise).
 
@@ -64,7 +64,7 @@ As of 2019, Pillow development is
                 src="https://zenodo.org/badge/17549/python-pillow/Pillow.svg"></a>
             <a href="https://tidelift.com/subscription/pkg/pypi-pillow?utm_source=pypi-pillow&utm_medium=badge"><img
                 alt="Tidelift"
-                src="https://tidelift.com/badges/package/pypi/Pillow?style=flat"></a>
+                src="https://tidelift.com/badges/package/pypi/pillow?style=flat"></a>
             <a href="https://pypi.org/project/pillow/"><img
                 alt="Newest PyPI version"
                 src="https://img.shields.io/pypi/v/pillow.svg"></a>
@@ -82,9 +82,6 @@ As of 2019, Pillow development is
             <a href="https://gitter.im/python-pillow/Pillow?utm_source=badge&utm_medium=badge&utm_campaign=pr-badge&utm_content=badge"><img
                 alt="Join the chat at https://gitter.im/python-pillow/Pillow"
                 src="https://badges.gitter.im/python-pillow/Pillow.svg"></a>
-            <a href="https://twitter.com/PythonPillow"><img
-                alt="Follow on https://twitter.com/PythonPillow"
-                src="https://img.shields.io/badge/tweet-on%20Twitter-00aced.svg"></a>
             <a href="https://fosstodon.org/@pillow"><img
                 alt="Follow on https://fosstodon.org/@pillow"
                 src="https://img.shields.io/badge/publish-on%20Mastodon-595aff.svg"

RELEASING.md

@@ -86,7 +86,7 @@ Released as needed privately to individual vendors for critical security-related
 
 ## Publicize Release
 
-* [ ] Announce release availability via [Twitter](https://twitter.com/pythonpillow) and [Mastodon](https://fosstodon.org/@pillow) e.g. https://twitter.com/PythonPillow/status/1013789184354603010
+* [ ] Announce release availability via [Mastodon](https://fosstodon.org/@pillow) e.g. https://fosstodon.org/@pillow/110639450470725321
 
 ## Documentation
 

Tests/bench_cffi_access.py

@@ -32,9 +32,8 @@ def timer(func, label, *args) -> None:
             break
     endtime = time.time()
     print(
-        "{}: completed {} iterations in {:.4f}s, {:.6f}s per iteration".format(
-            label, x + 1, endtime - starttime, (endtime - starttime) / (x + 1.0)
-        )
+        f"{label}: completed {x + 1} iterations in {endtime - starttime:.4f}s, "
+        f"{(endtime - starttime) / (x + 1.0):.6f}s per iteration"
     )
 
 

Tests/check_imaging_leaks.py

@@ -23,7 +23,10 @@ def _get_mem_usage() -> float:
 
 
 def _test_leak(
-    min_iterations: int, max_iterations: int, fn: Callable[..., None], *args: Any
+    min_iterations: int,
+    max_iterations: int,
+    fn: Callable[..., Image.Image | None],
+    *args: Any,
 ) -> None:
     mem_limit = None
     for i in range(max_iterations):

Tests/check_png_dos.py

@@ -17,6 +17,7 @@ def test_ignore_dos_text() -> None:
     finally:
         ImageFile.LOAD_TRUNCATED_IMAGES = False
 
+    assert isinstance(im, PngImagePlugin.PngImageFile)
     for s in im.text.values():
         assert len(s) < 1024 * 1024, "Text chunk larger than 1M"
 
@@ -32,6 +33,7 @@ def test_dos_text() -> None:
         assert msg, "Decompressed Data Too Large"
         return
 
+    assert isinstance(im, PngImagePlugin.PngImageFile)
     for s in im.text.values():
         assert len(s) < 1024 * 1024, "Text chunk larger than 1M"
 
@@ -57,6 +59,7 @@ def test_dos_total_memory() -> None:
         return
 
     total_len = 0
+    assert isinstance(im2, PngImagePlugin.PngImageFile)
     for txt in im2.text.values():
         total_len += len(txt)
     assert total_len < 64 * 1024 * 1024, "Total text chunks greater than 64M"

Tests/helper.py

@@ -1,6 +1,7 @@
 """
 Helper functions.
 """
+
 from __future__ import annotations
 
 import logging
@@ -10,6 +11,7 @@ import subprocess
 import sys
 import sysconfig
 import tempfile
+from functools import lru_cache
 from io import BytesIO
 from typing import Any, Callable, Sequence
 
@@ -113,7 +115,9 @@ def assert_image_similar(
 
     diff = 0
     for ach, bch in zip(a.split(), b.split()):
-        chdiff = ImageMath.eval("abs(a - b)", a=ach, b=bch).convert("L")
+        chdiff = ImageMath.lambda_eval(
+            lambda args: abs(args["a"] - args["b"]), a=ach, b=bch
+        ).convert("L")
         diff += sum(i * num for i, num in enumerate(chdiff.histogram()))
 
     ave_diff = diff / (a.size[0] * a.size[1])
@@ -243,31 +247,33 @@ def fromstring(data: bytes) -> Image.Image:
     return Image.open(BytesIO(data))
 
 
-def tostring(im: Image.Image, string_format: str, **options: dict[str, Any]) -> bytes:
+def tostring(im: Image.Image, string_format: str, **options: Any) -> bytes:
     out = BytesIO()
     im.save(out, string_format, **options)
     return out.getvalue()
 
 
-def hopper(mode: str | None = None, cache: dict[str, Image.Image] = {}) -> Image.Image:
+def hopper(mode: str | None = None) -> Image.Image:
+    # Use caching to reduce reading from disk, but return a copy
+    # so that the cached image isn't modified by the tests
+    # (for fast, isolated, repeatable tests).
+
     if mode is None:
         # Always return fresh not-yet-loaded version of image.
-        # Operations on not-yet-loaded images is separate class of errors
-        # what we should catch.
+        # Operations on not-yet-loaded images are a separate class of errors
+        # that we should catch.
         return Image.open("Tests/images/hopper.ppm")
-    # Use caching to reduce reading from disk but so an original copy is
-    # returned each time and the cached image isn't modified by tests
-    # (for fast, isolated, repeatable tests).
-    im = cache.get(mode)
-    if im is None:
-        if mode == "F":
-            im = hopper("L").convert(mode)
-        elif mode[:4] == "I;16":
-            im = hopper("I").convert(mode)
-        else:
-            im = hopper().convert(mode)
-        cache[mode] = im
-    return im.copy()
+
+    return _cached_hopper(mode).copy()
+
+
+@lru_cache
+def _cached_hopper(mode: str) -> Image.Image:
+    if mode == "F":
+        im = hopper("L")
+    else:
+        im = hopper()
+    return im.convert(mode)
 
 
 def djpeg_available() -> bool:
@@ -350,7 +356,7 @@ def is_mingw() -> bool:
 
 
 class CachedProperty:
-    def __init__(self, func: Callable[[Any], None]) -> None:
+    def __init__(self, func: Callable[[Any], Any]) -> None:
         self.func = func
 
     def __get__(self, instance: Any, cls: type[Any] | None = None) -> Any:

Tests/oss-fuzz/test_fuzzers.py

@@ -7,7 +7,7 @@ import fuzzers
 import packaging
 import pytest
 
-from PIL import Image, features
+from PIL import Image, UnidentifiedImageError, features
 from Tests.helper import skip_unless_feature
 
 if sys.platform.startswith("win32"):
@@ -43,7 +43,7 @@ def test_fuzz_images(path: str) -> None:
     except (
         Image.DecompressionBombError,
         Image.DecompressionBombWarning,
-        Image.UnidentifiedImageError,
+        UnidentifiedImageError,
     ):
         # Known Image.* exceptions
         assert True

Tests/test_bmp_reference.py

@@ -10,7 +10,7 @@ from .helper import assert_image_similar
 base = os.path.join("Tests", "images", "bmp")
 
 
-def get_files(d, ext: str = ".bmp"):
+def get_files(d: str, ext: str = ".bmp") -> list[str]:
     return [
         os.path.join(base, d, f) for f in os.listdir(os.path.join(base, d)) if ext in f
     ]
@@ -29,7 +29,7 @@ def test_bad() -> None:
                 pass
 
 
-def test_questionable():
+def test_questionable() -> None:
     """These shouldn't crash/dos, but it's not well defined that these
     are in spec"""
     supported = [
@@ -80,7 +80,7 @@ def test_good() -> None:
         "rgb32bf.bmp": "rgb24.png",
     }
 
-    def get_compare(f):
+    def get_compare(f: str) -> str:
         name = os.path.split(f)[1]
         if name in file_map:
             return os.path.join(base, "html", file_map[name])

Tests/test_box_blur.py

@@ -23,11 +23,11 @@ def test_imageops_box_blur() -> None:
     assert isinstance(i, Image.Image)
 
 
-def box_blur(image, radius: int = 1, n: int = 1):
+def box_blur(image: Image.Image, radius: float = 1, n: int = 1) -> Image.Image:
     return image._new(image.im.box_blur((radius, radius), n))
 
 
-def assert_image(im, data, delta: int = 0) -> None:
+def assert_image(im: Image.Image, data: list[list[int]], delta: int = 0) -> None:
     it = iter(im.getdata())
     for data_row in data:
         im_row = [next(it) for _ in range(im.size[0])]
@@ -37,7 +37,13 @@ def assert_image(im, data, delta: int = 0) -> None:
         next(it)
 
 
-def assert_blur(im, radius, data, passes: int = 1, delta: int = 0) -> None:
+def assert_blur(
+    im: Image.Image,
+    radius: float,
+    data: list[list[int]],
+    passes: int = 1,
+    delta: int = 0,
+) -> None:
     # check grayscale image
     assert_image(box_blur(im, radius, passes), data, delta)
     rgba = Image.merge("RGBA", (im, im, im, im))

Tests/test_color_lut.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from array import array
+from types import ModuleType
 
 import pytest
 
@@ -8,6 +9,7 @@ from PIL import Image, ImageFilter
 
 from .helper import assert_image_equal
 
+numpy: ModuleType | None
 try:
     import numpy
 except ImportError:
@@ -15,7 +17,9 @@ except ImportError:
 
 
 class TestColorLut3DCoreAPI:
-    def generate_identity_table(self, channels, size):
+    def generate_identity_table(
+        self, channels: int, size: int | tuple[int, int, int]
+    ) -> tuple[int, int, int, int, list[float]]:
         if isinstance(size, tuple):
             size_1d, size_2d, size_3d = size
         else:
@@ -395,6 +399,7 @@ class TestColorLut3DFilter:
 
     @pytest.mark.skipif(numpy is None, reason="NumPy not installed")
     def test_numpy_sources(self) -> None:
+        assert numpy is not None
         table = numpy.ones((5, 6, 7, 3), dtype=numpy.float16)
         with pytest.raises(ValueError, match="should have either channels"):
             lut = ImageFilter.Color3DLUT((5, 6, 7), table)
@@ -428,6 +433,7 @@ class TestColorLut3DFilter:
 
     @pytest.mark.skipif(numpy is None, reason="NumPy not installed")
     def test_numpy_formats(self) -> None:
+        assert numpy is not None
         g = Image.linear_gradient("L")
         im = Image.merge(
             "RGB",

Tests/test_core_resources.py

@@ -187,6 +187,6 @@ class TestEnvVars:
             {"PILLOW_BLOCKS_MAX": "wat"},
         ),
     )
-    def test_warnings(self, var) -> None:
+    def test_warnings(self, var: dict[str, str]) -> None:
         with pytest.warns(UserWarning):
             Image._apply_env_variables(var)

Tests/test_deprecate.py

@@ -20,7 +20,7 @@ from PIL import _deprecate
         ),
     ],
 )
-def test_version(version, expected) -> None:
+def test_version(version: int | None, expected: str) -> None:
     with pytest.warns(DeprecationWarning, match=expected):
         _deprecate.deprecate("Old thing", version, "new thing")
 
@@ -46,7 +46,7 @@ def test_unknown_version() -> None:
         ),
     ],
 )
-def test_old_version(deprecated, plural, expected) -> None:
+def test_old_version(deprecated: str, plural: bool, expected: str) -> None:
     expected = r""
     with pytest.raises(RuntimeError, match=expected):
         _deprecate.deprecate(deprecated, 1, plural=plural)
@@ -76,7 +76,7 @@ def test_replacement_and_action() -> None:
         "Upgrade to new thing.",
     ],
 )
-def test_action(action) -> None:
+def test_action(action: str) -> None:
     expected = (
         r"Old thing is deprecated and will be removed in Pillow 11 \(2024-10-15\)\. "
         r"Upgrade to new thing\."

Tests/test_features.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 import io
 import re
+from typing import Callable
 
 import pytest
 
@@ -29,7 +30,7 @@ def test_version() -> None:
     # Check the correctness of the convenience function
     # and the format of version numbers
 
-    def test(name, function) -> None:
+    def test(name: str, function: Callable[[str], bool]) -> None:
         version = features.version(name)
         if not features.check(name):
             assert version is None
@@ -73,12 +74,12 @@ def test_libimagequant_version() -> None:
 
 
 @pytest.mark.parametrize("feature", features.modules)
-def test_check_modules(feature) -> None:
+def test_check_modules(feature: str) -> None:
     assert features.check_module(feature) in [True, False]
 
 
 @pytest.mark.parametrize("feature", features.codecs)
-def test_check_codecs(feature) -> None:
+def test_check_codecs(feature: str) -> None:
     assert features.check_codec(feature) in [True, False]
 
 
@@ -116,9 +117,10 @@ def test_unsupported_module() -> None:
         features.version_module(module)
 
 
-def test_pilinfo() -> None:
+@pytest.mark.parametrize("supported_formats", (True, False))
+def test_pilinfo(supported_formats) -> None:
     buf = io.StringIO()
-    features.pilinfo(buf)
+    features.pilinfo(buf, supported_formats=supported_formats)
     out = buf.getvalue()
     lines = out.splitlines()
     assert lines[0] == "-" * 68
@@ -128,9 +130,15 @@ def test_pilinfo() -> None:
     while lines[0].startswith("    "):
         lines = lines[1:]
     assert lines[0] == "-" * 68
-    assert lines[1].startswith("Python modules loaded from ")
-    assert lines[2].startswith("Binary modules loaded from ")
-    assert lines[3] == "-" * 68
+    assert lines[1].startswith("Python executable is")
+    lines = lines[2:]
+    if lines[0].startswith("Environment Python files loaded from"):
+        lines = lines[1:]
+    assert lines[0].startswith("System Python files loaded from")
+    assert lines[1] == "-" * 68
+    assert lines[2].startswith("Python Pillow modules loaded from ")
+    assert lines[3].startswith("Binary Pillow modules loaded from ")
+    assert lines[4] == "-" * 68
     jpeg = (
         "\n"
         + "-" * 68
@@ -141,4 +149,4 @@ def test_pilinfo() -> None:
         + "-" * 68
         + "\n"
     )
-    assert jpeg in out
+    assert supported_formats == (jpeg in out)

Tests/test_file_apng.py

@@ -47,7 +47,7 @@ def test_apng_basic() -> None:
     "filename",
     ("Tests/images/apng/split_fdat.png", "Tests/images/apng/split_fdat_zero_chunk.png"),
 )
-def test_apng_fdat(filename) -> None:
+def test_apng_fdat(filename: str) -> None:
     with Image.open(filename) as im:
         im.seek(im.n_frames - 1)
         assert im.getpixel((0, 0)) == (0, 255, 0, 255)
@@ -338,7 +338,7 @@ def test_apng_syntax_errors() -> None:
         "sequence_fdat_fctl.png",
     ),
 )
-def test_apng_sequence_errors(test_file) -> None:
+def test_apng_sequence_errors(test_file: str) -> None:
     with pytest.raises(SyntaxError):
         with Image.open(f"Tests/images/apng/{test_file}") as im:
             im.seek(im.n_frames - 1)
@@ -668,6 +668,16 @@ def test_apng_save_blend(tmp_path: Path) -> None:
         assert im.getpixel((0, 0)) == (0, 255, 0, 255)
 
 
+def test_apng_save_size(tmp_path: Path) -> None:
+    test_file = str(tmp_path / "temp.png")
+
+    im = Image.new("L", (100, 100))
+    im.save(test_file, save_all=True, append_images=[Image.new("L", (200, 200))])
+
+    with Image.open(test_file) as reloaded:
+        assert reloaded.size == (200, 200)
+
+
 def test_seek_after_close() -> None:
     im = Image.open("Tests/images/apng/delay.png")
     im.seek(1)
@@ -681,7 +691,7 @@ def test_seek_after_close() -> None:
 @pytest.mark.parametrize("default_image", (True, False))
 @pytest.mark.parametrize("duplicate", (True, False))
 def test_different_modes_in_later_frames(
-    mode, default_image, duplicate, tmp_path: Path
+    mode: str, default_image: bool, duplicate: bool, tmp_path: Path
 ) -> None:
     test_file = str(tmp_path / "temp.png")
 

Tests/test_file_blp.py

@@ -71,7 +71,7 @@ def test_save(tmp_path: Path) -> None:
         "Tests/images/timeout-ef9112a065e7183fa7faa2e18929b03e44ee16bf.blp",
     ],
 )
-def test_crashes(test_file) -> None:
+def test_crashes(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with Image.open(f) as im:
             with pytest.raises(OSError):

Tests/test_file_bmp.py

@@ -16,7 +16,7 @@ from .helper import (
 
 
 def test_sanity(tmp_path: Path) -> None:
-    def roundtrip(im) -> None:
+    def roundtrip(im: Image.Image) -> None:
         outfile = str(tmp_path / "temp.bmp")
 
         im.save(outfile, "BMP")
@@ -194,7 +194,7 @@ def test_rle4() -> None:
         ("Tests/images/bmp/g/pal8rle.bmp", 1064),
     ),
 )
-def test_rle8_eof(file_name, length) -> None:
+def test_rle8_eof(file_name: str, length: int) -> None:
     with open(file_name, "rb") as fp:
         data = fp.read(length)
         with Image.open(io.BytesIO(data)) as im:

Tests/test_file_container.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+from typing import Literal
+
 import pytest
 
 from PIL import ContainerIO, Image
@@ -21,9 +23,16 @@ def test_isatty() -> None:
     assert container.isatty() is False
 
 
-def test_seek_mode_0() -> None:
+@pytest.mark.parametrize(
+    "mode, expected_position",
+    (
+        (0, 33),
+        (1, 66),
+        (2, 100),
+    ),
+)
+def test_seek_mode(mode: Literal[0, 1, 2], expected_position: int) -> None:
     # Arrange
-    mode = 0
     with open(TEST_FILE, "rb") as fh:
         container = ContainerIO.ContainerIO(fh, 22, 100)
 
@@ -32,39 +41,11 @@ def test_seek_mode_0() -> None:
         container.seek(33, mode)
 
         # Assert
-        assert container.tell() == 33
-
-
-def test_seek_mode_1() -> None:
-    # Arrange
-    mode = 1
-    with open(TEST_FILE, "rb") as fh:
-        container = ContainerIO.ContainerIO(fh, 22, 100)
-
-        # Act
-        container.seek(33, mode)
-        container.seek(33, mode)
-
-        # Assert
-        assert container.tell() == 66
-
-
-def test_seek_mode_2() -> None:
-    # Arrange
-    mode = 2
-    with open(TEST_FILE, "rb") as fh:
-        container = ContainerIO.ContainerIO(fh, 22, 100)
-
-        # Act
-        container.seek(33, mode)
-        container.seek(33, mode)
-
-        # Assert
-        assert container.tell() == 100
+        assert container.tell() == expected_position
 
 
 @pytest.mark.parametrize("bytesmode", (True, False))
-def test_read_n0(bytesmode) -> None:
+def test_read_n0(bytesmode: bool) -> None:
     # Arrange
     with open(TEST_FILE, "rb" if bytesmode else "r") as fh:
         container = ContainerIO.ContainerIO(fh, 22, 100)
@@ -80,7 +61,7 @@ def test_read_n0(bytesmode) -> None:
 
 
 @pytest.mark.parametrize("bytesmode", (True, False))
-def test_read_n(bytesmode) -> None:
+def test_read_n(bytesmode: bool) -> None:
     # Arrange
     with open(TEST_FILE, "rb" if bytesmode else "r") as fh:
         container = ContainerIO.ContainerIO(fh, 22, 100)
@@ -96,7 +77,7 @@ def test_read_n(bytesmode) -> None:
 
 
 @pytest.mark.parametrize("bytesmode", (True, False))
-def test_read_eof(bytesmode) -> None:
+def test_read_eof(bytesmode: bool) -> None:
     # Arrange
     with open(TEST_FILE, "rb" if bytesmode else "r") as fh:
         container = ContainerIO.ContainerIO(fh, 22, 100)
@@ -112,7 +93,7 @@ def test_read_eof(bytesmode) -> None:
 
 
 @pytest.mark.parametrize("bytesmode", (True, False))
-def test_readline(bytesmode) -> None:
+def test_readline(bytesmode: bool) -> None:
     # Arrange
     with open(TEST_FILE, "rb" if bytesmode else "r") as fh:
         container = ContainerIO.ContainerIO(fh, 0, 120)
@@ -127,7 +108,7 @@ def test_readline(bytesmode) -> None:
 
 
 @pytest.mark.parametrize("bytesmode", (True, False))
-def test_readlines(bytesmode) -> None:
+def test_readlines(bytesmode: bool) -> None:
     # Arrange
     expected = [
         "This is line 1\n",

Tests/test_file_dds.py

@@ -1,4 +1,5 @@
 """Test DdsImagePlugin"""
+
 from __future__ import annotations
 
 from io import BytesIO
@@ -47,7 +48,7 @@ TEST_FILE_UNCOMPRESSED_RGB_WITH_ALPHA = "Tests/images/uncompressed_rgb.dds"
         TEST_FILE_DX10_BC1_TYPELESS,
     ),
 )
-def test_sanity_dxt1_bc1(image_path) -> None:
+def test_sanity_dxt1_bc1(image_path: str) -> None:
     """Check DXT1 and BC1 images can be opened"""
     with Image.open(TEST_FILE_DXT1.replace(".dds", ".png")) as target:
         target = target.convert("RGBA")
@@ -95,7 +96,7 @@ def test_sanity_dxt5() -> None:
         TEST_FILE_BC4U,
     ),
 )
-def test_sanity_ati1_bc4u(image_path) -> None:
+def test_sanity_ati1_bc4u(image_path: str) -> None:
     """Check ATI1 and BC4U images can be opened"""
 
     with Image.open(image_path) as im:
@@ -116,7 +117,7 @@ def test_sanity_ati1_bc4u(image_path) -> None:
         TEST_FILE_DX10_BC4_TYPELESS,
     ),
 )
-def test_dx10_bc4(image_path) -> None:
+def test_dx10_bc4(image_path: str) -> None:
     """Check DX10 BC4 images can be opened"""
 
     with Image.open(image_path) as im:
@@ -137,7 +138,7 @@ def test_dx10_bc4(image_path) -> None:
         TEST_FILE_BC5U,
     ),
 )
-def test_sanity_ati2_bc5u(image_path) -> None:
+def test_sanity_ati2_bc5u(image_path: str) -> None:
     """Check ATI2 and BC5U images can be opened"""
 
     with Image.open(image_path) as im:
@@ -161,7 +162,7 @@ def test_sanity_ati2_bc5u(image_path) -> None:
         (TEST_FILE_BC5S, TEST_FILE_BC5S),
     ),
 )
-def test_dx10_bc5(image_path, expected_path) -> None:
+def test_dx10_bc5(image_path: str, expected_path: str) -> None:
     """Check DX10 BC5 images can be opened"""
 
     with Image.open(image_path) as im:
@@ -175,7 +176,7 @@ def test_dx10_bc5(image_path, expected_path) -> None:
 
 
 @pytest.mark.parametrize("image_path", (TEST_FILE_BC6H, TEST_FILE_BC6HS))
-def test_dx10_bc6h(image_path) -> None:
+def test_dx10_bc6h(image_path: str) -> None:
     """Check DX10 BC6H/BC6HS images can be opened"""
 
     with Image.open(image_path) as im:
@@ -256,7 +257,7 @@ def test_dx10_r8g8b8a8_unorm_srgb() -> None:
         ("RGBA", (800, 600), TEST_FILE_UNCOMPRESSED_RGB_WITH_ALPHA),
     ],
 )
-def test_uncompressed(mode, size, test_file) -> None:
+def test_uncompressed(mode: str, size: tuple[int, int], test_file: str) -> None:
     """Check uncompressed images can be opened"""
 
     with Image.open(test_file) as im:
@@ -358,7 +359,7 @@ def test_unsupported_bitcount() -> None:
         "Tests/images/unimplemented_pfflags.dds",
     ),
 )
-def test_not_implemented(test_file) -> None:
+def test_not_implemented(test_file: str) -> None:
     with pytest.raises(NotImplementedError):
         with Image.open(test_file):
             pass
@@ -380,7 +381,7 @@ def test_save_unsupported_mode(tmp_path: Path) -> None:
         ("RGBA", "Tests/images/pil123rgba.png"),
     ],
 )
-def test_save(mode, test_file, tmp_path: Path) -> None:
+def test_save(mode: str, test_file: str, tmp_path: Path) -> None:
     out = str(tmp_path / "temp.dds")
     with Image.open(test_file) as im:
         assert im.mode == mode

Tests/test_file_eps.py

@@ -5,7 +5,7 @@ from pathlib import Path
 
 import pytest
 
-from PIL import EpsImagePlugin, Image, features
+from PIL import EpsImagePlugin, Image, UnidentifiedImageError, features
 
 from .helper import (
     assert_image_similar,
@@ -84,7 +84,7 @@ simple_eps_file_with_long_binary_data = (
     ("filename", "size"), ((FILE1, (460, 352)), (FILE2, (360, 252)))
 )
 @pytest.mark.parametrize("scale", (1, 2))
-def test_sanity(filename, size, scale) -> None:
+def test_sanity(filename: str, size: tuple[int, int], scale: int) -> None:
     expected_size = tuple(s * scale for s in size)
     with Image.open(filename) as image:
         image.load(scale=scale)
@@ -129,28 +129,28 @@ def test_binary_header_only() -> None:
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_missing_version_comment(prefix) -> None:
+def test_missing_version_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_without_version))
     with pytest.raises(SyntaxError):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_missing_boundingbox_comment(prefix) -> None:
+def test_missing_boundingbox_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_without_boundingbox))
     with pytest.raises(SyntaxError, match='EPS header missing "%%BoundingBox" comment'):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_invalid_boundingbox_comment(prefix) -> None:
+def test_invalid_boundingbox_comment(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_invalid_boundingbox))
     with pytest.raises(OSError, match="cannot determine EPS bounding box"):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix) -> None:
+def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix: bytes) -> None:
     data = io.BytesIO(
         prefix + b"\n".join(simple_eps_file_with_invalid_boundingbox_valid_imagedata)
     )
@@ -161,21 +161,21 @@ def test_invalid_boundingbox_comment_valid_imagedata_comment(prefix) -> None:
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_ascii_comment_too_long(prefix) -> None:
+def test_ascii_comment_too_long(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_ascii_comment))
     with pytest.raises(SyntaxError, match="not an EPS file"):
         EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_long_binary_data(prefix) -> None:
+def test_long_binary_data(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_binary_data))
     EpsImagePlugin.EpsImageFile(data)
 
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("prefix", (b"", simple_binary_header))
-def test_load_long_binary_data(prefix) -> None:
+def test_load_long_binary_data(prefix: bytes) -> None:
     data = io.BytesIO(prefix + b"\n".join(simple_eps_file_with_long_binary_data))
     with Image.open(data) as img:
         img.load()
@@ -305,7 +305,7 @@ def test_render_scale2() -> None:
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("filename", (FILE1, FILE2, "Tests/images/illu10_preview.eps"))
-def test_resize(filename) -> None:
+def test_resize(filename: str) -> None:
     with Image.open(filename) as im:
         new_size = (100, 100)
         im = im.resize(new_size)
@@ -314,7 +314,7 @@ def test_resize(filename) -> None:
 
 @pytest.mark.skipif(not HAS_GHOSTSCRIPT, reason="Ghostscript not available")
 @pytest.mark.parametrize("filename", (FILE1, FILE2))
-def test_thumbnail(filename) -> None:
+def test_thumbnail(filename: str) -> None:
     # Issue #619
     with Image.open(filename) as im:
         new_size = (100, 100)
@@ -335,7 +335,7 @@ def test_readline_psfile(tmp_path: Path) -> None:
     line_endings = ["\r\n", "\n", "\n\r", "\r"]
     strings = ["something", "else", "baz", "bif"]
 
-    def _test_readline(t, ending) -> None:
+    def _test_readline(t: EpsImagePlugin.PSFile, ending: str) -> None:
         ending = "Failure with line ending: %s" % (
             "".join("%s" % ord(s) for s in ending)
         )
@@ -344,13 +344,13 @@ def test_readline_psfile(tmp_path: Path) -> None:
         assert t.readline().strip("\r\n") == "baz", ending
         assert t.readline().strip("\r\n") == "bif", ending
 
-    def _test_readline_io_psfile(test_string, ending) -> None:
+    def _test_readline_io_psfile(test_string: str, ending: str) -> None:
         f = io.BytesIO(test_string.encode("latin-1"))
         with pytest.warns(DeprecationWarning):
             t = EpsImagePlugin.PSFile(f)
         _test_readline(t, ending)
 
-    def _test_readline_file_psfile(test_string, ending) -> None:
+    def _test_readline_file_psfile(test_string: str, ending: str) -> None:
         f = str(tmp_path / "temp.txt")
         with open(f, "wb") as w:
             w.write(test_string.encode("latin-1"))
@@ -376,7 +376,7 @@ def test_psfile_deprecation() -> None:
     "line_ending",
     (b"\r\n", b"\n", b"\n\r", b"\r"),
 )
-def test_readline(prefix, line_ending) -> None:
+def test_readline(prefix: bytes, line_ending: bytes) -> None:
     simple_file = prefix + line_ending.join(simple_eps_file_with_comments)
     data = io.BytesIO(simple_file)
     test_file = EpsImagePlugin.EpsImageFile(data)
@@ -394,7 +394,7 @@ def test_readline(prefix, line_ending) -> None:
         "Tests/images/illuCS6_preview.eps",
     ),
 )
-def test_open_eps(filename) -> None:
+def test_open_eps(filename: str) -> None:
     # https://github.com/python-pillow/Pillow/issues/1104
     with Image.open(filename) as img:
         assert img.mode == "RGB"
@@ -417,9 +417,9 @@ def test_emptyline() -> None:
     "test_file",
     ["Tests/images/timeout-d675703545fee17acab56e5fec644c19979175de.eps"],
 )
-def test_timeout(test_file) -> None:
+def test_timeout(test_file: str) -> None:
     with open(test_file, "rb") as f:
-        with pytest.raises(Image.UnidentifiedImageError):
+        with pytest.raises(UnidentifiedImageError):
             with Image.open(f):
                 pass
 
@@ -437,3 +437,11 @@ def test_eof_before_bounding_box() -> None:
     with pytest.raises(OSError):
         with Image.open("Tests/images/zero_bb_eof_before_boundingbox.eps"):
             pass
+
+
+def test_invalid_data_after_eof() -> None:
+    with open("Tests/images/illuCS6_preview.eps", "rb") as f:
+        img_bytes = io.BytesIO(f.read() + b"\r\n%" + (b" " * 255))
+
+    with Image.open(img_bytes) as img:
+        assert img.mode == "RGB"

Tests/test_file_fits.py

@@ -6,7 +6,7 @@ import pytest
 
 from PIL import FitsImagePlugin, Image
 
-from .helper import assert_image_equal, hopper
+from .helper import assert_image_equal, assert_image_equal_tofile, hopper
 
 TEST_FILE = "Tests/images/hopper.fits"
 
@@ -22,6 +22,11 @@ def test_open() -> None:
         assert_image_equal(im, hopper("L"))
 
 
+def test_gzip1() -> None:
+    with Image.open("Tests/images/m13_gzip.fits") as im:
+        assert_image_equal_tofile(im, "Tests/images/m13.fits")
+
+
 def test_invalid_file() -> None:
     # Arrange
     invalid_file = "Tests/images/flower.jpg"

Tests/test_file_fli.py

@@ -4,7 +4,7 @@ import warnings
 
 import pytest
 
-from PIL import FliImagePlugin, Image
+from PIL import FliImagePlugin, Image, ImageFile
 
 from .helper import assert_image_equal, assert_image_equal_tofile, is_pypy
 
@@ -12,9 +12,12 @@ from .helper import assert_image_equal, assert_image_equal_tofile, is_pypy
 # save as...-> hopper.fli, default options.
 static_test_file = "Tests/images/hopper.fli"
 
-# From https://samples.libav.org/fli-flc/
+# From https://samples.ffmpeg.org/fli-flc/
 animated_test_file = "Tests/images/a.fli"
 
+# From https://samples.ffmpeg.org/fli-flc/
+animated_test_file_with_prefix_chunk = "Tests/images/2422.flc"
+
 
 def test_sanity() -> None:
     with Image.open(static_test_file) as im:
@@ -32,6 +35,24 @@ def test_sanity() -> None:
         assert im.is_animated
 
 
+def test_prefix_chunk() -> None:
+    ImageFile.LOAD_TRUNCATED_IMAGES = True
+    try:
+        with Image.open(animated_test_file_with_prefix_chunk) as im:
+            assert im.mode == "P"
+            assert im.size == (320, 200)
+            assert im.format == "FLI"
+            assert im.info["duration"] == 171
+            assert im.is_animated
+
+            palette = im.getpalette()
+            assert palette[3:6] == [255, 255, 255]
+            assert palette[381:384] == [204, 204, 12]
+            assert palette[765:] == [252, 0, 0]
+    finally:
+        ImageFile.LOAD_TRUNCATED_IMAGES = False
+
+
 @pytest.mark.skipif(is_pypy(), reason="Requires CPython")
 def test_unclosed_file() -> None:
     def open() -> None:
@@ -147,7 +168,7 @@ def test_seek() -> None:
     ],
 )
 @pytest.mark.timeout(timeout=3)
-def test_timeouts(test_file) -> None:
+def test_timeouts(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with Image.open(f) as im:
             with pytest.raises(OSError):
@@ -160,7 +181,7 @@ def test_timeouts(test_file) -> None:
         "Tests/images/crash-5762152299364352.fli",
     ],
 )
-def test_crash(test_file) -> None:
+def test_crash(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with Image.open(f) as im:
             with pytest.raises(OSError):

Tests/test_file_gif.py

@@ -3,6 +3,7 @@ from __future__ import annotations
 import warnings
 from io import BytesIO
 from pathlib import Path
+from typing import Generator
 
 import pytest
 
@@ -144,13 +145,13 @@ def test_strategy() -> None:
 
 
 def test_optimize() -> None:
-    def test_grayscale(optimize):
+    def test_grayscale(optimize: int) -> int:
         im = Image.new("L", (1, 1), 0)
         filename = BytesIO()
         im.save(filename, "GIF", optimize=optimize)
         return len(filename.getvalue())
 
-    def test_bilevel(optimize):
+    def test_bilevel(optimize: int) -> int:
         im = Image.new("1", (1, 1), 0)
         test_file = BytesIO()
         im.save(test_file, "GIF", optimize=optimize)
@@ -178,7 +179,9 @@ def test_optimize() -> None:
         (4, 513, 256),
     ),
 )
-def test_optimize_correctness(colors, size, expected_palette_length) -> None:
+def test_optimize_correctness(
+    colors: int, size: int, expected_palette_length: int
+) -> None:
     # 256 color Palette image, posterize to > 128 and < 128 levels.
     # Size bigger and smaller than 512x512.
     # Check the palette for number of colors allocated.
@@ -297,7 +300,7 @@ def test_roundtrip_save_all_1(tmp_path: Path) -> None:
         ("Tests/images/dispose_bgnd_rgba.gif", "RGBA"),
     ),
 )
-def test_loading_multiple_palettes(path, mode) -> None:
+def test_loading_multiple_palettes(path: str, mode: str) -> None:
     with Image.open(path) as im:
         assert im.mode == "P"
         first_frame_colors = im.palette.colors.keys()
@@ -347,9 +350,9 @@ def test_palette_handling(tmp_path: Path) -> None:
 def test_palette_434(tmp_path: Path) -> None:
     # see https://github.com/python-pillow/Pillow/issues/434
 
-    def roundtrip(im, *args, **kwargs):
+    def roundtrip(im: Image.Image, **kwargs: bool) -> Image.Image:
         out = str(tmp_path / "temp.gif")
-        im.copy().save(out, *args, **kwargs)
+        im.copy().save(out, **kwargs)
         reloaded = Image.open(out)
 
         return reloaded
@@ -429,7 +432,7 @@ def test_seek_rewind() -> None:
         ("Tests/images/iss634.gif", 42),
     ),
 )
-def test_n_frames(path, n_frames) -> None:
+def test_n_frames(path: str, n_frames: int) -> None:
     # Test is_animated before n_frames
     with Image.open(path) as im:
         assert im.is_animated == (n_frames != 1)
@@ -541,7 +544,10 @@ def test_dispose_background_transparency() -> None:
         ),
     ),
 )
-def test_transparent_dispose(loading_strategy, expected_colors) -> None:
+def test_transparent_dispose(
+    loading_strategy: GifImagePlugin.LoadingStrategy,
+    expected_colors: tuple[tuple[int | tuple[int, int, int, int], ...]],
+) -> None:
     GifImagePlugin.LOADING_STRATEGY = loading_strategy
     try:
         with Image.open("Tests/images/transparent_dispose.gif") as img:
@@ -641,6 +647,9 @@ def test_dispose2_palette(tmp_path: Path) -> None:
             # Center remains red every frame
             assert rgb_img.getpixel((50, 50)) == circle
 
+            # Check that frame transparency wasn't added unnecessarily
+            assert img._frame_transparency is None
+
 
 def test_dispose2_diff(tmp_path: Path) -> None:
     out = str(tmp_path / "temp.gif")
@@ -728,6 +737,25 @@ def test_dispose2_background_frame(tmp_path: Path) -> None:
         assert im.n_frames == 3
 
 
+def test_dispose2_previous_frame(tmp_path: Path) -> None:
+    out = str(tmp_path / "temp.gif")
+
+    im = Image.new("P", (100, 100))
+    im.info["transparency"] = 0
+    d = ImageDraw.Draw(im)
+    d.rectangle([(0, 0), (100, 50)], 1)
+    im.putpalette((0, 0, 0, 255, 0, 0))
+
+    im2 = Image.new("P", (100, 100))
+    im2.putpalette((0, 0, 0))
+
+    im.save(out, save_all=True, append_images=[im2], disposal=[0, 2])
+
+    with Image.open(out) as im:
+        im.seek(1)
+        assert im.getpixel((0, 0)) == (0, 0, 0, 255)
+
+
 def test_transparency_in_second_frame(tmp_path: Path) -> None:
     out = str(tmp_path / "temp.gif")
     with Image.open("Tests/images/different_transparency.gif") as im:
@@ -889,7 +917,9 @@ def test_identical_frames(tmp_path: Path) -> None:
         1500,
     ),
 )
-def test_identical_frames_to_single_frame(duration, tmp_path: Path) -> None:
+def test_identical_frames_to_single_frame(
+    duration: int | list[int], tmp_path: Path
+) -> None:
     out = str(tmp_path / "temp.gif")
     im_list = [
         Image.new("L", (100, 100), "#000"),
@@ -1049,7 +1079,7 @@ def test_retain_comment_in_subsequent_frames(tmp_path: Path) -> None:
 def test_version(tmp_path: Path) -> None:
     out = str(tmp_path / "temp.gif")
 
-    def assert_version_after_save(im, version) -> None:
+    def assert_version_after_save(im: Image.Image, version: bytes) -> None:
         im.save(out)
         with Image.open(out) as reread:
             assert reread.info["version"] == version
@@ -1088,7 +1118,7 @@ def test_append_images(tmp_path: Path) -> None:
         assert reread.n_frames == 3
 
     # Tests appending using a generator
-    def im_generator(ims):
+    def im_generator(ims: list[Image.Image]) -> Generator[Image.Image, None, None]:
         yield from ims
 
     im.save(out, save_all=True, append_images=im_generator(ims))
@@ -1105,6 +1135,21 @@ def test_append_images(tmp_path: Path) -> None:
         assert reread.n_frames == 10
 
 
+def test_append_different_size_image(tmp_path: Path) -> None:
+    out = str(tmp_path / "temp.gif")
+
+    im = Image.new("RGB", (100, 100))
+    bigger_im = Image.new("RGB", (200, 200), "#f00")
+
+    im.save(out, save_all=True, append_images=[bigger_im])
+
+    with Image.open(out) as reread:
+        assert reread.size == (100, 100)
+
+        reread.seek(1)
+        assert reread.size == (100, 100)
+
+
 def test_transparent_optimize(tmp_path: Path) -> None:
     # From issue #2195, if the transparent color is incorrectly optimized out, GIF loses
     # transparency.

Tests/test_file_gribstub.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from pathlib import Path
+from typing import IO
 
 import pytest
 
@@ -55,15 +56,15 @@ def test_handler(tmp_path: Path) -> None:
         loaded = False
         saved = False
 
-        def open(self, im) -> None:
+        def open(self, im: Image.Image) -> None:
             self.opened = True
 
-        def load(self, im):
+        def load(self, im: Image.Image) -> Image.Image:
             self.loaded = True
             im.fp.close()
             return Image.new("RGB", (1, 1))
 
-        def save(self, im, fp, filename) -> None:
+        def save(self, im: Image.Image, fp: IO[bytes], filename: str) -> None:
             self.saved = True
 
     handler = TestHandler()

Tests/test_file_hdf5stub.py

@@ -1,6 +1,7 @@
 from __future__ import annotations
 
 from pathlib import Path
+from typing import IO
 
 import pytest
 
@@ -56,15 +57,15 @@ def test_handler(tmp_path: Path) -> None:
         loaded = False
         saved = False
 
-        def open(self, im) -> None:
+        def open(self, im: Image.Image) -> None:
             self.opened = True
 
-        def load(self, im):
+        def load(self, im: Image.Image) -> Image.Image:
             self.loaded = True
             im.fp.close()
             return Image.new("RGB", (1, 1))
 
-        def save(self, im, fp, filename) -> None:
+        def save(self, im: Image.Image, fp: IO[bytes], filename: str) -> None:
             self.saved = True
 
     handler = TestHandler()

Tests/test_file_ico.py

@@ -38,6 +38,17 @@ def test_black_and_white() -> None:
         assert im.size == (16, 16)
 
 
+def test_palette(tmp_path: Path) -> None:
+    temp_file = str(tmp_path / "temp.ico")
+
+    im = Image.new("P", (16, 16))
+    im.save(temp_file)
+
+    with Image.open(temp_file) as reloaded:
+        assert reloaded.mode == "P"
+        assert reloaded.palette is not None
+
+
 def test_invalid_file() -> None:
     with open("Tests/images/flower.jpg", "rb") as fp:
         with pytest.raises(SyntaxError):
@@ -135,7 +146,7 @@ def test_different_bit_depths(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("mode", ("1", "L", "P", "RGB", "RGBA"))
-def test_save_to_bytes_bmp(mode) -> None:
+def test_save_to_bytes_bmp(mode: str) -> None:
     output = io.BytesIO()
     im = hopper(mode)
     im.save(output, "ico", bitmap_format="bmp", sizes=[(32, 32), (64, 64)])

Tests/test_file_im.py

@@ -82,7 +82,7 @@ def test_eoferror() -> None:
 
 
 @pytest.mark.parametrize("mode", ("RGB", "P", "PA"))
-def test_roundtrip(mode, tmp_path: Path) -> None:
+def test_roundtrip(mode: str, tmp_path: Path) -> None:
     out = str(tmp_path / "temp.im")
     im = hopper(mode)
     im.save(out)

Tests/test_file_iptc.py

@@ -98,7 +98,7 @@ def test_i() -> None:
     assert ret == 97
 
 
-def test_dump(monkeypatch) -> None:
+def test_dump(monkeypatch: pytest.MonkeyPatch) -> None:
     # Arrange
     c = b"abc"
     # Temporarily redirect stdout

Tests/test_file_jpeg.py

@@ -5,6 +5,8 @@ import re
 import warnings
 from io import BytesIO
 from pathlib import Path
+from types import ModuleType
+from typing import Any, cast
 
 import pytest
 
@@ -32,6 +34,7 @@ from .helper import (
     skip_unless_feature,
 )
 
+ElementTree: ModuleType | None
 try:
     from defusedxml import ElementTree
 except ImportError:
@@ -42,16 +45,22 @@ TEST_FILE = "Tests/images/hopper.jpg"
 
 @skip_unless_feature("jpg")
 class TestFileJpeg:
-    def roundtrip(self, im, **options):
+    def roundtrip_with_bytes(
+        self, im: Image.Image, **options: Any
+    ) -> tuple[JpegImagePlugin.JpegImageFile, int]:
         out = BytesIO()
         im.save(out, "JPEG", **options)
         test_bytes = out.tell()
         out.seek(0)
-        im = Image.open(out)
-        im.bytes = test_bytes  # for testing only
-        return im
+        reloaded = cast(JpegImagePlugin.JpegImageFile, Image.open(out))
+        return reloaded, test_bytes
 
-    def gen_random_image(self, size, mode: str = "RGB"):
+    def roundtrip(
+        self, im: Image.Image, **options: Any
+    ) -> JpegImagePlugin.JpegImageFile:
+        return self.roundtrip_with_bytes(im, **options)[0]
+
+    def gen_random_image(self, size: tuple[int, int], mode: str = "RGB") -> Image.Image:
         """Generates a very hard to compress file
         :param size: tuple
         :param mode: optional image mode
@@ -71,7 +80,7 @@ class TestFileJpeg:
             assert im.get_format_mimetype() == "image/jpeg"
 
     @pytest.mark.parametrize("size", ((1, 0), (0, 1), (0, 0)))
-    def test_zero(self, size, tmp_path: Path) -> None:
+    def test_zero(self, size: tuple[int, int], tmp_path: Path) -> None:
         f = str(tmp_path / "temp.jpg")
         im = Image.new("RGB", size)
         with pytest.raises(ValueError):
@@ -108,13 +117,11 @@ class TestFileJpeg:
                     assert "comment" not in reloaded.info
 
             # Test that a comment argument overrides the default comment
-            for comment in ("Test comment text", b"Text comment text"):
+            for comment in ("Test comment text", b"Test comment text"):
                 out = BytesIO()
                 im.save(out, format="JPEG", comment=comment)
                 with Image.open(out) as reloaded:
-                    if not isinstance(comment, bytes):
-                        comment = comment.encode()
-                    assert reloaded.info["comment"] == comment
+                    assert reloaded.info["comment"] == b"Test comment text"
 
     def test_cmyk(self) -> None:
         # Test CMYK handling.  Thanks to Tim and Charlie for test data,
@@ -145,7 +152,7 @@ class TestFileJpeg:
             assert k > 0.9
 
     def test_rgb(self) -> None:
-        def getchannels(im):
+        def getchannels(im: Image.Image) -> tuple[int, int, int]:
             return tuple(v[0] for v in im.layer)
 
         im = hopper()
@@ -161,8 +168,8 @@ class TestFileJpeg:
         "test_image_path",
         [TEST_FILE, "Tests/images/pil_sample_cmyk.jpg"],
     )
-    def test_dpi(self, test_image_path) -> None:
-        def test(xdpi, ydpi=None):
+    def test_dpi(self, test_image_path: str) -> None:
+        def test(xdpi: int, ydpi: int | None = None):
             with Image.open(test_image_path) as im:
                 im = self.roundtrip(im, dpi=(xdpi, ydpi or xdpi))
             return im.info.get("dpi")
@@ -207,7 +214,7 @@ class TestFileJpeg:
             ImageFile.MAXBLOCK * 4 + 3,  # large block
         ),
     )
-    def test_icc_big(self, n) -> None:
+    def test_icc_big(self, n: int) -> None:
         # Make sure that the "extra" support handles large blocks
         # The ICC APP marker can store 65519 bytes per marker, so
         # using a 4-byte test code should allow us to detect out of
@@ -245,13 +252,13 @@ class TestFileJpeg:
             im.save(f, progressive=True, quality=94, exif=b" " * 43668)
 
     def test_optimize(self) -> None:
-        im1 = self.roundtrip(hopper())
-        im2 = self.roundtrip(hopper(), optimize=0)
-        im3 = self.roundtrip(hopper(), optimize=1)
+        im1, im1_bytes = self.roundtrip_with_bytes(hopper())
+        im2, im2_bytes = self.roundtrip_with_bytes(hopper(), optimize=0)
+        im3, im3_bytes = self.roundtrip_with_bytes(hopper(), optimize=1)
         assert_image_equal(im1, im2)
         assert_image_equal(im1, im3)
-        assert im1.bytes >= im2.bytes
-        assert im1.bytes >= im3.bytes
+        assert im1_bytes >= im2_bytes
+        assert im1_bytes >= im3_bytes
 
     def test_optimize_large_buffer(self, tmp_path: Path) -> None:
         # https://github.com/python-pillow/Pillow/issues/148
@@ -261,15 +268,15 @@ class TestFileJpeg:
         im.save(f, format="JPEG", optimize=True)
 
     def test_progressive(self) -> None:
-        im1 = self.roundtrip(hopper())
+        im1, im1_bytes = self.roundtrip_with_bytes(hopper())
         im2 = self.roundtrip(hopper(), progressive=False)
-        im3 = self.roundtrip(hopper(), progressive=True)
+        im3, im3_bytes = self.roundtrip_with_bytes(hopper(), progressive=True)
         assert not im1.info.get("progressive")
         assert not im2.info.get("progressive")
         assert im3.info.get("progressive")
 
         assert_image_equal(im1, im3)
-        assert im1.bytes >= im3.bytes
+        assert im1_bytes >= im3_bytes
 
     def test_progressive_large_buffer(self, tmp_path: Path) -> None:
         f = str(tmp_path / "temp.jpg")
@@ -340,6 +347,7 @@ class TestFileJpeg:
             assert exif.get_ifd(0x8825) == {}
 
             transposed = ImageOps.exif_transpose(im)
+        assert transposed is not None
         exif = transposed.getexif()
         assert exif.get_ifd(0x8825) == {}
 
@@ -418,14 +426,14 @@ class TestFileJpeg:
         assert im3.info.get("progression")
 
     def test_quality(self) -> None:
-        im1 = self.roundtrip(hopper())
-        im2 = self.roundtrip(hopper(), quality=50)
+        im1, im1_bytes = self.roundtrip_with_bytes(hopper())
+        im2, im2_bytes = self.roundtrip_with_bytes(hopper(), quality=50)
         assert_image(im1, im2.mode, im2.size)
-        assert im1.bytes >= im2.bytes
+        assert im1_bytes >= im2_bytes
 
-        im3 = self.roundtrip(hopper(), quality=0)
+        im3, im3_bytes = self.roundtrip_with_bytes(hopper(), quality=0)
         assert_image(im1, im3.mode, im3.size)
-        assert im2.bytes > im3.bytes
+        assert im2_bytes > im3_bytes
 
     def test_smooth(self) -> None:
         im1 = self.roundtrip(hopper())
@@ -433,7 +441,7 @@ class TestFileJpeg:
         assert_image(im1, im2.mode, im2.size)
 
     def test_subsampling(self) -> None:
-        def getsampling(im):
+        def getsampling(im: Image.Image):
             layer = im.layer
             return layer[0][1:3] + layer[1][1:3] + layer[2][1:3]
 
@@ -441,25 +449,25 @@ class TestFileJpeg:
         for subsampling in (-1, 3):  # (default, invalid)
             im = self.roundtrip(hopper(), subsampling=subsampling)
             assert getsampling(im) == (2, 2, 1, 1, 1, 1)
-        for subsampling in (0, "4:4:4"):
-            im = self.roundtrip(hopper(), subsampling=subsampling)
+        for subsampling1 in (0, "4:4:4"):
+            im = self.roundtrip(hopper(), subsampling=subsampling1)
             assert getsampling(im) == (1, 1, 1, 1, 1, 1)
-        for subsampling in (1, "4:2:2"):
-            im = self.roundtrip(hopper(), subsampling=subsampling)
+        for subsampling1 in (1, "4:2:2"):
+            im = self.roundtrip(hopper(), subsampling=subsampling1)
             assert getsampling(im) == (2, 1, 1, 1, 1, 1)
-        for subsampling in (2, "4:2:0", "4:1:1"):
-            im = self.roundtrip(hopper(), subsampling=subsampling)
+        for subsampling1 in (2, "4:2:0", "4:1:1"):
+            im = self.roundtrip(hopper(), subsampling=subsampling1)
             assert getsampling(im) == (2, 2, 1, 1, 1, 1)
 
         # RGB colorspace
-        for subsampling in (-1, 0, "4:4:4"):
+        for subsampling1 in (-1, 0, "4:4:4"):
             # "4:4:4" doesn't really make sense for RGB, but the conversion
             # to an integer happens at a higher level
-            im = self.roundtrip(hopper(), keep_rgb=True, subsampling=subsampling)
+            im = self.roundtrip(hopper(), keep_rgb=True, subsampling=subsampling1)
             assert getsampling(im) == (1, 1, 1, 1, 1, 1)
-        for subsampling in (1, "4:2:2", 2, "4:2:0", 3):
+        for subsampling1 in (1, "4:2:2", 2, "4:2:0", 3):
             with pytest.raises(OSError):
-                self.roundtrip(hopper(), keep_rgb=True, subsampling=subsampling)
+                self.roundtrip(hopper(), keep_rgb=True, subsampling=subsampling1)
 
         with pytest.raises(TypeError):
             self.roundtrip(hopper(), subsampling="1:1:1")
@@ -530,7 +538,7 @@ class TestFileJpeg:
         pytest.mark.valgrind_known_error, "libjpeg_turbo", "2.0", reason="Known Failing"
     )
     def test_qtables(self, tmp_path: Path) -> None:
-        def _n_qtables_helper(n, test_file) -> None:
+        def _n_qtables_helper(n: int, test_file: str) -> None:
             with Image.open(test_file) as im:
                 f = str(tmp_path / "temp.jpg")
                 im.save(f, qtables=[[n] * 64] * n)
@@ -666,7 +674,7 @@ class TestFileJpeg:
         "blocks, rows, markers",
         ((0, 0, 0), (1, 0, 15), (3, 0, 5), (8, 0, 1), (0, 1, 3), (0, 2, 1)),
     )
-    def test_restart_markers(self, blocks, rows, markers) -> None:
+    def test_restart_markers(self, blocks: int, rows: int, markers: int) -> None:
         im = Image.new("RGB", (32, 32))  # 16 MCUs
         out = BytesIO()
         im.save(
@@ -724,13 +732,13 @@ class TestFileJpeg:
             assert im.format == "JPEG"
 
     @pytest.mark.parametrize("mode", ("1", "L", "RGB", "RGBX", "CMYK", "YCbCr"))
-    def test_save_correct_modes(self, mode) -> None:
+    def test_save_correct_modes(self, mode: str) -> None:
         out = BytesIO()
         img = Image.new(mode, (20, 20))
         img.save(out, "JPEG")
 
     @pytest.mark.parametrize("mode", ("LA", "La", "RGBA", "RGBa", "P"))
-    def test_save_wrong_modes(self, mode) -> None:
+    def test_save_wrong_modes(self, mode: str) -> None:
         # ref https://github.com/python-pillow/Pillow/issues/2005
         out = BytesIO()
         img = Image.new(mode, (20, 20))
@@ -817,7 +825,7 @@ class TestFileJpeg:
         with Image.open("Tests/images/no-dpi-in-exif.jpg") as im:
             # Act / Assert
             # "When the image resolution is unknown, 72 [dpi] is designated."
-            # https://exiv2.org/tags.html
+            # https://web.archive.org/web/20240227115053/https://exiv2.org/tags.html
             assert im.info.get("dpi") == (72, 72)
 
     def test_invalid_exif(self) -> None:
@@ -982,16 +990,10 @@ class TestFileJpeg:
         # Even though this decoder never says that it is finished
         # the image should still end when there is no new data
         class InfiniteMockPyDecoder(ImageFile.PyDecoder):
-            def decode(self, buffer):
+            def decode(self, buffer: bytes) -> tuple[int, int]:
                 return 0, 0
 
-        decoder = InfiniteMockPyDecoder(None)
-
-        def closure(mode, *args):
-            decoder.__init__(mode, *args)
-            return decoder
-
-        Image.register_decoder("INFINITE", closure)
+        Image.register_decoder("INFINITE", InfiniteMockPyDecoder)
 
         with Image.open(TEST_FILE) as im:
             im.tile = [

Tests/test_file_jpeg2k.py

@@ -4,6 +4,7 @@ import os
 import re
 from io import BytesIO
 from pathlib import Path
+from typing import Any
 
 import pytest
 
@@ -36,13 +37,11 @@ test_card.load()
 # 'Not enough memory to handle tile data'
 
 
-def roundtrip(im, **options):
+def roundtrip(im: Image.Image, **options: Any) -> Image.Image:
     out = BytesIO()
     im.save(out, "JPEG2000", **options)
-    test_bytes = out.tell()
     out.seek(0)
     with Image.open(out) as im:
-        im.bytes = test_bytes  # for testing only
         im.load()
     return im
 
@@ -76,7 +75,9 @@ def test_invalid_file() -> None:
 def test_bytesio() -> None:
     with open("Tests/images/test-card-lossless.jp2", "rb") as f:
         data = BytesIO(f.read())
-    assert_image_similar_tofile(test_card, data, 1.0e-3)
+    with Image.open(data) as im:
+        im.load()
+        assert_image_similar(im, test_card, 1.0e-3)
 
 
 # These two test pre-written JPEG 2000 files that were not written with
@@ -138,7 +139,7 @@ def test_prog_res_rt() -> None:
 
 
 @pytest.mark.parametrize("num_resolutions", range(2, 6))
-def test_default_num_resolutions(num_resolutions) -> None:
+def test_default_num_resolutions(num_resolutions: int) -> None:
     d = 1 << (num_resolutions - 1)
     im = test_card.resize((d - 1, d - 1))
     with pytest.raises(OSError):
@@ -198,9 +199,9 @@ def test_layers_type(tmp_path: Path) -> None:
     for quality_layers in [[100, 50, 10], (100, 50, 10), None]:
         test_card.save(outfile, quality_layers=quality_layers)
 
-    for quality_layers in ["quality_layers", ("100", "50", "10")]:
+    for quality_layers_str in ["quality_layers", ("100", "50", "10")]:
         with pytest.raises(ValueError):
-            test_card.save(outfile, quality_layers=quality_layers)
+            test_card.save(outfile, quality_layers=quality_layers_str)
 
 
 def test_layers() -> None:
@@ -233,7 +234,7 @@ def test_layers() -> None:
         ("foo.jp2", {"no_jp2": False}, 4, b"jP"),
     ),
 )
-def test_no_jp2(name, args, offset, data) -> None:
+def test_no_jp2(name: str, args: dict[str, bool], offset: int, data: bytes) -> None:
     out = BytesIO()
     if name:
         out.name = name
@@ -278,7 +279,7 @@ def test_sgnd(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("ext", (".j2k", ".jp2"))
-def test_rgba(ext) -> None:
+def test_rgba(ext: str) -> None:
     # Arrange
     with Image.open("Tests/images/rgb_trns_ycbc" + ext) as im:
         # Act
@@ -289,7 +290,7 @@ def test_rgba(ext) -> None:
 
 
 @pytest.mark.parametrize("ext", (".j2k", ".jp2"))
-def test_16bit_monochrome_has_correct_mode(ext) -> None:
+def test_16bit_monochrome_has_correct_mode(ext: str) -> None:
     with Image.open("Tests/images/16bit.cropped" + ext) as im:
         im.load()
         assert im.mode == "I;16"
@@ -339,6 +340,7 @@ def test_parser_feed() -> None:
     p.feed(data)
 
     # Assert
+    assert p.image is not None
     assert p.image.size == (640, 480)
 
 
@@ -346,12 +348,12 @@ def test_parser_feed() -> None:
     not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
 )
 @pytest.mark.parametrize("name", ("subsampling_1", "subsampling_2", "zoo1", "zoo2"))
-def test_subsampling_decode(name) -> None:
+def test_subsampling_decode(name: str) -> None:
     test = f"{EXTRA_DIR}/{name}.jp2"
     reference = f"{EXTRA_DIR}/{name}.ppm"
 
     with Image.open(test) as im:
-        epsilon = 3  # for YCbCr images
+        epsilon = 3.0  # for YCbCr images
         with Image.open(reference) as im2:
             width, height = im2.size
             if name[-1] == "2":
@@ -362,6 +364,16 @@ def test_subsampling_decode(name) -> None:
         assert_image_similar(im, expected, epsilon)
 
 
+@pytest.mark.skipif(
+    not os.path.exists(EXTRA_DIR), reason="Extra image files not installed"
+)
+def test_pclr() -> None:
+    with Image.open(f"{EXTRA_DIR}/issue104_jpxstream.jp2") as im:
+        assert im.mode == "P"
+        assert len(im.palette.colors) == 256
+        assert im.palette.colors[(255, 255, 255)] == 0
+
+
 def test_comment() -> None:
     with Image.open("Tests/images/comment.jp2") as im:
         assert im.info["comment"] == b"Created by OpenJPEG version 2.5.0"
@@ -400,7 +412,7 @@ def test_save_comment() -> None:
         "Tests/images/crash-d2c93af851d3ab9a19e34503626368b2ecde9c03.j2k",
     ],
 )
-def test_crashes(test_file) -> None:
+def test_crashes(test_file: str) -> None:
     with open(test_file, "rb") as f:
         with Image.open(f) as im:
             # Valgrind should not complain here
@@ -434,3 +446,9 @@ def test_plt_marker() -> None:
         hdr = out.read(2)
         length = _binary.i16be(hdr)
         out.seek(length - 2, os.SEEK_CUR)
+
+
+def test_9bit():
+    with Image.open("Tests/images/9bit.j2k") as im:
+        assert im.mode == "I;16"
+        assert im.size == (128, 128)

Tests/test_file_libtiff.py

@@ -6,13 +6,13 @@ import itertools
 import os
 import re
 import sys
-from collections import namedtuple
 from pathlib import Path
+from typing import Any, NamedTuple
 
 import pytest
 
 from PIL import Image, ImageFilter, ImageOps, TiffImagePlugin, TiffTags, features
-from PIL.TiffImagePlugin import SAMPLEFORMAT, STRIPOFFSETS, SUBIFD
+from PIL.TiffImagePlugin import OSUBFILETYPE, SAMPLEFORMAT, STRIPOFFSETS, SUBIFD
 
 from .helper import (
     assert_image_equal,
@@ -27,7 +27,7 @@ from .helper import (
 
 @skip_unless_feature("libtiff")
 class LibTiffTestCase:
-    def _assert_noerr(self, tmp_path: Path, im) -> None:
+    def _assert_noerr(self, tmp_path: Path, im: TiffImagePlugin.TiffImageFile) -> None:
         """Helper tests that assert basic sanity about the g4 tiff reading"""
         # 1 bit
         assert im.mode == "1"
@@ -140,7 +140,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert_image_equal_tofile(im, "Tests/images/tiff_adobe_deflate.png")
 
     @pytest.mark.parametrize("legacy_api", (False, True))
-    def test_write_metadata(self, legacy_api, tmp_path: Path) -> None:
+    def test_write_metadata(self, legacy_api: bool, tmp_path: Path) -> None:
         """Test metadata writing through libtiff"""
         f = str(tmp_path / "temp.tiff")
         with Image.open("Tests/images/hopper_g4.tif") as img:
@@ -243,36 +243,40 @@ class TestFileLibTiff(LibTiffTestCase):
         TiffImagePlugin.WRITE_LIBTIFF = False
 
     def test_custom_metadata(self, tmp_path: Path) -> None:
-        tc = namedtuple("test_case", "value,type,supported_by_default")
+        class Tc(NamedTuple):
+            value: Any
+            type: int
+            supported_by_default: bool
+
         custom = {
             37000 + k: v
             for k, v in enumerate(
                 [
-                    tc(4, TiffTags.SHORT, True),
-                    tc(123456789, TiffTags.LONG, True),
-                    tc(-4, TiffTags.SIGNED_BYTE, False),
-                    tc(-4, TiffTags.SIGNED_SHORT, False),
-                    tc(-123456789, TiffTags.SIGNED_LONG, False),
-                    tc(TiffImagePlugin.IFDRational(4, 7), TiffTags.RATIONAL, True),
-                    tc(4.25, TiffTags.FLOAT, True),
-                    tc(4.25, TiffTags.DOUBLE, True),
-                    tc("custom tag value", TiffTags.ASCII, True),
-                    tc(b"custom tag value", TiffTags.BYTE, True),
-                    tc((4, 5, 6), TiffTags.SHORT, True),
-                    tc((123456789, 9, 34, 234, 219387, 92432323), TiffTags.LONG, True),
-                    tc((-4, 9, 10), TiffTags.SIGNED_BYTE, False),
-                    tc((-4, 5, 6), TiffTags.SIGNED_SHORT, False),
-                    tc(
+                    Tc(4, TiffTags.SHORT, True),
+                    Tc(123456789, TiffTags.LONG, True),
+                    Tc(-4, TiffTags.SIGNED_BYTE, False),
+                    Tc(-4, TiffTags.SIGNED_SHORT, False),
+                    Tc(-123456789, TiffTags.SIGNED_LONG, False),
+                    Tc(TiffImagePlugin.IFDRational(4, 7), TiffTags.RATIONAL, True),
+                    Tc(4.25, TiffTags.FLOAT, True),
+                    Tc(4.25, TiffTags.DOUBLE, True),
+                    Tc("custom tag value", TiffTags.ASCII, True),
+                    Tc(b"custom tag value", TiffTags.BYTE, True),
+                    Tc((4, 5, 6), TiffTags.SHORT, True),
+                    Tc((123456789, 9, 34, 234, 219387, 92432323), TiffTags.LONG, True),
+                    Tc((-4, 9, 10), TiffTags.SIGNED_BYTE, False),
+                    Tc((-4, 5, 6), TiffTags.SIGNED_SHORT, False),
+                    Tc(
                         (-123456789, 9, 34, 234, 219387, -92432323),
                         TiffTags.SIGNED_LONG,
                         False,
                     ),
-                    tc((4.25, 5.25), TiffTags.FLOAT, True),
-                    tc((4.25, 5.25), TiffTags.DOUBLE, True),
+                    Tc((4.25, 5.25), TiffTags.FLOAT, True),
+                    Tc((4.25, 5.25), TiffTags.DOUBLE, True),
                     # array of TIFF_BYTE requires bytes instead of tuple for backwards
                     # compatibility
-                    tc(bytes([4]), TiffTags.BYTE, True),
-                    tc(bytes((4, 9, 10)), TiffTags.BYTE, True),
+                    Tc(bytes([4]), TiffTags.BYTE, True),
+                    Tc(bytes((4, 9, 10)), TiffTags.BYTE, True),
                 ]
             )
         }
@@ -284,7 +288,9 @@ class TestFileLibTiff(LibTiffTestCase):
         for libtiff in libtiffs:
             TiffImagePlugin.WRITE_LIBTIFF = libtiff
 
-            def check_tags(tiffinfo) -> None:
+            def check_tags(
+                tiffinfo: TiffImagePlugin.ImageFileDirectory_v2 | dict[int, str]
+            ) -> None:
                 im = hopper()
 
                 out = str(tmp_path / "temp.tif")
@@ -323,6 +329,12 @@ class TestFileLibTiff(LibTiffTestCase):
             )
         TiffImagePlugin.WRITE_LIBTIFF = False
 
+    def test_osubfiletype(self, tmp_path: Path) -> None:
+        outfile = str(tmp_path / "temp.tif")
+        with Image.open("Tests/images/g4_orientation_6.tif") as im:
+            im.tag_v2[OSUBFILETYPE] = 1
+            im.save(outfile)
+
     def test_subifd(self, tmp_path: Path) -> None:
         outfile = str(tmp_path / "temp.tif")
         with Image.open("Tests/images/g4_orientation_6.tif") as im:
@@ -502,7 +514,7 @@ class TestFileLibTiff(LibTiffTestCase):
         assert_image_equal_tofile(im, out)
 
     @pytest.mark.parametrize("im", (hopper("P"), Image.new("P", (1, 1), "#000")))
-    def test_palette_save(self, im, tmp_path: Path) -> None:
+    def test_palette_save(self, im: Image.Image, tmp_path: Path) -> None:
         out = str(tmp_path / "temp.tif")
 
         TiffImagePlugin.WRITE_LIBTIFF = True
@@ -514,7 +526,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert len(reloaded.tag_v2[320]) == 768
 
     @pytest.mark.parametrize("compression", ("tiff_ccitt", "group3", "group4"))
-    def test_bw_compression_w_rgb(self, compression, tmp_path: Path) -> None:
+    def test_bw_compression_w_rgb(self, compression: str, tmp_path: Path) -> None:
         im = hopper("RGB")
         out = str(tmp_path / "temp.tif")
 
@@ -522,7 +534,8 @@ class TestFileLibTiff(LibTiffTestCase):
             im.save(out, compression=compression)
 
     def test_fp_leak(self) -> None:
-        im = Image.open("Tests/images/hopper_g4_500.tif")
+        im: Image.Image | None = Image.open("Tests/images/hopper_g4_500.tif")
+        assert im is not None
         fn = im.fp.fileno()
 
         os.fstat(fn)
@@ -647,7 +660,7 @@ class TestFileLibTiff(LibTiffTestCase):
         # Generate test image
         pilim = hopper()
 
-        def save_bytesio(compression=None) -> None:
+        def save_bytesio(compression: str | None = None) -> None:
             buffer_io = io.BytesIO()
             pilim.save(buffer_io, format="tiff", compression=compression)
             buffer_io.seek(0)
@@ -714,6 +727,7 @@ class TestFileLibTiff(LibTiffTestCase):
                 f.write(src.read())
 
         im = Image.open(tmpfile)
+        assert isinstance(im, TiffImagePlugin.TiffImageFile)
         im.n_frames
         im.close()
         # Should not raise PermissionError.
@@ -731,7 +745,7 @@ class TestFileLibTiff(LibTiffTestCase):
         assert icc == icc_libtiff
 
     def test_write_icc(self, tmp_path: Path) -> None:
-        def check_write(libtiff) -> None:
+        def check_write(libtiff: bool) -> None:
             TiffImagePlugin.WRITE_LIBTIFF = libtiff
 
             with Image.open("Tests/images/hopper.iccprofile.tif") as img:
@@ -837,7 +851,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert reloaded.mode == "F"
             assert reloaded.getexif()[SAMPLEFORMAT] == 3
 
-    def test_lzma(self, capfd):
+    def test_lzma(self, capfd: pytest.CaptureFixture[str]) -> None:
         try:
             with Image.open("Tests/images/hopper_lzma.tif") as im:
                 assert im.mode == "RGB"
@@ -853,7 +867,7 @@ class TestFileLibTiff(LibTiffTestCase):
             sys.stderr.write(captured.err)
             raise
 
-    def test_webp(self, capfd):
+    def test_webp(self, capfd: pytest.CaptureFixture[str]) -> None:
         try:
             with Image.open("Tests/images/hopper_webp.tif") as im:
                 assert im.mode == "RGB"
@@ -971,7 +985,7 @@ class TestFileLibTiff(LibTiffTestCase):
             assert_image_equal_tofile(im, "Tests/images/tiff_16bit_RGBa_target.png")
 
     @pytest.mark.parametrize("compression", (None, "jpeg"))
-    def test_block_tile_tags(self, compression, tmp_path: Path) -> None:
+    def test_block_tile_tags(self, compression: str | None, tmp_path: Path) -> None:
         im = hopper()
         out = str(tmp_path / "temp.tif")
 
@@ -1020,7 +1034,9 @@ class TestFileLibTiff(LibTiffTestCase):
             ),
         ],
     )
-    def test_wrong_bits_per_sample(self, file_name, mode, size, tile) -> None:
+    def test_wrong_bits_per_sample(
+        self, file_name: str, mode: str, size: tuple[int, int], tile
+    ) -> None:
         with Image.open("Tests/images/" + file_name) as im:
             assert im.mode == mode
             assert im.size == size
@@ -1086,35 +1102,37 @@ class TestFileLibTiff(LibTiffTestCase):
         TiffImagePlugin.READ_LIBTIFF = False
 
     @pytest.mark.parametrize("compression", ("tiff_adobe_deflate", "jpeg"))
-    def test_save_multistrip(self, compression, tmp_path: Path) -> None:
+    def test_save_multistrip(self, compression: str, tmp_path: Path) -> None:
         im = hopper("RGB").resize((256, 256))
         out = str(tmp_path / "temp.tif")
         im.save(out, compression=compression)
 
         with Image.open(out) as im:
             # Assert that there are multiple strips
+            assert isinstance(im, TiffImagePlugin.TiffImageFile)
             assert len(im.tag_v2[STRIPOFFSETS]) > 1
 
     @pytest.mark.parametrize("argument", (True, False))
-    def test_save_single_strip(self, argument, tmp_path: Path) -> None:
+    def test_save_single_strip(self, argument: bool, tmp_path: Path) -> None:
         im = hopper("RGB").resize((256, 256))
         out = str(tmp_path / "temp.tif")
 
         if not argument:
             TiffImagePlugin.STRIP_SIZE = 2**18
         try:
-            arguments = {"compression": "tiff_adobe_deflate"}
+            arguments: dict[str, str | int] = {"compression": "tiff_adobe_deflate"}
             if argument:
                 arguments["strip_size"] = 2**18
             im.save(out, **arguments)
 
             with Image.open(out) as im:
+                assert isinstance(im, TiffImagePlugin.TiffImageFile)
                 assert len(im.tag_v2[STRIPOFFSETS]) == 1
         finally:
             TiffImagePlugin.STRIP_SIZE = 65536
 
     @pytest.mark.parametrize("compression", ("tiff_adobe_deflate", None))
-    def test_save_zero(self, compression, tmp_path: Path) -> None:
+    def test_save_zero(self, compression: str | None, tmp_path: Path) -> None:
         im = Image.new("RGB", (0, 0))
         out = str(tmp_path / "temp.tif")
         with pytest.raises(SystemError):
@@ -1134,7 +1152,7 @@ class TestFileLibTiff(LibTiffTestCase):
             ("Tests/images/child_ifd_jpeg.tiff", (20,)),
         ),
     )
-    def test_get_child_images(self, path, sizes) -> None:
+    def test_get_child_images(self, path: str, sizes: tuple[int, ...]) -> None:
         with Image.open(path) as im:
             ims = im.get_child_images()
 

Tests/test_file_libtiff_small.py

@@ -9,7 +9,6 @@ from .test_file_libtiff import LibTiffTestCase
 
 
 class TestFileLibTiffSmall(LibTiffTestCase):
-
     """The small lena image was failing on open in the libtiff
     decoder because the file pointer was set to the wrong place
     by a spurious seek. It wasn't failing with the byteio method.

Tests/test_file_mcidas.py

@@ -19,7 +19,7 @@ def test_valid_file() -> None:
     # https://ghrc.nsstc.nasa.gov/hydro/details/cmx3g8
     # https://ghrc.nsstc.nasa.gov/pub/fieldCampaigns/camex3/cmx3g8/browse/
     test_file = "Tests/images/cmx3g8_wv_1998.260_0745_mcidas.ara"
-    saved_file = "Tests/images/cmx3g8_wv_1998.260_0745_mcidas.png"
+    saved_file = "Tests/images/cmx3g8_wv_1998.260_0745_mcidas.tiff"
 
     # Act
     with Image.open(test_file) as im:

Tests/test_file_mpo.py

@@ -2,10 +2,11 @@ from __future__ import annotations
 
 import warnings
 from io import BytesIO
+from typing import Any, cast
 
 import pytest
 
-from PIL import Image
+from PIL import Image, MpoImagePlugin
 
 from .helper import (
     assert_image_equal,
@@ -19,18 +20,15 @@ test_files = ["Tests/images/sugarshack.mpo", "Tests/images/frozenpond.mpo"]
 pytestmark = skip_unless_feature("jpg")
 
 
-def roundtrip(im, **options):
+def roundtrip(im: Image.Image, **options: Any) -> MpoImagePlugin.MpoImageFile:
     out = BytesIO()
     im.save(out, "MPO", **options)
-    test_bytes = out.tell()
     out.seek(0)
-    im = Image.open(out)
-    im.bytes = test_bytes  # for testing only
-    return im
+    return cast(MpoImagePlugin.MpoImageFile, Image.open(out))
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_sanity(test_file) -> None:
+def test_sanity(test_file: str) -> None:
     with Image.open(test_file) as im:
         im.load()
         assert im.mode == "RGB"
@@ -70,7 +68,7 @@ def test_context_manager() -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_app(test_file) -> None:
+def test_app(test_file: str) -> None:
     # Test APP/COM reader (@PIL135)
     with Image.open(test_file) as im:
         assert im.applist[0][0] == "APP1"
@@ -82,7 +80,7 @@ def test_app(test_file) -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_exif(test_file) -> None:
+def test_exif(test_file: str) -> None:
     with Image.open(test_file) as im_original:
         im_reloaded = roundtrip(im_original, save_all=True, exif=im_original.getexif())
 
@@ -95,7 +93,7 @@ def test_exif(test_file) -> None:
 
 def test_frame_size() -> None:
     # This image has been hexedited to contain a different size
-    # in the EXIF data of the second frame
+    # in the SOF marker of the second frame
     with Image.open("Tests/images/sugarshack_frame_size.mpo") as im:
         assert im.size == (640, 480)
 
@@ -143,7 +141,7 @@ def test_reload_exif_after_seek() -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_mp(test_file) -> None:
+def test_mp(test_file: str) -> None:
     with Image.open(test_file) as im:
         mpinfo = im._getmp()
         assert mpinfo[45056] == b"0100"
@@ -168,7 +166,7 @@ def test_mp_no_data() -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_mp_attribute(test_file) -> None:
+def test_mp_attribute(test_file: str) -> None:
     with Image.open(test_file) as im:
         mpinfo = im._getmp()
     for frame_number, mpentry in enumerate(mpinfo[0xB002]):
@@ -185,7 +183,7 @@ def test_mp_attribute(test_file) -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_seek(test_file) -> None:
+def test_seek(test_file: str) -> None:
     with Image.open(test_file) as im:
         assert im.tell() == 0
         # prior to first image raises an error, both blatant and borderline
@@ -229,7 +227,7 @@ def test_eoferror() -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_image_grab(test_file) -> None:
+def test_image_grab(test_file: str) -> None:
     with Image.open(test_file) as im:
         assert im.tell() == 0
         im0 = im.tobytes()
@@ -244,7 +242,7 @@ def test_image_grab(test_file) -> None:
 
 
 @pytest.mark.parametrize("test_file", test_files)
-def test_save(test_file) -> None:
+def test_save(test_file: str) -> None:
     with Image.open(test_file) as im:
         assert im.tell() == 0
         jpg0 = roundtrip(im)

Tests/test_file_msp.py

@@ -52,7 +52,7 @@ def test_open_windows_v1() -> None:
         assert isinstance(im, MspImagePlugin.MspImageFile)
 
 
-def _assert_file_image_equal(source_path, target_path) -> None:
+def _assert_file_image_equal(source_path: str, target_path: str) -> None:
     with Image.open(source_path) as im:
         assert_image_equal_tofile(im, target_path)
 

Tests/test_file_palm.py

@@ -11,7 +11,7 @@ from PIL import Image
 from .helper import assert_image_equal, hopper, magick_command
 
 
-def helper_save_as_palm(tmp_path: Path, mode) -> None:
+def helper_save_as_palm(tmp_path: Path, mode: str) -> None:
     # Arrange
     im = hopper(mode)
     outfile = str(tmp_path / ("temp_" + mode + ".palm"))
@@ -24,7 +24,7 @@ def helper_save_as_palm(tmp_path: Path, mode) -> None:
     assert os.path.getsize(outfile) > 0
 
 
-def open_with_magick(magick, tmp_path: Path, f):
+def open_with_magick(magick: list[str], tmp_path: Path, f: str) -> Image.Image:
     outfile = str(tmp_path / "temp.png")
     rc = subprocess.call(
         magick + [f, outfile], stdout=subprocess.DEVNULL, stderr=subprocess.STDOUT
@@ -33,7 +33,7 @@ def open_with_magick(magick, tmp_path: Path, f):
     return Image.open(outfile)
 
 
-def roundtrip(tmp_path: Path, mode) -> None:
+def roundtrip(tmp_path: Path, mode: str) -> None:
     magick = magick_command()
     if not magick:
         return
@@ -66,6 +66,6 @@ def test_p_mode(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("mode", ("L", "RGB"))
-def test_oserror(tmp_path: Path, mode) -> None:
+def test_oserror(tmp_path: Path, mode: str) -> None:
     with pytest.raises(OSError):
         helper_save_as_palm(tmp_path, mode)

Tests/test_file_pcx.py

@@ -9,7 +9,7 @@ from PIL import Image, ImageFile, PcxImagePlugin
 from .helper import assert_image_equal, hopper
 
 
-def _roundtrip(tmp_path: Path, im) -> None:
+def _roundtrip(tmp_path: Path, im: Image.Image) -> None:
     f = str(tmp_path / "temp.pcx")
     im.save(f)
     with Image.open(f) as im2:
@@ -44,7 +44,7 @@ def test_invalid_file() -> None:
 
 
 @pytest.mark.parametrize("mode", ("1", "L", "P", "RGB"))
-def test_odd(tmp_path: Path, mode) -> None:
+def test_odd(tmp_path: Path, mode: str) -> None:
     # See issue #523, odd sized images should have a stride that's even.
     # Not that ImageMagick or GIMP write PCX that way.
     # We were not handling properly.
@@ -89,7 +89,7 @@ def test_large_count(tmp_path: Path) -> None:
     _roundtrip(tmp_path, im)
 
 
-def _test_buffer_overflow(tmp_path: Path, im, size: int = 1024) -> None:
+def _test_buffer_overflow(tmp_path: Path, im: Image.Image, size: int = 1024) -> None:
     _last = ImageFile.MAXBLOCK
     ImageFile.MAXBLOCK = size
     try:

Tests/test_file_pdf.py

@@ -6,6 +6,7 @@ import os.path
 import tempfile
 import time
 from pathlib import Path
+from typing import Any, Generator
 
 import pytest
 
@@ -14,7 +15,7 @@ from PIL import Image, PdfParser, features
 from .helper import hopper, mark_if_feature_version, skip_unless_feature
 
 
-def helper_save_as_pdf(tmp_path: Path, mode, **kwargs):
+def helper_save_as_pdf(tmp_path: Path, mode: str, **kwargs: Any) -> str:
     # Arrange
     im = hopper(mode)
     outfile = str(tmp_path / ("temp_" + mode + ".pdf"))
@@ -41,13 +42,13 @@ def helper_save_as_pdf(tmp_path: Path, mode, **kwargs):
 
 
 @pytest.mark.parametrize("mode", ("L", "P", "RGB", "CMYK"))
-def test_save(tmp_path: Path, mode) -> None:
+def test_save(tmp_path: Path, mode: str) -> None:
     helper_save_as_pdf(tmp_path, mode)
 
 
 @skip_unless_feature("jpg_2000")
 @pytest.mark.parametrize("mode", ("LA", "RGBA"))
-def test_save_alpha(tmp_path: Path, mode) -> None:
+def test_save_alpha(tmp_path: Path, mode: str) -> None:
     helper_save_as_pdf(tmp_path, mode)
 
 
@@ -112,7 +113,7 @@ def test_resolution(tmp_path: Path) -> None:
         {"dpi": (75, 150), "resolution": 200},
     ),
 )
-def test_dpi(params, tmp_path: Path) -> None:
+def test_dpi(params: dict[str, int | tuple[int, int]], tmp_path: Path) -> None:
     im = hopper()
 
     outfile = str(tmp_path / "temp.pdf")
@@ -156,7 +157,7 @@ def test_save_all(tmp_path: Path) -> None:
         assert os.path.getsize(outfile) > 0
 
         # Test appending using a generator
-        def im_generator(ims):
+        def im_generator(ims: list[Image.Image]) -> Generator[Image.Image, None, None]:
             yield from ims
 
         im.save(outfile, save_all=True, append_images=im_generator(ims))
@@ -226,7 +227,7 @@ def test_pdf_append_fails_on_nonexistent_file() -> None:
             im.save(os.path.join(temp_dir, "nonexistent.pdf"), append=True)
 
 
-def check_pdf_pages_consistency(pdf) -> None:
+def check_pdf_pages_consistency(pdf: PdfParser.PdfParser) -> None:
     pages_info = pdf.read_indirect(pdf.pages_ref)
     assert b"Parent" not in pages_info
     assert b"Kids" in pages_info
@@ -339,7 +340,7 @@ def test_pdf_append_to_bytesio() -> None:
 @pytest.mark.timeout(1)
 @pytest.mark.skipif("PILLOW_VALGRIND_TEST" in os.environ, reason="Valgrind is slower")
 @pytest.mark.parametrize("newline", (b"\r", b"\n"))
-def test_redos(newline) -> None:
+def test_redos(newline: bytes) -> None:
     malicious = b" trailer<<>>" + newline * 3456
 
     # This particular exception isn't relevant here.

Tests/test_file_png.py

@@ -6,6 +6,8 @@ import warnings
 import zlib
 from io import BytesIO
 from pathlib import Path
+from types import ModuleType
+from typing import Any, cast
 
 import pytest
 
@@ -22,6 +24,7 @@ from .helper import (
     skip_unless_feature,
 )
 
+ElementTree: ModuleType | None
 try:
     from defusedxml import ElementTree
 except ImportError:
@@ -36,7 +39,7 @@ TEST_PNG_FILE = "Tests/images/hopper.png"
 MAGIC = PngImagePlugin._MAGIC
 
 
-def chunk(cid, *data):
+def chunk(cid: bytes, *data: bytes) -> bytes:
     test_file = BytesIO()
     PngImagePlugin.putchunk(*(test_file, cid) + data)
     return test_file.getvalue()
@@ -52,20 +55,20 @@ HEAD = MAGIC + IHDR
 TAIL = IDAT + IEND
 
 
-def load(data):
+def load(data: bytes) -> Image.Image:
     return Image.open(BytesIO(data))
 
 
-def roundtrip(im, **options):
+def roundtrip(im: Image.Image, **options: Any) -> PngImagePlugin.PngImageFile:
     out = BytesIO()
     im.save(out, "PNG", **options)
     out.seek(0)
-    return Image.open(out)
+    return cast(PngImagePlugin.PngImageFile, Image.open(out))
 
 
 @skip_unless_feature("zlib")
 class TestFilePng:
-    def get_chunks(self, filename):
+    def get_chunks(self, filename: str) -> list[bytes]:
         chunks = []
         with open(filename, "rb") as fp:
             fp.read(8)
@@ -99,7 +102,7 @@ class TestFilePng:
             im = hopper(mode)
             im.save(test_file)
             with Image.open(test_file) as reloaded:
-                if mode in ("I;16", "I;16B"):
+                if mode in ("I", "I;16B"):
                     reloaded = reloaded.convert(mode)
                 assert_image_equal(reloaded, im)
 
@@ -301,8 +304,8 @@ class TestFilePng:
         assert im.getcolors() == [(100, (0, 0, 0, 0))]
 
     def test_save_grayscale_transparency(self, tmp_path: Path) -> None:
-        for mode, num_transparent in {"1": 1994, "L": 559, "I": 559}.items():
-            in_file = "Tests/images/" + mode.lower() + "_trns.png"
+        for mode, num_transparent in {"1": 1994, "L": 559, "I;16": 559}.items():
+            in_file = "Tests/images/" + mode.split(";")[0].lower() + "_trns.png"
             with Image.open(in_file) as im:
                 assert im.mode == mode
                 assert im.info["transparency"] == 255
@@ -436,7 +439,7 @@ class TestFilePng:
     def test_unicode_text(self) -> None:
         # Check preservation of non-ASCII characters
 
-        def rt_text(value) -> None:
+        def rt_text(value: str) -> None:
             im = Image.new("RGB", (32, 32))
             info = PngImagePlugin.PngInfo()
             info.add_text("Text", value)
@@ -616,6 +619,10 @@ class TestFilePng:
         with Image.open("Tests/images/hopper_idat_after_image_end.png") as im:
             assert im.text == {"TXT": "VALUE", "ZIP": "VALUE"}
 
+    def test_unknown_compression_method(self) -> None:
+        with pytest.raises(SyntaxError, match="Unknown compression method"):
+            PngImagePlugin.PngImageFile("Tests/images/unknown_compression_method.png")
+
     def test_padded_idat(self) -> None:
         # This image has been manually hexedited
         # so that the IDAT chunk has padding at the end
@@ -636,7 +643,7 @@ class TestFilePng:
     @pytest.mark.parametrize(
         "cid", (b"IHDR", b"sRGB", b"pHYs", b"acTL", b"fcTL", b"fdAT")
     )
-    def test_truncated_chunks(self, cid) -> None:
+    def test_truncated_chunks(self, cid: bytes) -> None:
         fp = BytesIO()
         with PngImagePlugin.PngStream(fp) as png:
             with pytest.raises(ValueError):
@@ -755,7 +762,7 @@ class TestFilePng:
                 im.seek(1)
 
     @pytest.mark.parametrize("buffer", (True, False))
-    def test_save_stdout(self, buffer) -> None:
+    def test_save_stdout(self, buffer: bool) -> None:
         old_stdout = sys.stdout
 
         if buffer:
@@ -780,6 +787,18 @@ class TestFilePng:
         with Image.open(mystdout) as reloaded:
             assert_image_equal_tofile(reloaded, TEST_PNG_FILE)
 
+    def test_truncated_end_chunk(self) -> None:
+        with Image.open("Tests/images/truncated_end_chunk.png") as im:
+            with pytest.raises(OSError):
+                im.load()
+
+        ImageFile.LOAD_TRUNCATED_IMAGES = True
+        try:
+            with Image.open("Tests/images/truncated_end_chunk.png") as im:
+                assert_image_equal_tofile(im, "Tests/images/hopper.png")
+        finally:
+            ImageFile.LOAD_TRUNCATED_IMAGES = False
+
 
 @pytest.mark.skipif(is_win32(), reason="Requires Unix or macOS")
 @skip_unless_feature("zlib")

Tests/test_file_ppm.py

@@ -70,7 +70,9 @@ def test_sanity() -> None:
         ),
     ),
 )
-def test_arbitrary_maxval(data, mode, pixels) -> None:
+def test_arbitrary_maxval(
+    data: bytes, mode: str, pixels: tuple[int | tuple[int, int, int], ...]
+) -> None:
     fp = BytesIO(data)
     with Image.open(fp) as im:
         assert im.size == (3, 1)
@@ -86,7 +88,7 @@ def test_16bit_pgm() -> None:
         assert im.size == (20, 100)
         assert im.get_format_mimetype() == "image/x-portable-graymap"
 
-        assert_image_equal_tofile(im, "Tests/images/16_bit_binary_pgm.png")
+        assert_image_equal_tofile(im, "Tests/images/16_bit_binary_pgm.tiff")
 
 
 def test_16bit_pgm_write(tmp_path: Path) -> None:
@@ -139,7 +141,7 @@ def test_pfm_big_endian(tmp_path: Path) -> None:
         b"Pf 1 1 -0.0 \0\0\0\0",
     ],
 )
-def test_pfm_invalid(data) -> None:
+def test_pfm_invalid(data: bytes) -> None:
     with pytest.raises(ValueError):
         with Image.open(BytesIO(data)):
             pass
@@ -162,7 +164,7 @@ def test_pfm_invalid(data) -> None:
         ),
     ),
 )
-def test_plain(plain_path, raw_path) -> None:
+def test_plain(plain_path: str, raw_path: str) -> None:
     with Image.open(plain_path) as im:
         assert_image_equal_tofile(im, raw_path)
 
@@ -186,7 +188,9 @@ def test_16bit_plain_pgm() -> None:
         (b"P3\n2 2\n255", b"0 0 0 001 1 1 2 2 2 255 255 255", 10**6),
     ),
 )
-def test_plain_data_with_comment(tmp_path: Path, header, data, comment_count) -> None:
+def test_plain_data_with_comment(
+    tmp_path: Path, header: bytes, data: bytes, comment_count: int
+) -> None:
     path1 = str(tmp_path / "temp1.ppm")
     path2 = str(tmp_path / "temp2.ppm")
     comment = b"# comment" * comment_count
@@ -199,7 +203,7 @@ def test_plain_data_with_comment(tmp_path: Path, header, data, comment_count) ->
 
 
 @pytest.mark.parametrize("data", (b"P1\n128 128\n", b"P3\n128 128\n255\n"))
-def test_plain_truncated_data(tmp_path: Path, data) -> None:
+def test_plain_truncated_data(tmp_path: Path, data: bytes) -> None:
     path = str(tmp_path / "temp.ppm")
     with open(path, "wb") as f:
         f.write(data)
@@ -210,7 +214,7 @@ def test_plain_truncated_data(tmp_path: Path, data) -> None:
 
 
 @pytest.mark.parametrize("data", (b"P1\n128 128\n1009", b"P3\n128 128\n255\n100A"))
-def test_plain_invalid_data(tmp_path: Path, data) -> None:
+def test_plain_invalid_data(tmp_path: Path, data: bytes) -> None:
     path = str(tmp_path / "temp.ppm")
     with open(path, "wb") as f:
         f.write(data)
@@ -227,7 +231,7 @@ def test_plain_invalid_data(tmp_path: Path, data) -> None:
         b"P3\n128 128\n255\n012345678910 0",  # token too long
     ),
 )
-def test_plain_ppm_token_too_long(tmp_path: Path, data) -> None:
+def test_plain_ppm_token_too_long(tmp_path: Path, data: bytes) -> None:
     path = str(tmp_path / "temp.ppm")
     with open(path, "wb") as f:
         f.write(data)
@@ -237,13 +241,23 @@ def test_plain_ppm_token_too_long(tmp_path: Path, data) -> None:
             im.load()
 
 
+def test_plain_ppm_value_negative(tmp_path: Path) -> None:
+    path = str(tmp_path / "temp.ppm")
+    with open(path, "wb") as f:
+        f.write(b"P3\n128 128\n255\n-1")
+
+    with Image.open(path) as im:
+        with pytest.raises(ValueError, match="Channel value is negative"):
+            im.load()
+
+
 def test_plain_ppm_value_too_large(tmp_path: Path) -> None:
     path = str(tmp_path / "temp.ppm")
     with open(path, "wb") as f:
         f.write(b"P3\n128 128\n255\n256")
 
     with Image.open(path) as im:
-        with pytest.raises(ValueError):
+        with pytest.raises(ValueError, match="Channel value too large"):
             im.load()
 
 
@@ -313,7 +327,7 @@ def test_not_enough_image_data(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("maxval", (b"0", b"65536"))
-def test_invalid_maxval(maxval, tmp_path: Path) -> None:
+def test_invalid_maxval(maxval: bytes, tmp_path: Path) -> None:
     path = str(tmp_path / "temp.ppm")
     with open(path, "wb") as f:
         f.write(b"P6\n3 1 " + maxval)
@@ -351,7 +365,7 @@ def test_mimetypes(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("buffer", (True, False))
-def test_save_stdout(buffer) -> None:
+def test_save_stdout(buffer: bool) -> None:
     old_stdout = sys.stdout
 
     if buffer:

Tests/test_file_psd.py

@@ -4,7 +4,7 @@ import warnings
 
 import pytest
 
-from PIL import Image, PsdImagePlugin
+from PIL import Image, PsdImagePlugin, UnidentifiedImageError
 
 from .helper import assert_image_equal_tofile, assert_image_similar, hopper, is_pypy
 
@@ -113,6 +113,11 @@ def test_rgba() -> None:
         assert_image_equal_tofile(im, "Tests/images/imagedraw_square.png")
 
 
+def test_negative_top_left_layer() -> None:
+    with Image.open("Tests/images/negative_top_left_layer.psd") as im:
+        assert im.layers[0][2] == (-50, -50, 50, 50)
+
+
 def test_layer_skip() -> None:
     with Image.open("Tests/images/five_channels.psd") as im:
         assert im.n_frames == 1
@@ -147,17 +152,17 @@ def test_combined_larger_than_size() -> None:
     [
         (
             "Tests/images/timeout-1ee28a249896e05b83840ae8140622de8e648ba9.psd",
-            Image.UnidentifiedImageError,
+            UnidentifiedImageError,
         ),
         (
             "Tests/images/timeout-598843abc37fc080ec36a2699ebbd44f795d3a6f.psd",
-            Image.UnidentifiedImageError,
+            UnidentifiedImageError,
         ),
         ("Tests/images/timeout-c8efc3fded6426986ba867a399791bae544f59bc.psd", OSError),
         ("Tests/images/timeout-dedc7a4ebd856d79b4359bbcc79e8ef231ce38f6.psd", OSError),
     ],
 )
-def test_crashes(test_file, raises) -> None:
+def test_crashes(test_file: str, raises) -> None:
     with open(test_file, "rb") as f:
         with pytest.raises(raises):
             with Image.open(f):

Tests/test_file_sgi.py

@@ -72,7 +72,7 @@ def test_invalid_file() -> None:
 
 
 def test_write(tmp_path: Path) -> None:
-    def roundtrip(img) -> None:
+    def roundtrip(img: Image.Image) -> None:
         out = str(tmp_path / "temp.sgi")
         img.save(out, format="sgi")
         assert_image_equal_tofile(img, out)

Tests/test_file_spider.py

@@ -9,7 +9,7 @@ import pytest
 
 from PIL import Image, ImageSequence, SpiderImagePlugin
 
-from .helper import assert_image_equal_tofile, hopper, is_pypy
+from .helper import assert_image_equal, hopper, is_pypy
 
 TEST_FILE = "Tests/images/hopper.spider"
 
@@ -160,4 +160,5 @@ def test_odd_size() -> None:
     im.save(data, format="SPIDER")
 
     data.seek(0)
-    assert_image_equal_tofile(im, data)
+    with Image.open(data) as im2:
+        assert_image_equal(im, im2)

Tests/test_file_tar.py

@@ -19,7 +19,7 @@ TEST_TAR_FILE = "Tests/images/hopper.tar"
         ("jpg", "hopper.jpg", "JPEG"),
     ),
 )
-def test_sanity(codec, test_path, format) -> None:
+def test_sanity(codec: str, test_path: str, format: str) -> None:
     if features.check(codec):
         with TarIO.TarIO(TEST_TAR_FILE, test_path) as tar:
             with Image.open(tar) as im:

Tests/test_file_tga.py

@@ -7,7 +7,7 @@ from pathlib import Path
 
 import pytest
 
-from PIL import Image
+from PIL import Image, UnidentifiedImageError
 
 from .helper import assert_image_equal, assert_image_equal_tofile, hopper
 
@@ -22,8 +22,8 @@ _ORIGIN_TO_ORIENTATION = {"tl": 1, "bl": -1}
 
 
 @pytest.mark.parametrize("mode", _MODES)
-def test_sanity(mode, tmp_path: Path) -> None:
-    def roundtrip(original_im) -> None:
+def test_sanity(mode: str, tmp_path: Path) -> None:
+    def roundtrip(original_im: Image.Image) -> None:
         out = str(tmp_path / "temp.tga")
 
         original_im.save(out, rle=rle)
@@ -65,6 +65,11 @@ def test_sanity(mode, tmp_path: Path) -> None:
                     roundtrip(original_im)
 
 
+def test_palette_depth_8(tmp_path: Path) -> None:
+    with pytest.raises(UnidentifiedImageError):
+        Image.open("Tests/images/p_8.tga")
+
+
 def test_palette_depth_16(tmp_path: Path) -> None:
     with Image.open("Tests/images/p_16.tga") as im:
         assert_image_equal_tofile(im.convert("RGB"), "Tests/images/p_16.png")
@@ -133,6 +138,11 @@ def test_small_palette(tmp_path: Path) -> None:
         assert reloaded.getpalette() == colors
 
 
+def test_missing_palette() -> None:
+    with Image.open("Tests/images/dilation4.lut") as im:
+        assert im.mode == "L"
+
+
 def test_save_wrong_mode(tmp_path: Path) -> None:
     im = hopper("PA")
     out = str(tmp_path / "temp.tga")

Tests/test_file_tiff.py

@@ -4,6 +4,8 @@ import os
 import warnings
 from io import BytesIO
 from pathlib import Path
+from types import ModuleType
+from typing import Generator
 
 import pytest
 
@@ -20,6 +22,7 @@ from .helper import (
     is_win32,
 )
 
+ElementTree: ModuleType | None
 try:
     from defusedxml import ElementTree
 except ImportError:
@@ -110,6 +113,10 @@ class TestFileTiff:
             outfile = str(tmp_path / "temp.tif")
             im.save(outfile, save_all=True, append_images=[im], tiffinfo=im.tag_v2)
 
+    def test_seek_too_large(self):
+        with pytest.raises(ValueError, match="Unable to seek to frame"):
+            Image.open("Tests/images/seek_too_large.tif")
+
     def test_set_legacy_api(self) -> None:
         ifd = TiffImagePlugin.ImageFileDirectory_v2()
         with pytest.raises(Exception) as e:
@@ -156,7 +163,7 @@ class TestFileTiff:
         "resolution_unit, dpi",
         [(None, 72.8), (2, 72.8), (3, 184.912)],
     )
-    def test_load_float_dpi(self, resolution_unit, dpi) -> None:
+    def test_load_float_dpi(self, resolution_unit: int | None, dpi: float) -> None:
         with Image.open(
             "Tests/images/hopper_float_dpi_" + str(resolution_unit) + ".tif"
         ) as im:
@@ -284,7 +291,7 @@ class TestFileTiff:
             ("Tests/images/multipage.tiff", 3),
         ),
     )
-    def test_n_frames(self, path, n_frames) -> None:
+    def test_n_frames(self, path: str, n_frames: int) -> None:
         with Image.open(path) as im:
             assert im.n_frames == n_frames
             assert im.is_animated == (n_frames != 1)
@@ -402,7 +409,7 @@ class TestFileTiff:
             assert len_before == len_after + 1
 
     @pytest.mark.parametrize("legacy_api", (False, True))
-    def test_load_byte(self, legacy_api) -> None:
+    def test_load_byte(self, legacy_api: bool) -> None:
         ifd = TiffImagePlugin.ImageFileDirectory_v2()
         data = b"abc"
         ret = ifd.load_byte(data, legacy_api)
@@ -431,7 +438,7 @@ class TestFileTiff:
             assert 0x8825 in im.tag_v2
 
     def test_exif(self, tmp_path: Path) -> None:
-        def check_exif(exif) -> None:
+        def check_exif(exif: Image.Exif) -> None:
             assert sorted(exif.keys()) == [
                 256,
                 257,
@@ -511,7 +518,7 @@ class TestFileTiff:
             assert im.getexif()[273] == (1408, 1907)
 
     @pytest.mark.parametrize("mode", ("1", "L"))
-    def test_photometric(self, mode, tmp_path: Path) -> None:
+    def test_photometric(self, mode: str, tmp_path: Path) -> None:
         filename = str(tmp_path / "temp.tif")
         im = hopper(mode)
         im.save(filename, tiffinfo={262: 0})
@@ -620,6 +627,7 @@ class TestFileTiff:
         im.save(outfile, tiffinfo={278: 256})
 
         with Image.open(outfile) as im:
+            assert isinstance(im, TiffImagePlugin.TiffImageFile)
             assert im.tag_v2[278] == 256
 
     def test_strip_raw(self) -> None:
@@ -660,7 +668,7 @@ class TestFileTiff:
                 assert_image_equal_tofile(reloaded, infile)
 
     @pytest.mark.parametrize("mode", ("P", "PA"))
-    def test_palette(self, mode, tmp_path: Path) -> None:
+    def test_palette(self, mode: str, tmp_path: Path) -> None:
         outfile = str(tmp_path / "temp.tif")
 
         im = hopper(mode)
@@ -689,7 +697,7 @@ class TestFileTiff:
             assert reread.n_frames == 3
 
         # Test appending using a generator
-        def im_generator(ims):
+        def im_generator(ims: list[Image.Image]) -> Generator[Image.Image, None, None]:
             yield from ims
 
         mp = BytesIO()
@@ -860,7 +868,7 @@ class TestFileTiff:
         ],
     )
     @pytest.mark.timeout(2)
-    def test_oom(self, test_file) -> None:
+    def test_oom(self, test_file: str) -> None:
         with pytest.raises(UnidentifiedImageError):
             with pytest.warns(UserWarning):
                 with Image.open(test_file):

Tests/test_file_tiff_metadata.py

@@ -189,7 +189,9 @@ def test_iptc(tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("value, expected", ((b"test", "test"), (1, "1")))
-def test_writing_other_types_to_ascii(value, expected, tmp_path: Path) -> None:
+def test_writing_other_types_to_ascii(
+    value: bytes | int, expected: str, tmp_path: Path
+) -> None:
     info = TiffImagePlugin.ImageFileDirectory_v2()
 
     tag = TiffTags.TAGS_V2[271]
@@ -206,7 +208,7 @@ def test_writing_other_types_to_ascii(value, expected, tmp_path: Path) -> None:
 
 
 @pytest.mark.parametrize("value", (1, IFDRational(1)))
-def test_writing_other_types_to_bytes(value, tmp_path: Path) -> None:
+def test_writing_other_types_to_bytes(value: int | IFDRational, tmp_path: Path) -> None:
     im = hopper()
     info = TiffImagePlugin.ImageFileDirectory_v2()
 
@@ -222,14 +224,17 @@ def test_writing_other_types_to_bytes(value, tmp_path: Path) -> None:
         assert reloaded.tag_v2[700] == b"\x01"
 
 
-def test_writing_other_types_to_undefined(tmp_path: Path) -> None:
+@pytest.mark.parametrize("value", (1, IFDRational(1)))
+def test_writing_other_types_to_undefined(
+    value: int | IFDRational, tmp_path: Path
+) -> None:
     im = hopper()
     info = TiffImagePlugin.ImageFileDirectory_v2()
 
     tag = TiffTags.TAGS_V2[33723]
     assert tag.type == TiffTags.UNDEFINED
 
-    info[33723] = 1
+    info[33723] = value
 
     out = str(tmp_path / "temp.tiff")
     im.save(out, tiffinfo=info)

Tests/test_file_webp_alpha.py

@@ -151,3 +151,15 @@ def test_write_unsupported_mode_PA(tmp_path: Path) -> None:
             target = im.convert("RGBA")
 
         assert_image_similar(image, target, 25.0)
+
+
+def test_alpha_quality(tmp_path: Path) -> None:
+    with Image.open("Tests/images/transparent.png") as im:
+        out = str(tmp_path / "temp.webp")
+        im.save(out)
+
+        out_quality = str(tmp_path / "quality.webp")
+        im.save(out_quality, alpha_quality=50)
+        with Image.open(out) as reloaded:
+            with Image.open(out_quality) as reloaded_quality:
+                assert reloaded.tobytes() != reloaded_quality.tobytes()

Tests/test_file_webp_animated.py

@@ -188,3 +188,21 @@ def test_seek_errors() -> None:
 
         with pytest.raises(EOFError):
             im.seek(42)
+
+
+def test_alpha_quality(tmp_path: Path) -> None:
+    with Image.open("Tests/images/transparent.png") as im:
+        first_frame = Image.new("L", im.size)
+
+        out = str(tmp_path / "temp.webp")
+        first_frame.save(out, save_all=True, append_images=[im])
+
+        out_quality = str(tmp_path / "quality.webp")
+        first_frame.save(
+            out_quality, save_all=True, append_images=[im], alpha_quality=50
+        )
+        with Image.open(out) as reloaded:
+            reloaded.seek(1)
+            with Image.open(out_quality) as reloaded_quality:
+                reloaded_quality.seek(1)
+                assert reloaded.tobytes() != reloaded_quality.tobytes()

Tests/test_file_webp_metadata.py

@@ -2,6 +2,7 @@ from __future__ import annotations
 
 from io import BytesIO
 from pathlib import Path
+from types import ModuleType
 
 import pytest
 
@@ -14,6 +15,7 @@ pytestmark = [
     skip_unless_feature("webp_mux"),
 ]
 
+ElementTree: ModuleType | None
 try:
     from defusedxml import ElementTree
 except ImportError:

Tests/test_font_leaks.py

@@ -1,8 +1,10 @@
 from __future__ import annotations
 
-from PIL import Image, ImageDraw, ImageFont
+from PIL import Image, ImageDraw, ImageFont, _util
 
-from .helper import PillowLeakTestCase, skip_unless_feature
+from .helper import PillowLeakTestCase, features, skip_unless_feature
+
+original_core = ImageFont.core
 
 
 class TestTTypeFontLeak(PillowLeakTestCase):
@@ -31,5 +33,11 @@ class TestDefaultFontLeak(TestTTypeFontLeak):
     mem_limit = 1024  # k
 
     def test_leak(self) -> None:
-        default_font = ImageFont.load_default()
+        if features.check_module("freetype2"):
+            ImageFont.core = _util.DeferredError(ImportError)
+        try:
+            default_font = ImageFont.load_default()
+        finally:
+            ImageFont.core = original_core
+
         self._test_font(default_font)

Tests/test_format_hsv.py

@@ -2,21 +2,18 @@ from __future__ import annotations
 
 import colorsys
 import itertools
+from typing import Callable
 
 from PIL import Image
 
 from .helper import assert_image_similar, hopper
 
 
-def int_to_float(i):
+def int_to_float(i: int) -> float:
     return i / 255
 
 
-def str_to_float(i):
-    return ord(i) / 255
-
-
-def tuple_to_ints(tp):
+def tuple_to_ints(tp: tuple[float, float, float]) -> tuple[int, int, int]:
     x, y, z = tp
     return int(x * 255.0), int(y * 255.0), int(z * 255.0)
 
@@ -25,7 +22,7 @@ def test_sanity() -> None:
     Image.new("HSV", (100, 100))
 
 
-def wedge():
+def wedge() -> Image.Image:
     w = Image._wedge()
     w90 = w.rotate(90)
 
@@ -49,7 +46,11 @@ def wedge():
     return img
 
 
-def to_xxx_colorsys(im, func, mode):
+def to_xxx_colorsys(
+    im: Image.Image,
+    func: Callable[[float, float, float], tuple[float, float, float]],
+    mode: str,
+) -> Image.Image:
     # convert the hard way using the library colorsys routines.
 
     (r, g, b) = im.split()
@@ -70,11 +71,11 @@ def to_xxx_colorsys(im, func, mode):
     return hsv
 
 
-def to_hsv_colorsys(im):
+def to_hsv_colorsys(im: Image.Image) -> Image.Image:
     return to_xxx_colorsys(im, colorsys.rgb_to_hsv, "HSV")
 
 
-def to_rgb_colorsys(im):
+def to_rgb_colorsys(im: Image.Image) -> Image.Image:
     return to_xxx_colorsys(im, colorsys.hsv_to_rgb, "RGB")
 
 

Tests/test_image.py

@@ -8,6 +8,7 @@ import sys
 import tempfile
 import warnings
 from pathlib import Path
+from typing import IO
 
 import pytest
 
@@ -15,6 +16,7 @@ from PIL import (
     ExifTags,
     Image,
     ImageDraw,
+    ImageFile,
     ImagePalette,
     UnidentifiedImageError,
     features,
@@ -31,41 +33,43 @@ from .helper import (
     skip_unless_feature,
 )
 
+# name, pixel size
+image_modes = (
+    ("1", 1),
+    ("L", 1),
+    ("LA", 4),
+    ("La", 4),
+    ("P", 1),
+    ("PA", 4),
+    ("F", 4),
+    ("I", 4),
+    ("I;16", 2),
+    ("I;16L", 2),
+    ("I;16B", 2),
+    ("I;16N", 2),
+    ("RGB", 4),
+    ("RGBA", 4),
+    ("RGBa", 4),
+    ("RGBX", 4),
+    ("BGR;15", 2),
+    ("BGR;16", 2),
+    ("BGR;24", 3),
+    ("CMYK", 4),
+    ("YCbCr", 4),
+    ("HSV", 4),
+    ("LAB", 4),
+)
+
+image_mode_names = [name for name, _ in image_modes]
+
 
 class TestImage:
-    @pytest.mark.parametrize(
-        "mode",
-        (
-            "1",
-            "P",
-            "PA",
-            "L",
-            "LA",
-            "La",
-            "F",
-            "I",
-            "I;16",
-            "I;16L",
-            "I;16B",
-            "I;16N",
-            "RGB",
-            "RGBX",
-            "RGBA",
-            "RGBa",
-            "BGR;15",
-            "BGR;16",
-            "BGR;24",
-            "CMYK",
-            "YCbCr",
-            "LAB",
-            "HSV",
-        ),
-    )
-    def test_image_modes_success(self, mode) -> None:
+    @pytest.mark.parametrize("mode", image_mode_names)
+    def test_image_modes_success(self, mode: str) -> None:
         Image.new(mode, (1, 1))
 
     @pytest.mark.parametrize("mode", ("", "bad", "very very long"))
-    def test_image_modes_fail(self, mode) -> None:
+    def test_image_modes_fail(self, mode: str) -> None:
         with pytest.raises(ValueError) as e:
             Image.new(mode, (1, 1))
         assert str(e.value) == "unrecognized image mode"
@@ -104,7 +108,7 @@ class TestImage:
 
     def test_repr_pretty(self) -> None:
         class Pretty:
-            def text(self, text) -> None:
+            def text(self, text: str) -> None:
                 self.pretty_output = text
 
         im = Image.new("L", (100, 100))
@@ -141,13 +145,13 @@ class TestImage:
         assert im.height == 2
 
         with pytest.raises(AttributeError):
-            im.size = (3, 4)
+            im.size = (3, 4)  # type: ignore[misc]
 
     def test_set_mode(self) -> None:
         im = Image.new("RGB", (1, 1))
 
         with pytest.raises(AttributeError):
-            im.mode = "P"
+            im.mode = "P"  # type: ignore[misc]
 
     def test_invalid_image(self) -> None:
         im = io.BytesIO(b"")
@@ -166,8 +170,6 @@ class TestImage:
                 pass
 
     def test_pathlib(self, tmp_path: Path) -> None:
-        from PIL.Image import Path
-
         with Image.open(Path("Tests/images/multipage-mmap.tiff")) as im:
             assert im.mode == "P"
             assert im.size == (10, 10)
@@ -188,7 +190,9 @@ class TestImage:
         temp_file = str(tmp_path / "temp.jpg")
 
         class FP:
-            def write(self, b) -> None:
+            name: str
+
+            def write(self, b: bytes) -> None:
                 pass
 
         fp = FP()
@@ -542,7 +546,7 @@ class TestImage:
         "PILLOW_VALGRIND_TEST" in os.environ, reason="Valgrind is slower"
     )
     @pytest.mark.parametrize("size", ((0, 100000000), (100000000, 0)))
-    def test_empty_image(self, size) -> None:
+    def test_empty_image(self, size: tuple[int, int]) -> None:
         Image.new("RGB", size)
 
     def test_storage_neg(self) -> None:
@@ -569,7 +573,7 @@ class TestImage:
             Image.linear_gradient(wrong_mode)
 
     @pytest.mark.parametrize("mode", ("L", "P", "I", "F"))
-    def test_linear_gradient(self, mode) -> None:
+    def test_linear_gradient(self, mode: str) -> None:
         # Arrange
         target_file = "Tests/images/linear_gradient.png"
 
@@ -594,7 +598,7 @@ class TestImage:
             Image.radial_gradient(wrong_mode)
 
     @pytest.mark.parametrize("mode", ("L", "P", "I", "F"))
-    def test_radial_gradient(self, mode) -> None:
+    def test_radial_gradient(self, mode: str) -> None:
         # Arrange
         target_file = "Tests/images/radial_gradient.png"
 
@@ -669,7 +673,11 @@ class TestImage:
         blank_p.palette = None
         blank_pa.palette = None
 
-        def _make_new(base_image, image, palette_result=None) -> None:
+        def _make_new(
+            base_image: Image.Image,
+            image: Image.Image,
+            palette_result: ImagePalette.ImagePalette | None = None,
+        ) -> None:
             new_image = base_image._new(image.im)
             assert new_image.mode == image.mode
             assert new_image.size == image.size
@@ -684,15 +692,18 @@ class TestImage:
         _make_new(im, blank_p, ImagePalette.ImagePalette())
         _make_new(im, blank_pa, ImagePalette.ImagePalette())
 
-    def test_p_from_rgb_rgba(self) -> None:
-        for mode, color in [
+    @pytest.mark.parametrize(
+        "mode, color",
+        (
             ("RGB", "#DDEEFF"),
             ("RGB", (221, 238, 255)),
             ("RGBA", (221, 238, 255, 255)),
-        ]:
-            im = Image.new("P", (100, 100), color)
-            expected = Image.new(mode, (100, 100), color)
-            assert_image_equal(im.convert(mode), expected)
+        ),
+    )
+    def test_p_from_rgb_rgba(self, mode: str, color: str | tuple[int, ...]) -> None:
+        im = Image.new("P", (100, 100), color)
+        expected = Image.new(mode, (100, 100), color)
+        assert_image_equal(im.convert(mode), expected)
 
     def test_no_resource_warning_on_save(self, tmp_path: Path) -> None:
         # https://github.com/python-pillow/Pillow/issues/835
@@ -717,7 +728,7 @@ class TestImage:
     def test_load_on_nonexclusive_multiframe(self) -> None:
         with open("Tests/images/frozenpond.mpo", "rb") as fp:
 
-            def act(fp) -> None:
+            def act(fp: IO[bytes]) -> None:
                 im = Image.open(fp)
                 im.load()
 
@@ -910,12 +921,12 @@ class TestImage:
                 assert exif.get_ifd(0xA005)
 
     @pytest.mark.parametrize("size", ((1, 0), (0, 1), (0, 0)))
-    def test_zero_tobytes(self, size) -> None:
+    def test_zero_tobytes(self, size: tuple[int, int]) -> None:
         im = Image.new("RGB", size)
         assert im.tobytes() == b""
 
     @pytest.mark.parametrize("size", ((1, 0), (0, 1), (0, 0)))
-    def test_zero_frombytes(self, size) -> None:
+    def test_zero_frombytes(self, size: tuple[int, int]) -> None:
         Image.frombytes("RGB", size, b"")
 
         im = Image.new("RGB", size)
@@ -1000,7 +1011,7 @@ class TestImage:
             "01r_00.pcx",
         ],
     )
-    def test_overrun(self, path) -> None:
+    def test_overrun(self, path: str) -> None:
         """For overrun completeness, test as:
         valgrind pytest -qq Tests/test_image.py::TestImage::test_overrun | grep decode.c
         """
@@ -1027,7 +1038,7 @@ class TestImage:
             pass
         assert not hasattr(im, "fp")
 
-    def test_close_graceful(self, caplog) -> None:
+    def test_close_graceful(self, caplog: pytest.LogCaptureFixture) -> None:
         with Image.open("Tests/images/hopper.jpg") as im:
             copy = im.copy()
             with caplog.at_level(logging.DEBUG):
@@ -1037,25 +1048,49 @@ class TestImage:
             assert im.fp is None
 
 
-class MockEncoder:
+class TestImageBytes:
+    @pytest.mark.parametrize("mode", image_mode_names)
+    def test_roundtrip_bytes_constructor(self, mode: str) -> None:
+        im = hopper(mode)
+        source_bytes = im.tobytes()
+
+        reloaded = Image.frombytes(mode, im.size, source_bytes)
+        assert reloaded.tobytes() == source_bytes
+
+    @pytest.mark.parametrize("mode", image_mode_names)
+    def test_roundtrip_bytes_method(self, mode: str) -> None:
+        im = hopper(mode)
+        source_bytes = im.tobytes()
+
+        reloaded = Image.new(mode, im.size)
+        reloaded.frombytes(source_bytes)
+        assert reloaded.tobytes() == source_bytes
+
+    @pytest.mark.parametrize(("mode", "pixelsize"), image_modes)
+    def test_getdata_putdata(self, mode: str, pixelsize: int) -> None:
+        im = Image.new(mode, (2, 2))
+        source_bytes = bytes(range(im.width * im.height * pixelsize))
+        im.frombytes(source_bytes)
+
+        reloaded = Image.new(mode, im.size)
+        reloaded.putdata(im.getdata())
+        assert_image_equal(im, reloaded)
+
+
+class MockEncoder(ImageFile.PyEncoder):
     pass
 
 
-def mock_encode(*args):
-    encoder = MockEncoder()
-    encoder.args = args
-    return encoder
-
-
 class TestRegistry:
     def test_encode_registry(self) -> None:
-        Image.register_encoder("MOCK", mock_encode)
+        Image.register_encoder("MOCK", MockEncoder)
         assert "MOCK" in Image.ENCODERS
 
         enc = Image._getencoder("RGB", "MOCK", ("args",), extra=("extra",))
 
         assert isinstance(enc, MockEncoder)
-        assert enc.args == ("RGB", "args", "extra")
+        assert enc.mode == "RGB"
+        assert enc.args == ("args", "extra")
 
     def test_encode_registry_fail(self) -> None:
         with pytest.raises(OSError):

Tests/test_image_access.py

@@ -4,6 +4,7 @@ import os
 import subprocess
 import sys
 import sysconfig
+from types import ModuleType
 
 import pytest
 
@@ -13,6 +14,7 @@ from .helper import assert_image_equal, hopper, is_win32
 
 # CFFI imports pycparser which doesn't support PYTHONOPTIMIZE=2
 # https://github.com/eliben/pycparser/pull/198#issuecomment-317001670
+cffi: ModuleType | None
 if os.environ.get("PYTHONOPTIMIZE") == "2":
     cffi = None
 else:
@@ -23,6 +25,7 @@ else:
     except ImportError:
         cffi = None
 
+numpy: ModuleType | None
 try:
     import numpy
 except ImportError:
@@ -71,9 +74,10 @@ class TestImagePutPixel(AccessTest):
         pix1 = im1.load()
         pix2 = im2.load()
 
-        for x, y in ((0, "0"), ("0", 0)):
-            with pytest.raises(TypeError):
-                pix1[x, y]
+        with pytest.raises(TypeError):
+            pix1[0, "0"]
+        with pytest.raises(TypeError):
+            pix1["0", 0]
 
         for y in range(im1.size[1]):
             for x in range(im1.size[0]):
@@ -123,12 +127,13 @@ class TestImagePutPixel(AccessTest):
         im = hopper()
         pix = im.load()
 
+        assert numpy is not None
         assert pix[numpy.int32(1), numpy.int32(2)] == (18, 20, 59)
 
 
 class TestImageGetPixel(AccessTest):
     @staticmethod
-    def color(mode):
+    def color(mode: str) -> int | tuple[int, ...]:
         bands = Image.getmodebands(mode)
         if bands == 1:
             return 1
@@ -138,12 +143,13 @@ class TestImageGetPixel(AccessTest):
             return (16, 32, 49)
         return tuple(range(1, bands + 1))
 
-    def check(self, mode, expected_color=None) -> None:
+    def check(self, mode: str, expected_color_int: int | None = None) -> None:
         if self._need_cffi_access and mode.startswith("BGR;"):
             pytest.skip("Support not added to deprecated module for BGR;* modes")
 
-        if not expected_color:
-            expected_color = self.color(mode)
+        expected_color = (
+            self.color(mode) if expected_color_int is None else expected_color_int
+        )
 
         # check putpixel
         im = Image.new(mode, (1, 1), None)
@@ -222,7 +228,7 @@ class TestImageGetPixel(AccessTest):
             "YCbCr",
         ),
     )
-    def test_basic(self, mode) -> None:
+    def test_basic(self, mode: str) -> None:
         self.check(mode)
 
     def test_list(self) -> None:
@@ -230,17 +236,15 @@ class TestImageGetPixel(AccessTest):
         assert im.getpixel([0, 0]) == (20, 20, 70)
 
     @pytest.mark.parametrize("mode", ("I;16", "I;16B"))
-    @pytest.mark.parametrize(
-        "expected_color", (2**15 - 1, 2**15, 2**15 + 1, 2**16 - 1)
-    )
-    def test_signedness(self, mode, expected_color) -> None:
+    @pytest.mark.parametrize("expected_color", (2**15 - 1, 2**15, 2**15 + 1, 2**16 - 1))
+    def test_signedness(self, mode: str, expected_color: int) -> None:
         # see https://github.com/python-pillow/Pillow/issues/452
         # pixelaccess is using signed int* instead of uint*
         self.check(mode, expected_color)
 
     @pytest.mark.parametrize("mode", ("P", "PA"))
     @pytest.mark.parametrize("color", ((255, 0, 0), (255, 0, 0, 255)))
-    def test_p_putpixel_rgb_rgba(self, mode, color) -> None:
+    def test_p_putpixel_rgb_rgba(self, mode: str, color: tuple[int, ...]) -> None:
         im = Image.new(mode, (1, 1))
         im.putpixel((0, 0), color)
 
@@ -264,7 +268,7 @@ class TestCffiGetPixel(TestImageGetPixel):
 class TestCffi(AccessTest):
     _need_cffi_access = True
 
-    def _test_get_access(self, im) -> None:
+    def _test_get_access(self, im: Image.Image) -> None:
         """Do we get the same thing as the old pixel access
 
         Using private interfaces, forcing a capi access and
@@ -301,7 +305,7 @@ class TestCffi(AccessTest):
         # im = Image.new('I;32B', (10, 10), 2**10)
         # self._test_get_access(im)
 
-    def _test_set_access(self, im, color) -> None:
+    def _test_set_access(self, im: Image.Image, color: tuple[int, ...] | float) -> None:
         """Are we writing the correct bits into the image?
 
         Using private interfaces, forcing a capi access and
@@ -361,7 +365,7 @@ class TestCffi(AccessTest):
                 assert px[i, 0] == 0
 
     @pytest.mark.parametrize("mode", ("P", "PA"))
-    def test_p_putpixel_rgb_rgba(self, mode) -> None:
+    def test_p_putpixel_rgb_rgba(self, mode: str) -> None:
         for color in ((255, 0, 0), (255, 0, 0, 127 if mode == "PA" else 255)):
             im = Image.new(mode, (1, 1))
             with pytest.warns(DeprecationWarning):
@@ -379,7 +383,7 @@ class TestImagePutPixelError(AccessTest):
     INVALID_TYPES = ["foo", 1.0, None]
 
     @pytest.mark.parametrize("mode", IMAGE_MODES1)
-    def test_putpixel_type_error1(self, mode) -> None:
+    def test_putpixel_type_error1(self, mode: str) -> None:
         im = hopper(mode)
         for v in self.INVALID_TYPES:
             with pytest.raises(TypeError, match="color must be int or tuple"):
@@ -402,14 +406,16 @@ class TestImagePutPixelError(AccessTest):
             ),
         ),
     )
-    def test_putpixel_invalid_number_of_bands(self, mode, band_numbers, match) -> None:
+    def test_putpixel_invalid_number_of_bands(
+        self, mode: str, band_numbers: tuple[int, ...], match: str
+    ) -> None:
         im = hopper(mode)
         for band_number in band_numbers:
             with pytest.raises(TypeError, match=match):
                 im.putpixel((0, 0), (0,) * band_number)
 
     @pytest.mark.parametrize("mode", IMAGE_MODES2)
-    def test_putpixel_type_error2(self, mode) -> None:
+    def test_putpixel_type_error2(self, mode: str) -> None:
         im = hopper(mode)
         for v in self.INVALID_TYPES:
             with pytest.raises(
@@ -418,7 +424,7 @@ class TestImagePutPixelError(AccessTest):
                 im.putpixel((0, 0), v)
 
     @pytest.mark.parametrize("mode", IMAGE_MODES1 + IMAGE_MODES2)
-    def test_putpixel_overflow_error(self, mode) -> None:
+    def test_putpixel_overflow_error(self, mode: str) -> None:
         im = hopper(mode)
         with pytest.raises(OverflowError):
             im.putpixel((0, 0), 2**80)
@@ -430,7 +436,7 @@ class TestEmbeddable:
     def test_embeddable(self) -> None:
         import ctypes
 
-        from setuptools.command.build_ext import new_compiler
+        from setuptools.command import build_ext
 
         with open("embed_pil.c", "w", encoding="utf-8") as fh:
             fh.write(
@@ -459,7 +465,7 @@ int main(int argc, char* argv[])
                 % sys.prefix.replace("\\", "\\\\")
             )
 
-        compiler = new_compiler()
+        compiler = getattr(build_ext, "new_compiler")()
         compiler.add_include_dir(sysconfig.get_config_var("INCLUDEPY"))
 
         libdir = sysconfig.get_config_var("LIBDIR") or sysconfig.get_config_var(
@@ -473,7 +479,7 @@ int main(int argc, char* argv[])
         env["PATH"] = sys.prefix + ";" + env["PATH"]
 
         # do not display the Windows Error Reporting dialog
-        ctypes.windll.kernel32.SetErrorMode(0x0002)
+        getattr(ctypes, "windll").kernel32.SetErrorMode(0x0002)
 
         process = subprocess.Popen(["embed_pil.exe"], env=env)
         process.communicate()

Tests/test_image_array.py

@@ -1,5 +1,7 @@
 from __future__ import annotations
 
+from typing import Any
+
 import pytest
 from packaging.version import parse as parse_version
 
@@ -13,7 +15,7 @@ im = hopper().resize((128, 100))
 
 
 def test_toarray() -> None:
-    def test(mode):
+    def test(mode: str) -> tuple[tuple[int, ...], str, int]:
         ai = numpy.array(im.convert(mode))
         return ai.shape, ai.dtype.str, ai.nbytes
 
@@ -50,14 +52,14 @@ def test_fromarray() -> None:
     class Wrapper:
         """Class with API matching Image.fromarray"""
 
-        def __init__(self, img, arr_params) -> None:
+        def __init__(self, img: Image.Image, arr_params: dict[str, Any]) -> None:
             self.img = img
             self.__array_interface__ = arr_params
 
-        def tobytes(self):
+        def tobytes(self) -> bytes:
             return self.img.tobytes()
 
-    def test(mode):
+    def test(mode: str) -> tuple[str, tuple[int, int], bool]:
         i = im.convert(mode)
         a = numpy.array(i)
         # Make wrapper instance for image, new array interface

Tests/test_image_convert.py

@@ -183,6 +183,14 @@ def test_trns_RGB(tmp_path: Path) -> None:
     assert im_l.info["transparency"] == im_l.getpixel((0, 0))  # undone
     im_l.save(f)
 
+    im_la = im.convert("LA")
+    assert "transparency" not in im_la.info
+    im_la.save(f)
+
+    im_la = im.convert("La")
+    assert "transparency" not in im_la.info
+    assert im_la.getpixel((0, 0)) == (0, 0)
+
     im_p = im.convert("P")
     assert "transparency" in im_p.info
     im_p.save(f)
@@ -191,6 +199,10 @@ def test_trns_RGB(tmp_path: Path) -> None:
     assert "transparency" not in im_rgba.info
     im_rgba.save(f)
 
+    im_rgba = im.convert("RGBa")
+    assert "transparency" not in im_rgba.info
+    assert im_rgba.getpixel((0, 0)) == (0, 0, 0, 0)
+
     im_p = pytest.warns(UserWarning, im.convert, "P", palette=Image.Palette.ADAPTIVE)
     assert "transparency" not in im_p.info
     im_p.save(f)

Tests/test_image_draft.py

@@ -7,7 +7,12 @@ from .helper import fromstring, skip_unless_feature, tostring
 pytestmark = skip_unless_feature("jpg")
 
 
-def draft_roundtrip(in_mode, in_size, req_mode, req_size):
+def draft_roundtrip(
+    in_mode: str,
+    in_size: tuple[int, int],
+    req_mode: str | None,
+    req_size: tuple[int, int] | None,
+) -> Image.Image:
     im = Image.new(in_mode, in_size)
     data = tostring(im, "JPEG")
     im = fromstring(data)

Tests/test_image_entropy.py

@@ -4,7 +4,7 @@ from .helper import hopper
 
 
 def test_entropy() -> None:
-    def entropy(mode):
+    def entropy(mode: str) -> float:
         return hopper(mode).entropy()
 
     assert round(abs(entropy("1") - 0.9138803254693582), 7) == 0

Tests/test_image_filter.py

@@ -36,7 +36,7 @@ from .helper import assert_image_equal, hopper
     ),
 )
 @pytest.mark.parametrize("mode", ("L", "I", "RGB", "CMYK"))
-def test_sanity(filter_to_apply, mode) -> None:
+def test_sanity(filter_to_apply: ImageFilter.Filter, mode: str) -> None:
     im = hopper(mode)
     if mode != "I" or isinstance(filter_to_apply, ImageFilter.BuiltinFilter):
         out = im.filter(filter_to_apply)
@@ -45,7 +45,7 @@ def test_sanity(filter_to_apply, mode) -> None:
 
 
 @pytest.mark.parametrize("mode", ("L", "I", "RGB", "CMYK"))
-def test_sanity_error(mode) -> None:
+def test_sanity_error(mode: str) -> None:
     with pytest.raises(TypeError):
         im = hopper(mode)
         im.filter("hello")
@@ -53,7 +53,7 @@ def test_sanity_error(mode) -> None:
 
 # crashes on small images
 @pytest.mark.parametrize("size", ((1, 1), (2, 2), (3, 3)))
-def test_crash(size) -> None:
+def test_crash(size: tuple[int, int]) -> None:
     im = Image.new("RGB", size)
     im.filter(ImageFilter.SMOOTH)
 
@@ -67,7 +67,10 @@ def test_crash(size) -> None:
         ("RGB", ((4, 0, 0), (0, 0, 0))),
     ),
 )
-def test_modefilter(mode, expected) -> None:
+def test_modefilter(
+    mode: str,
+    expected: tuple[int, int] | tuple[tuple[int, int, int], tuple[int, int, int]],
+) -> None:
     im = Image.new(mode, (3, 3), None)
     im.putdata(list(range(9)))
     # image is:
@@ -90,7 +93,13 @@ def test_modefilter(mode, expected) -> None:
         ("F", (0.0, 4.0, 8.0)),
     ),
 )
-def test_rankfilter(mode, expected) -> None:
+def test_rankfilter(
+    mode: str,
+    expected: (
+        tuple[float, float, float]
+        | tuple[tuple[int, int, int], tuple[int, int, int], tuple[int, int, int]]
+    ),
+) -> None:
     im = Image.new(mode, (3, 3), None)
     im.putdata(list(range(9)))
     # image is:
@@ -106,7 +115,7 @@ def test_rankfilter(mode, expected) -> None:
 @pytest.mark.parametrize(
     "filter", (ImageFilter.MinFilter, ImageFilter.MedianFilter, ImageFilter.MaxFilter)
 )
-def test_rankfilter_error(filter) -> None:
+def test_rankfilter_error(filter: ImageFilter.RankFilter) -> None:
     with pytest.raises(ValueError):
         im = Image.new("P", (3, 3), None)
         im.putdata(list(range(9)))
@@ -137,11 +146,9 @@ def test_kernel_not_enough_coefficients() -> None:
 
 
 @pytest.mark.parametrize("mode", ("L", "LA", "I", "RGB", "CMYK"))
-def test_consistency_3x3(mode) -> None:
+def test_consistency_3x3(mode: str) -> None:
     with Image.open("Tests/images/hopper.bmp") as source:
-        reference_name = "hopper_emboss"
-        reference_name += "_I.png" if mode == "I" else ".bmp"
-        with Image.open("Tests/images/" + reference_name) as reference:
+        with Image.open("Tests/images/hopper_emboss.bmp") as reference:
             kernel = ImageFilter.Kernel(
                 (3, 3),
                 # fmt: off
@@ -151,23 +158,13 @@ def test_consistency_3x3(mode) -> None:
                 # fmt: on
                 0.3,
             )
-            source = source.split() * 2
-            reference = reference.split() * 2
-
-            if mode == "I":
-                source = source[0].convert(mode)
-            else:
-                source = Image.merge(mode, source[: len(mode)])
-            reference = Image.merge(mode, reference[: len(mode)])
             assert_image_equal(source.filter(kernel), reference)
 
 
 @pytest.mark.parametrize("mode", ("L", "LA", "I", "RGB", "CMYK"))
-def test_consistency_5x5(mode) -> None:
+def test_consistency_5x5(mode: str) -> None:
     with Image.open("Tests/images/hopper.bmp") as source:
-        reference_name = "hopper_emboss_more"
-        reference_name += "_I.png" if mode == "I" else ".bmp"
-        with Image.open("Tests/images/" + reference_name) as reference:
+        with Image.open("Tests/images/hopper_emboss_more.bmp") as reference:
             kernel = ImageFilter.Kernel(
                 (5, 5),
                 # fmt: off
@@ -179,14 +176,6 @@ def test_consistency_5x5(mode) -> None:
                 # fmt: on
                 0.3,
             )
-            source = source.split() * 2
-            reference = reference.split() * 2
-
-            if mode == "I":
-                source = source[0].convert(mode)
-            else:
-                source = Image.merge(mode, source[: len(mode)])
-            reference = Image.merge(mode, reference[: len(mode)])
             assert_image_equal(source.filter(kernel), reference)
 
 
@@ -199,7 +188,7 @@ def test_consistency_5x5(mode) -> None:
         (2, -2),
     ),
 )
-def test_invalid_box_blur_filter(radius) -> None:
+def test_invalid_box_blur_filter(radius: int | tuple[int, int]) -> None:
     with pytest.raises(ValueError):
         ImageFilter.BoxBlur(radius)
 

Tests/test_image_frombytes.py

@@ -8,7 +8,7 @@ from .helper import assert_image_equal, hopper
 
 
 @pytest.mark.parametrize("data_type", ("bytes", "memoryview"))
-def test_sanity(data_type) -> None:
+def test_sanity(data_type: str) -> None:
     im1 = hopper()
 
     data = im1.tobytes()