CI: Add a Cygwin run to GitHub Actions

.ci/after_success.sh

@@ -3,7 +3,7 @@
 # gather the coverage data
 python3 -m pip install codecov
 if [[ $MATRIX_DOCKER ]]; then
-  coverage xml --ignore-errors
+  python3 -m coverage xml --ignore-errors
 else
-  coverage xml
+  python3 -m coverage xml
 fi

.ci/build.sh

@@ -2,7 +2,7 @@
 
 set -e
 
-coverage erase
+python3 -m coverage erase
 if [ $(uname) == "Darwin" ]; then
     export CPPFLAGS="-I/usr/local/miniconda/include";
 fi

.ci/install.sh

@@ -13,13 +13,17 @@ aptget_update()
         return 1
     fi
 }
-aptget_update || aptget_update retry || aptget_update retry
+if [[ $(uname) != CYGWIN* ]]; then
+    aptget_update || aptget_update retry || aptget_update retry
+fi
 
 set -e
 
-sudo apt-get -qq install libfreetype6-dev liblcms2-dev python3-tk\
-                         ghostscript libffi-dev libjpeg-turbo-progs libopenjp2-7-dev\
-                         cmake meson imagemagick libharfbuzz-dev libfribidi-dev
+if [[ $(uname) != CYGWIN* ]]; then
+    sudo apt-get -qq install libfreetype6-dev liblcms2-dev python3-tk\
+                             ghostscript libffi-dev libjpeg-turbo-progs libopenjp2-7-dev\
+                             cmake meson imagemagick libharfbuzz-dev libfribidi-dev
+fi
 
 python3 -m pip install --upgrade pip
 python3 -m pip install --upgrade wheel
@@ -32,23 +36,28 @@ python3 -m pip install -U pytest-cov
 python3 -m pip install -U pytest-timeout
 python3 -m pip install pyroma
 python3 -m pip install test-image-results
-# TODO Remove condition when NumPy supports 3.11
-if ! [ "$GHA_PYTHON_VERSION" == "3.11-dev" ]; then python3 -m pip install numpy ; fi
 
-# PyQt6 doesn't support PyPy3
-if [[ $GHA_PYTHON_VERSION == 3.* ]]; then
-    sudo apt-get -qq install libegl1 libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-randr0 libxcb-render-util0 libxkbcommon-x11-0
-    python3 -m pip install pyqt6
-fi
+if [[ $(uname) != CYGWIN* ]]; then
+    # TODO Remove condition when NumPy supports 3.11
+    if ! [ "$GHA_PYTHON_VERSION" == "3.11-dev" ]; then python3 -m pip install numpy ; fi
 
-# webp
-pushd depends && ./install_webp.sh && popd
+    # PyQt6 doesn't support PyPy3
+    if [[ $GHA_PYTHON_VERSION == 3.* ]]; then
+        sudo apt-get -qq install libegl1 libxcb-icccm4 libxcb-image0 libxcb-keysyms1 libxcb-randr0 libxcb-render-util0 libxkbcommon-x11-0
+        python3 -m pip install pyqt6
+    fi
+
+    # webp
+    pushd depends && ./install_webp.sh && popd
 
-# libimagequant
-pushd depends && ./install_imagequant.sh && popd
+    # libimagequant
+    pushd depends && ./install_imagequant.sh && popd
 
-# raqm
-pushd depends && ./install_raqm.sh && popd
+    # raqm
+    pushd depends && ./install_raqm.sh && popd
 
-# extra test images
-pushd depends && ./install_extra_test_images.sh && popd
+    # extra test images
+    pushd depends && ./install_extra_test_images.sh && popd
+else
+    cd depends && ./install_extra_test_images.sh && cd ..
+fi

.github/mergify.yml

@@ -8,6 +8,7 @@ pull_request_rules:
       - status-success=Docker Test Successful
       - status-success=Windows Test Successful
       - status-success=MinGW Test Successful
+      - status-success=Cygwin Test Successful
       - status-success=continuous-integration/appveyor/pr
     actions:
       merge:

.github/workflows/test-cygwin.yml

@@ -0,0 +1,107 @@
+name: Test Cygwin
+
+on: [push, pull_request, workflow_dispatch]
+
+jobs:
+  build:
+    runs-on: windows-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-minor-version: [7, 8, 9]
+
+    timeout-minutes: 40
+
+    name: Python 3.${{ matrix.python-minor-version }}
+
+    steps:
+      - name: Fix line endings
+        run: |
+          git config --global core.autocrlf input
+
+      - name: Checkout Pillow
+        uses: actions/checkout@v3
+
+      - name: Install Cygwin
+        uses: cygwin/cygwin-install-action@v2
+        with:
+          platform: x86_64
+          packages: >
+            ImageMagick gcc-g++ ghostscript jpeg libfreetype-devel
+            libimagequant-devel libjpeg-devel liblapack-devel
+            liblcms2-devel libopenjp2-devel libraqm-devel
+            libtiff-devel libwebp-devel libxcb-devel libxcb-xinerama0
+            make netpbm perl
+            python3${{ matrix.python-minor-version }}-cffi
+            python3${{ matrix.python-minor-version }}-cython
+            python3${{ matrix.python-minor-version }}-devel
+            python3${{ matrix.python-minor-version }}-numpy
+            python3${{ matrix.python-minor-version }}-sip
+            python3${{ matrix.python-minor-version }}-tkinter
+            qt5-devel-tools subversion xorg-server-extra zlib-devel
+
+      - name: Add Lapack to PATH
+        uses: egor-tensin/cleanup-path@v1
+        with:
+          dirs: 'C:\cygwin\bin;C:\cygwin\lib\lapack'
+
+      - name: pip cache
+        uses: actions/cache@v3
+        with:
+          path: 'C:\cygwin\home\runneradmin\.cache\pip'
+          key: ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-${{ hashFiles('.ci/install.sh') }}
+          restore-keys: |
+            ${{ runner.os }}-cygwin-pip3.${{ matrix.python-minor-version }}-
+
+      - name: Build system information
+        run: |
+          dash.exe -c "python3 .github/workflows/system-info.py"
+
+      - name: Install dependencies
+        run: |
+          bash.exe .ci/install.sh
+
+      - name: Install a different NumPy
+        shell: dash.exe -l "{0}"
+        run: |
+          python3 -m pip install -U 'numpy!=1.21.*'
+
+      - name: Build
+        shell: bash.exe -eo pipefail -o igncr "{0}"
+        run: |
+          .ci/build.sh
+
+      - name: Test
+        run: |
+          bash.exe xvfb-run -s '-screen 0 1024x768x24' .ci/test.sh
+
+      - name: Prepare to upload errors
+        if: failure()
+        run: |
+          dash.exe -c "mkdir -p Tests/errors"
+
+      - name: Upload errors
+        uses: actions/upload-artifact@v3
+        if: failure()
+        with:
+          name: errors
+          path: Tests/errors
+
+      - name: After success
+        run: |
+          bash.exe .ci/after_success.sh
+
+      - name: Upload coverage
+        uses: codecov/codecov-action@v3
+        with:
+          file: ./coverage.xml
+          flags: GHA_Cygwin
+          name: Cygwin Python 3.${{ matrix.python-minor-version }}
+
+  success:
+    needs: build
+    runs-on: ubuntu-latest
+    name: Cygwin Test Successful
+    steps:
+      - name: Success
+        run: echo Cygwin Test Successful

README.md

@@ -36,6 +36,9 @@ As of 2019, Pillow development is
             <a href="https://github.com/python-pillow/Pillow/actions/workflows/test-mingw.yml"><img
                 alt="GitHub Actions build status (Test MinGW)"
                 src="https://github.com/python-pillow/Pillow/workflows/Test%20MinGW/badge.svg"></a>
+            <a href="https://github.com/python-pillow/Pillow/actions/workflows/test-cygwin.yml"><img
+                alt="GitHub Actions build status (Test Cygwin)"
+                src="https://github.com/python-pillow/Pillow/workflows/Test%20Cygwin/badge.svg"></a>
             <a href="https://github.com/python-pillow/Pillow/actions/workflows/test-docker.yml"><img
                 alt="GitHub Actions build status (Test Docker)"
                 src="https://github.com/python-pillow/Pillow/workflows/Test%20Docker/badge.svg"></a>

docs/index.rst

@@ -29,6 +29,10 @@ Pillow for enterprise is available via the Tidelift Subscription. `Learn more <h
    :target: https://github.com/python-pillow/Pillow/actions/workflows/test-mingw.yml
    :alt: GitHub Actions build status (Test MinGW)
 
+.. image:: https://github.com/python-pillow/Pillow/workflows/Test%20Cygwin/badge.svg
+   :target: https://github.com/python-pillow/Pillow/actions/workflows/test-cygwin.yml
+   :alt: GitHub Actions build status (Test Cygwin)
+
 .. image:: https://img.shields.io/appveyor/build/python-pillow/Pillow/main.svg?label=Windows%20build
    :target: https://ci.appveyor.com/project/python-pillow/Pillow
    :alt: AppVeyor CI build status (Windows)

docs/installation.rst

@@ -483,7 +483,9 @@ These platforms are built and tested for every change.
 | Windows Server 2022              | 3.7, 3.8, 3.9, 3.10, 3.11, | x86, x86-64         |
 |                                  | PyPy3                      |                     |
 |                                  +----------------------------+---------------------+
-|                                  | 3.9/MinGW                  | x86, x86-64         |
+|                                  | 3.9 (MinGW)                | x86, x86-64         |
+|                                  +----------------------------+---------------------+
+|                                  | 3.7, 3.8, 3.9 (Cygwin)     | x86-64              |
 +----------------------------------+----------------------------+---------------------+
 
 
@@ -568,6 +570,8 @@ These platforms have been reported to work at the versions mentioned.
 +----------------------------------+---------------------------+------------------+--------------+
 | Windows 10                       | 3.7                       | 7.1.0            |x86-64        |
 +----------------------------------+---------------------------+------------------+--------------+
+| Windows 10/Cygwin 3.3            | 3.6, 3.7, 3.8, 3.9        | 8.4.0            |x86-64        |
++----------------------------------+---------------------------+------------------+--------------+
 | Windows 8.1 Pro                  | 2.6, 2.7, 3.2, 3.3, 3.4   | 2.4.0            |x86,x86-64    |
 +----------------------------------+---------------------------+------------------+--------------+
 | Windows 8 Pro                    | 2.6, 2.7, 3.2, 3.3, 3.4a3 | 2.2.0            |x86,x86-64    |