ci: add GitHub Actions workflow for building binaries on macOS

.github/workflows/build-binary.yml

@@ -0,0 +1,119 @@
+name: Build binaries
+
+on:
+  push:
+    paths:
+      - '**.py'
+      - '**.pyx'
+      - '**.c'
+      - '**.h'
+      - '**.yml'
+      - '**.toml'
+      - '**.cfg'
+      - '**.ini'
+      - 'requirements.d/*'
+      - 'scripts/**'
+  pull_request:
+    paths:
+      - '**.py'
+      - '**.pyx'
+      - '**.c'
+      - '**.h'
+      - '**.yml'
+      - '**.toml'
+      - '**.cfg'
+      - '**.ini'
+      - 'requirements.d/*'
+      - 'scripts/**'
+  workflow_dispatch:
+
+jobs:
+  build-binary-macos:
+    name: Build (macOS ${{ matrix.os }} / ${{ runner.arch }})
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [macos-12, macos-14]
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 60
+
+    env:
+      # Support both Homebrew locations (Intel and Apple Silicon)
+      PKG_CONFIG_PATH: "/opt/homebrew/opt/openssl@3.0/lib/pkgconfig:/usr/local/opt/openssl@3.0/lib/pkgconfig:$PKG_CONFIG_PATH"
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+        with:
+            # Just fetching one commit is not enough for setuptools-scm, so we fetch all
+            fetch-depth: 0
+
+      - name: Set up Python 3.11
+        uses: actions/setup-python@v5
+        with:
+          python-version: '3.11'
+
+      - name: Cache pip
+        uses: actions/cache@v4
+        with:
+          path: ~/.cache/pip
+          key: ${{ runner.os }}-pip-${{ hashFiles('requirements.d/development.txt') }}
+          restore-keys: |
+            ${{ runner.os }}-pip-
+            ${{ runner.os }}-
+
+      - name: Install macOS packages via Homebrew (see Brewfile)
+        run: |
+          brew bundle install
+
+      - name: Install Python requirements
+        run: |
+          python -m pip install --upgrade pip setuptools wheel
+          pip install -r requirements.d/development.txt
+
+      - name: Build Borg to compile extensions
+        env:
+          # Set both paths again to be sure nothing overrides them
+          PKG_CONFIG_PATH: "/opt/homebrew/opt/openssl@3.0/lib/pkgconfig:/usr/local/opt/openssl@3.0/lib/pkgconfig:${{ env.PKG_CONFIG_PATH }}"
+        run: |
+          pip install -ve .
+
+      - name: Build PyInstaller single-file binary
+        run: |
+          python -m pip install 'pyinstaller==6.7.0'
+          mkdir -p dist/binary
+          pyinstaller --clean --distpath=dist/binary scripts/borg.exe.spec
+          pushd dist/binary
+          tar -czvf borg.tgz borg-dir
+          rm -rf borg-dir
+          popd
+
+      - name: Smoke-test the built binary (borg -V)
+        run: |
+          pushd dist/binary
+          ls -l
+          # test single-file binary
+          chmod +x borg.exe
+          ./borg.exe -V
+          # test single-dir binary
+          tar -xzvf borg.tgz
+          chmod +x borg-dir/borg.exe
+          ./borg-dir/borg.exe -V
+          popd
+
+      - name: Prepare artifacts
+        run: |
+          mkdir -p artifacts
+          if [ -f dist/binary/borg.exe ]; then
+            cp dist/binary/borg.exe artifacts/borg-${{ matrix.os }}-${{ runner.arch }}
+          fi
+          if [ -f dist/binary/borg.tgz ]; then
+            cp dist/binary/borg.tgz artifacts/borg-dir-${{ matrix.os }}-${{ runner.arch }}.tgz
+          fi
+
+      - name: Upload artifacts
+        uses: actions/upload-artifact@v4
+        with:
+          name: borg-macos-${{ matrix.os }}-${{ runner.arch }}
+          path: artifacts/*
+          if-no-files-found: error