bitarray: add build-bitarray.yml for riscv64 wheels (#512)

bitarray is a plain setuptools project with two mandatory C extensions
(bitarray._bitarray, bitarray._util) and no vendored dependencies, so the
port is upstream's own cibuildwheel job narrowed to riscv64: the same
pypa/cibuildwheel invocation and the same test command, with the
manylinux_riscv64 image supplied because upstream carries no
[tool.cibuildwheel] table.

The test suite ships inside the wheel, so upstream's
`python -c "import bitarray; assert bitarray.test().wasSuccessful()"`
exercises the installed extension modules unchanged.

Co-authored-by: Claude Opus 5 <noreply@anthropic.com>

Author: luhenry

.github/workflows/build-bitarray.yml

@@ -0,0 +1,93 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on the `build_wheels` job of
+# https://github.com/ilanschnell/bitarray/blob/3.10.1/.github/workflows/build_wheels.yml
+name: Build bitarray wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'bitarray version to build (git tag, e.g. 3.10.1)'
+        required: true
+        default: '3.10.1'
+  pull_request:
+    paths:
+      - '.github/workflows/build-bitarray.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '3.10.1' }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+env:
+  BITARRAY_VERSION: ${{ inputs.version || '3.10.1' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  build_wheels:
+    name: Build bitarray ${{ inputs.version || '3.10.1' }} ${{ matrix.python }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    strategy:
+      fail-fast: false
+      matrix:
+        python:
+          - "cp312"
+          - "cp313"
+          - "cp314"
+          - "cp314t"
+
+    steps:
+      - name: Checkout bitarray ${{ env.BITARRAY_VERSION }}
+        uses: actions/checkout@9c091bb21b7c1c1d1991bb908d89e4e9dddfe3e0  # v7.0.0
+        with:
+          repository: ilanschnell/bitarray
+          ref: ${{ env.BITARRAY_VERSION }}
+          persist-credentials: false
+
+      - name: Build wheels
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        with:
+          output-dir: wheelhouse/
+          only: ${{ matrix.python }}-manylinux_riscv64
+        env:
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          CIBW_TEST_COMMAND: python -c "import bitarray; assert bitarray.test().wasSuccessful()"
+
+      - name: Check the C extensions made it into the wheel
+        run: |
+          python3 - wheelhouse/*.whl <<'EOF'
+          import sys, zipfile
+          for whl in sys.argv[1:]:
+              names = zipfile.ZipFile(whl).namelist()
+              for mod in ("_bitarray", "_util"):
+                  assert any(mod in n and n.endswith(".so") for n in names), (whl, mod)
+              print(whl, "ok")
+          EOF
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: bitarray-${{ env.BITARRAY_VERSION }}-${{ matrix.python }}-manylinux_riscv64
+          path: wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish bitarray ${{ inputs.version || '3.10.1' }} to GitLab
+    needs: [build_wheels]
+    runs-on: ubuntu-latest
+    permissions:
+      contents: write
+      pull-requests: write
+
+    steps:
+      - name: Publish wheels and open docs PR
+        uses: riseproject-dev/python-wheels/actions/publish-wheels@main
+        with:
+          artifact-pattern: bitarray-${{ env.BITARRAY_VERSION }}-*-manylinux_riscv64
+          gitlab-username: ${{ vars.GITLAB_DEPLOY_USER }}
+          gitlab-token: ${{ secrets.GITLAB_DEPLOY_TOKEN }}
+          gitlab-project-id: ${{ vars.GITLAB_PROJECT_ID }}
+          gh-token: ${{ secrets.GITHUB_TOKEN }}