boost-histogram: add build-boost-histogram.yml for riscv64 wheels

.github/workflows/build-boost-histogram.yml

@@ -0,0 +1,151 @@
+# SPDX-FileCopyrightText: 2026 The RISE Project
+# SPDX-License-Identifier: MIT
+---
+# This workflow is based on upstream's own wheel build setup:
+#   https://github.com/scikit-hep/boost-histogram/blob/v1.8.1/.github/workflows/wheels.yml
+name: Build boost-histogram wheels (riscv64)
+
+on:
+  workflow_dispatch:
+    inputs:
+      version:
+        description: 'boost-histogram version to build (git tag without leading v, e.g. 1.8.1)'
+        required: true
+        default: '1.8.1'
+  pull_request:
+    paths:
+      - '.github/workflows/build-boost-histogram.yml'
+
+concurrency:
+  group: ${{ github.workflow }}-${{ inputs.version || '1.8.1' }}-${{ github.head_ref || github.run_id }}
+  cancel-in-progress: true
+
+permissions:
+  contents: read  # to fetch code (actions/checkout)
+
+env:
+  # `inputs.version` is empty on pull_request events; default to 1.8.1 there.
+  BOOST_HISTOGRAM_VERSION: ${{ inputs.version || '1.8.1' }}
+  MANYLINUX_RISCV64_IMAGE: quay.io/pypa/manylinux_2_39_riscv64
+
+jobs:
+  setup:
+    uses: $/.github/workflows/_setup.yml
+
+  build_sdist:
+    needs: [setup]
+    # The sdist packages the source tree plus the vendored Boost.Histogram/Core/Mp11/
+    # Config/ThrowException/Assert/Variant2 headers (git submodules) and a
+    # setuptools-scm-derived version. It's architecture-independent, so build it once
+    # on x86 instead of burning a scarce riscv runner (CLAUDE.md gotcha 4).
+    name: Build boost-histogram ${{ inputs.version || '1.8.1' }} sdist
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+    outputs:
+      sdist_name: ${{ steps.sdist.outputs.sdist_name }}
+      package_version: ${{ steps.sdist.outputs.package_version }}
+    steps:
+      - name: Checkout boost-histogram v${{ env.BOOST_HISTOGRAM_VERSION }}
+        uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1  # v7.0.1
+        with:
+          repository: scikit-hep/boost-histogram
+          ref: v${{ env.BOOST_HISTOGRAM_VERSION }}
+          submodules: recursive
+          fetch-depth: 0
+          fetch-tags: true
+          persist-credentials: false
+
+      - name: Install Python
+        uses: astral-sh/setup-uv@20cfd1bf945f4377ade1205e4dbc17946fc9a30d  # v10.0.1
+        with:
+          python-version: '3.12'
+          activate-environment: true
+          enable-cache: false
+
+      - name: Build sdist
+        id: sdist
+        run: |
+          uv pip install build twine
+          python -m build --sdist
+          twine check --strict dist/*.tar.gz
+          sdists=(dist/*.tar.gz)
+          echo "sdist_name=$(basename "${sdists[0]}")" >> "$GITHUB_OUTPUT"
+          echo "package_version=$(basename "${sdists[0]}" | sed -En 's/boost_histogram-(.+)\.tar\.gz/\1/p')" >> "$GITHUB_OUTPUT"
+
+      - name: Upload sdist artifact
+        uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: boost-histogram-${{ env.BOOST_HISTOGRAM_VERSION }}-sdist
+          path: dist/*.tar.gz
+          if-no-files-found: error
+
+  build_wheels:
+    needs: [setup, build_sdist]
+    name: Build boost-histogram ${{ inputs.version || '1.8.1' }} ${{ matrix.python }}-manylinux_riscv64
+    runs-on: ubuntu-24.04-riscv
+    permissions:
+      contents: read
+    strategy:
+      fail-fast: false
+      matrix:
+        python: ["cp312", "cp313", "cp314", "cp314t"]
+        include:
+          # hypothesis (a test dependency) ships no riscv64 wheel for PyPI's
+          # newest release on the free-threaded ABI; our own registry's older
+          # build does. Widening UV_ONLY_BINARY doesn't help - uv's resolver
+          # still picks the newest version first and tries to build its sdist
+          # (which needs a Rust toolchain riscv64 lacks) rather than falling
+          # back to a version with a usable wheel, so pin the version instead.
+          - python: "cp314t"
+            test_requires: "hypothesis==6.165.10"
+
+    steps:
+      - name: Download sdist
+        uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c  # v8.0.1
+        with:
+          name: boost-histogram-${{ env.BOOST_HISTOGRAM_VERSION }}-sdist
+          path: dist/
+
+      - name: Build wheels
+        uses: pypa/cibuildwheel@1828c10ab37f080699c7b81cea34097c684a7074  # v4.2.0
+        with:
+          package-dir: dist/${{ needs.build_sdist.outputs.sdist_name }}
+        env:
+          CIBW_BUILD: ${{ matrix.python }}-*
+          CIBW_ARCHS: riscv64
+          # numpy (a hard runtime dependency) ships no musllinux riscv64 wheel
+          # anywhere, so musllinux is dropped (workflow-anatomy.md: an accepted
+          # outcome).
+          CIBW_SKIP: '*-musllinux_*'
+          CIBW_MANYLINUX_RISCV64_IMAGE: ${{ env.MANYLINUX_RISCV64_IMAGE }}
+          # CIBW_ENVIRONMENT replaces, rather than merges into, upstream's own
+          # [tool.cibuildwheel] environment table (CLAUDE.md gotcha 107), so its
+          # four keys are repeated here alongside our registry. The test-install
+          # step resolves with uv, which only reads UV_* names, not PIP_* (CLAUDE.md
+          # gotcha 244), so both are set.
+          CIBW_ENVIRONMENT: >-
+            PIP_ONLY_BINARY=numpy
+            PIP_PREFER_BINARY=1
+            UV_ONLY_BINARY=numpy
+            UV_PREFER_BINARY=1
+            PIP_EXTRA_INDEX_URL=https://pypi.riseproject.dev/simple/
+            UV_EXTRA_INDEX_URL=https://pypi.riseproject.dev/simple/
+            UV_INDEX_STRATEGY=unsafe-best-match
+          CIBW_TEST_REQUIRES: ${{ matrix.test_requires }}
+
+      - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
+        with:
+          name: boost-histogram-${{ env.BOOST_HISTOGRAM_VERSION }}-${{ matrix.python }}-manylinux_riscv64
+          path: ./wheelhouse/*.whl
+          if-no-files-found: error
+
+  publish:
+    name: Publish boost-histogram ${{ inputs.version || '1.8.1' }}
+    needs: [setup, build_wheels]
+    permissions:
+      contents: write
+      pull-requests: write
+    uses: $/.github/workflows/_publish-wheel.yml
+    with:
+      artifact-pattern: boost-histogram-${{ inputs.version || '1.8.1' }}-*-manylinux_riscv64