matplotlib: use uv

- replace 'python -m pip' with 'uv pip'
- set cache to match uv usage
- use uv for CIBW_BUILD_FRONTEND
- set UV_EXTRA_INDEX_URL to our GitLab registry, with
  UV_INDEX_STRATEGY=unsafe-best-match and UV_ONLY_BINARY=:all: so we
  pick whichever source has a binary wheel
- drop 'allow-prereleases' from setup-uv since this only applies to the
  setup-python action

Signed-off-by: Trevor Gamblin <tgamblin@baylibre.com>

Author: threexc

.github/workflows/build-matplotlib.yml

@@ -10,6 +10,16 @@ on:
 
 permissions: {}
 
+env:
+  # Query PyPI + gitlab riscv64 mirror; pick best compatible wheel
+  # (`unsafe-best-match` = pip-like). `first-index` stops at PyPI for sdist
+  # packages like cffi, never consulting gitlab for the riscv64 wheel.
+  UV_EXTRA_INDEX_URL: https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple
+  UV_INDEX_STRATEGY: unsafe-best-match
+  # Refuse sdist for dependencies — wheels only. Forces uv to pick the gitlab
+  # riscv64 wheel instead of falling back to building cffi/cryptography/etc.
+  UV_ONLY_BINARY: ':all:'
+
 jobs:
   build_sdist:
     name: Build sdist
@@ -50,7 +60,7 @@ jobs:
           https://github.com/qhull/qhull/raw/2020.2/COPYING.txt
 
       - name: Install dependencies
-        run: python -m pip install build twine
+        run: uv pip install build twine
 
       - name: Build sdist
         id: sdist
@@ -96,7 +106,11 @@ jobs:
         env:
           CIBW_BUILD: "cp314-* cp314t-*"
           CIBW_ARCHS: "riscv64"
-          CIBW_ENVIRONMENT: 'PIP_PREFER_BINARY=1 PIP_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple'
+          CIBW_BUILD_FRONTEND: "build[uv]"
+          CIBW_ENVIRONMENT: >-
+            UV_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple
+            UV_INDEX_STRATEGY=unsafe-best-match
+            UV_ONLY_BINARY=:all:
 
       - name: Build wheels for CPython 3.13
         uses: pypa/cibuildwheel@8d2b08b68458a16aeb24b64e68a09ab1c8e82084  # v3.4.1
@@ -105,7 +119,11 @@ jobs:
         env:
           CIBW_BUILD: "cp313-*"
           CIBW_ARCHS: "riscv64"
-          CIBW_ENVIRONMENT: 'PIP_PREFER_BINARY=1 PIP_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple'
+          CIBW_BUILD_FRONTEND: "build[uv]"
+          CIBW_ENVIRONMENT: >-
+            UV_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple
+            UV_INDEX_STRATEGY=unsafe-best-match
+            UV_ONLY_BINARY=:all:
 
       - name: Build wheels for CPython 3.12
         uses: pypa/cibuildwheel@8d2b08b68458a16aeb24b64e68a09ab1c8e82084  # v3.4.1
@@ -114,7 +132,11 @@ jobs:
         env:
           CIBW_BUILD: "cp312-*"
           CIBW_ARCHS: "riscv64"
-          CIBW_ENVIRONMENT: 'PIP_PREFER_BINARY=1 PIP_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple'
+          CIBW_BUILD_FRONTEND: "build[uv]"
+          CIBW_ENVIRONMENT: >-
+            UV_EXTRA_INDEX_URL=https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple
+            UV_INDEX_STRATEGY=unsafe-best-match
+            UV_ONLY_BINARY=:all:
 
       - uses: actions/upload-artifact@043fb46d1a93c77aae656e7c1c64a875d1fc6a0a  # v7.0.1
         with:

.github/workflows/test-matplotlib.yml

@@ -17,6 +17,15 @@ env:
   NO_AT_BRIDGE: 1  # Necessary for GTK3 interactive test.
   OPENBLAS_NUM_THREADS: 1
   PYTHONFAULTHANDLER: 1
+  # Query PyPI + gitlab riscv64 mirror; pick best compatible wheel.
+  # `first-index` is wrong here — PyPI has cffi sdist so uv would never check
+  # gitlab for the riscv64 wheel. `unsafe-best-match` is pip-like and selects
+  # the riscv64 wheel from gitlab when PyPI lacks one.
+  UV_EXTRA_INDEX_URL: https://gitlab.com/api/v4/projects/riseproject%2Fpython%2Fwheel_builder/packages/pypi/simple
+  UV_INDEX_STRATEGY: unsafe-best-match
+  # Refuse sdist for dependencies — wheels only. Forces uv to pick the gitlab
+  # riscv64 wheel instead of falling back to building cffi/cryptography/etc.
+  UV_ONLY_BINARY: ':all:'
 
 jobs:
   test:
@@ -53,7 +62,6 @@ jobs:
         uses: astral-sh/setup-uv@fac544c07dec837d0ccb6301d7b5580bf5edae39 # v8.2.0
         with:
           python-version: ${{ matrix.python-version }}
-          allow-prereleases: true
           activate-environment: true
           enable-cache: false
 
@@ -103,15 +111,15 @@ jobs:
           sudo apt-get install -yy --no-install-recommends ffmpeg poppler-utils
           sudo apt-get install -yy --no-install-recommends libgirepository-2.0-dev
 
-      - name: Cache pip
+      - name: Cache uv
         uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae  # v5.0.5
         with:
-          path: ~/.cache/pip
+          path: ~/.cache/uv
           key: |
-            ${{ matrix.os }}-py${{ matrix.python-version }}-pip-${{
+            ${{ matrix.os }}-py${{ matrix.python-version }}-uv-${{
             hashFiles('upstream/pyproject.toml', 'upstream/ci/minver-requirements.txt') }}
           restore-keys: |
-            ${{ matrix.os }}-py${{ matrix.python-version }}-pip-
+            ${{ matrix.os }}-py${{ matrix.python-version }}-uv-
       - name: Cache ccache
         uses: actions/cache@27d5ce7f107fe9357f9df03efb73ab90386fccae  # v5.0.5
         with:
@@ -136,24 +144,24 @@ jobs:
         run: |
           # Upgrade pip and setuptools and wheel to get as clean an install as
           # possible.
-          python -m pip install --upgrade pip setuptools wheel
+          uv pip install --upgrade pip setuptools wheel
 
           # Install dependencies from PyPI.
           # Preinstall build requirements to enable no-build-isolation builds.
-          python -m pip install --upgrade --prefer-binary \
+          uv pip install --upgrade --prefer-binary \
             --group build --group test
 
           # Install optional dependencies from PyPI.
           # Sphinx is needed to run sphinxext tests
-          python -m pip install --upgrade sphinx!=6.1.2
+          uv pip install --upgrade sphinx!=6.1.2
 
           # GUI toolkits are pip-installable only for some versions of Python
           # so don't fail if we can't install them.  Make it easier to check
           # whether the install was successful by trying to import the toolkit
           # (sometimes, the install appears to be successful but shared
           # libraries cannot be loaded at runtime, so an actual import is a
           # better check).
-          python -m pip install --upgrade pycairo 'cairocffi>=0.8' 'PyGObject' &&
+          uv pip install --upgrade pycairo 'cairocffi>=0.8' 'PyGObject' &&
             (
               python -c 'import gi; gi.require_version("Gtk", "4.0"); from gi.repository import Gtk' &&
               echo 'PyGObject 4 is available' || echo 'PyGObject 4 is not available'
@@ -163,11 +171,11 @@ jobs:
             )
 
           # PyQt5 has no riscv64 wheels; skip.
-          python -mpip install --upgrade --only-binary :all: pyqt6 &&
+          uv pip install --upgrade --only-binary :all: pyqt6 &&
             python -c 'import PyQt6.QtCore' &&
             echo 'PyQt6 is available' ||
             echo 'PyQt6 is not available'
-          python -mpip install --upgrade --only-binary :all: pyside6 &&
+          uv pip install --upgrade --only-binary :all: pyside6 &&
             python -c 'import PySide6.QtCore' &&
             echo 'PySide6 is available' ||
             echo 'PySide6 is not available'
@@ -179,7 +187,7 @@ jobs:
 
           export CPPFLAGS='--coverage -fprofile-abs-path'
 
-          python -m pip install --no-deps --no-build-isolation --verbose \
+          uv pip install --no-deps --no-build-isolation --verbose \
             --config-settings=setup-args="-DrcParams-backend=Agg" \
             --editable .[dev]