maint: add CI check to build against Ubuntu Flint deb

.github/workflows/buildwheel.yml

@@ -120,36 +120,38 @@ jobs:
       - run: pip install --no-index --find-links wheelhouse python_flint
       - run: python -m flint.test --verbose
 
-  test_pip_vcs_sdist:
-    name: pip install ${{ matrix.target }} on ${{ matrix.python-version }}
-    runs-on: ubuntu-22.04
+  # On new enough Ubuntu we can build against the system deb.
+  test_pip_flint_deb:
+    name: Build on ${{ matrix.os }}
+    runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        python-version: ['3.11', '3.12', '3.13-dev']
-        # '.' means install from python-flint git checkout
-        # 'python-flint' means install from PyPI sdist
-        target: ['.', 'python-flint']
+        os: [ubuntu-24.04]
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: ${{ matrix.python-version }}
-      - run: bin/pip_install_ubuntu.sh ${{ matrix.target }}
+          python-version: '3.12'
+      - run: sudo apt-get update
+      - run: sudo apt-get install libflint-dev
+      - run: pip install .
       - run: python -m flint.test --verbose
 
+  # For older Ubuntu we have to build Flint >= 3.0.0
   test_flint_versions:
-    name: Test flint ${{ matrix.flinttag }}
+    name: Test flint ${{ matrix.flint-tag }}
     runs-on: ubuntu-22.04
     strategy:
       fail-fast: false
       matrix:
         # Supported versions and latest git
-        flinttag: ['v3.0.0', 'v3.0.1', 'v3.1.0', 'main']
+        flint-tag: ['v3.0.0', 'v3.0.1', 'v3.1.0', 'v3.1.1', 'v3.1.2', 'main']
     steps:
       - uses: actions/checkout@v4
       - uses: actions/setup-python@v5
         with:
-          python-version: 3.12
-      - run: bin/pip_install_ubuntu.sh . ${{ matrix.flinttag }}
+          python-version: '3.12'
+      - run: bin/install_flint_ubuntu.sh ${{ matrix.flint-tag }}
+      - run: pip install .
       - run: python -m flint.test --verbose

README.md

@@ -40,10 +40,20 @@ First install FLINT 3. Starting with python-flint 0.5.0 older versions of Flint
 such as 2.9 are not supported any more. Note that as of Flint 3 Arb no longer
 needs to be built separately as it is now merged into Flint.
 
-See here for instructions on building FLINT:
+As of e.g. Ubuntu 24.04 a new enough version of FLINT (at least version 3) can
+be installed from the Ubuntu repos like
+
+    sudo apt-get install libflint-dev
+
+For older distros the version in the repos is too old and a newer version of
+FLINT needs to be built. See here for instructions on building FLINT:
 
 * http://flintlib.org/
 
+A script that builds and installs FLINT on Ubuntu can be found here:
+
+* https://github.com/flintlib/python-flint/blob/master/bin/install_flint_ubuntu.sh
+
 The latest release of Python-FLINT can then be built from source and installed
 using:
 
@@ -54,11 +64,6 @@ as follows:
 
     pip install .
 
-A script that builds and installs FLINT and python-flint that is tested on
-Ubuntu can be found in the git repo here:
-
-* https://github.com/flintlib/python-flint/blob/master/bin/pip_install_ubuntu.sh
-
 See the documentation for further notes on building and installing
 python-flint:
 

bin/install_flint_ubuntu.sh

@@ -0,0 +1,52 @@
+#!/bin/bash
+
+set -o errexit
+
+#
+# This script should work to build and install Flint from git on Ubuntu
+#
+#  $ git clone https://github.com/flintlib/python-flint.git
+#  $ cd python-flint
+#  $ bin/install_flint_ubuntu.sh v3.1.0
+#
+# The version is a tag or branch in the Flint repository.
+#
+# Then to install an sdist from PyPI, use
+#
+#  $ pip install python-flint
+#
+# To install python-flint from the git checkout
+#
+#  $ pip install .
+#
+
+echo "Building from git: $1"
+GIT_REF=$1
+
+# Install runtime and build dependencies
+
+# First install their dependencies and build dependencies
+sudo apt-get update
+sudo apt-get install libgmp-dev libmpfr-dev xz-utils ninja-build
+
+#
+# This will default to installing in /usr/local. If you want to install in a
+# non-standard location then configure flint with
+#    ./configure --disable-static --prefix=$PREFIX
+# If $PREFIX is not in default search paths, then at build time set
+#    export C_INCLUDE_PATH=$PREFIX/include
+# and at runtime set
+#    export LD_LIBRARY_PATH=$PREFIX/lib
+#
+echo "Installing Flint from git: $GIT_REF"
+git clone https://github.com/flintlib/flint.git
+cd flint
+  git checkout $GIT_REF
+  ./bootstrap.sh
+  ./configure --disable-static
+  make -j
+  sudo make install
+cd ..
+
+ls -l /usr/local/lib
+sudo ldconfig /usr/local/lib