build: add --local-flint to set rpath in dev build

.gitignore

@@ -1,4 +1,5 @@
 build/*
+build-install/*
 dist/*
 src/flint/**/*.c
 src/flint/*.html

.spin/cmds.py

@@ -0,0 +1,53 @@
+import os.path
+import click
+from spin.cmds import meson
+
+#
+# Wrap spin's build command to add the --local-flint argument
+#
+
+@click.command()
+@click.argument("meson_args", nargs=-1)
+@click.option("-j", "--jobs", help="Number of parallel tasks to launch", type=int)
+@click.option("--clean", is_flag=True, help="Clean build directory before build")
+@click.option(
+    "-v", "--verbose", is_flag=True, help="Print all build output, even installation"
+)
+
+@click.option("--local-flint",
+    help="Path to pkgconfig directory for a local build of flint and other directories")
+
+@click.pass_context
+def build(ctx, *args, local_flint=None, **kwargs):
+    """🔧 Build package with Meson/ninja and install
+
+    To link against a local build of flint use e.g.
+
+      spin build --local-flint=.local/lib/pkgconfig
+
+    MESON_ARGS are passed through e.g.:
+
+      spin build -- -Dpkg_config_path=/lib64/pkgconfig
+
+    The package is installed to build-install
+
+    By default meson-python does release builds. To be able to use a debugger,
+    tell meson to build in debug mode:
+
+      spin build -- -Dbuildtype=debug
+
+    or set CFLAGS appropriately:
+
+      CFLAGS="-O0 -g" spin build
+    """
+    if local_flint is not None:
+        pkg_config_path = os.path.abspath(local_flint)
+        ctx.params["meson_args"] += (
+            f'-Dpkg_config_path={pkg_config_path}',
+            f'-Dadd_flint_rpath=true',
+        )
+
+    del ctx.params["local_flint"]
+
+    # Call spin's build function
+    ctx.forward(meson.build)

meson.build

@@ -9,6 +9,16 @@ gmp_dep = dependency('gmp')
 mpfr_dep = dependency('mpfr')
 flint_dep = dependency('flint')
 
+# Add rpaths for a local build of flint found via pkgconfig
+#   https://github.com/mesonbuild/meson/issues/13046
+if get_option('add_flint_rpath')
+  flint_lib_dir = flint_dep.get_pkgconfig_variable('libdir')
+  add_project_link_arguments(
+    '-Wl,-rpath=' + flint_lib_dir,
+    language: 'c',
+  )
+endif
+
 # flint.pc was missing -lflint until Flint 3.1.0
 if flint_dep.version().version_compare('<3.1')
   flint_dep = cc.find_library('flint')

meson.options

@@ -0,0 +1 @@
+option('add_flint_rpath', type : 'boolean', value : false)

pyproject.toml

@@ -25,7 +25,7 @@ package = "flint"
 [tool.spin.commands]
 
 "Build" = [
-    "spin.cmds.meson.build",
+    ".spin/cmds.py:build",
     "spin.cmds.meson.test",
     "spin.cmds.build.sdist",
     "spin.cmds.pip.install",

requirements-dev.txt

@@ -0,0 +1,7 @@
+cython
+spin
+meson
+meson-python
+pytest
+coverage
+pytest-cov