Add a minimal pyproject.toml (celiagg#114)

This is enough to permit installation without needing numpy and cython in the environment via PEP-517 style isolated builds. Text rendering in the builds is now controlled by an environment variable. Fixes celiagg#105
suarezvictor · Apr 14, 2023 · 5e298c8 · 5e298c8
1 parent e5bc04a
commit 5e298c8
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Showing 4 changed files with 49 additions and 34 deletions.
diff --git a/.github/workflows/test-pr.yml b/.github/workflows/test-pr.yml
@@ -24,13 +24,13 @@ jobs:
       uses: actions/setup-python@v4
       with:
         python-version: ${{ matrix.python-version }}
-    - name: Install dependencies
-      run: python -m pip install cython numpy
-    - name: Install library (w/ text rendering support)
+    - name: Install library and dependencies
       run: python -m pip install -e .
       if: matrix.os == 'ubuntu-latest'
-    - name: Install library (w/o text rendering support)
-      run: python -m pip install -e . --install-option --no-text-rendering
+    - name: Install library and dependencies (no text rendering)
+      run: python -m pip install -e .
+      env:
+        CELIAGG_NO_TEXT_RENDERING: 1
       if: matrix.os != 'ubuntu-latest'
     - name: Run tests
       run: python -m unittest discover -v celiagg
diff --git a/README.rst b/README.rst
@@ -26,6 +26,11 @@ Building from source with the Freetype font library on macOS requires
 the `pkg-config` tool which can be installed via Homebrew, MacPorts, or
 other macOS package management systems.
 
+To build without text support, set the ``CELIAGG_NO_TEXT_RENDERING``
+environment variable while building, eg.
+``CELIAGG_NO_TEXT_RENDERING=1 pip install celiagg``
+
+
 Dependencies
 ------------
 

diff --git a/pyproject.toml b/pyproject.toml
@@ -0,0 +1,3 @@
+[build-system]
+requires = ["cython", "oldest-supported-numpy", "setuptools", "wheel"]
+build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
@@ -40,18 +40,6 @@
     print("Cython does not appear to be installed.  Will attempt to use "
           "pre-made cpp file...")
 
-# Disable text rendering with this option
-if '--no-text-rendering' in sys.argv:
-    del sys.argv[sys.argv.index('--no-text-rendering')]
-    with_text_rendering = False
-else:
-    with_text_rendering = True
-    with_pkgconfig = True
-    # Disable pkg-config use with this option
-    if '--no-pkg-config' in sys.argv:
-        del sys.argv[sys.argv.index('--no-pkg-config')]
-        with_pkgconfig = False
-
 
 class PatchedSdist(_sdist):
     """ Make sure the compiled Cython files are included
@@ -63,6 +51,30 @@ def run(self):
         _sdist.run(self)
 
 
+def has_text_rendering():
+    return not os.environ.get("CELIAGG_NO_TEXT_RENDERING", None)
+
+
+def has_pkgconfig():
+    try:
+        subprocess.run(
+            ['pkg-config', '--version'],
+            check=True,
+            capture_output=True,
+        )
+        return True
+    except subprocess.CalledProcessError:
+        print(
+            "Failed to execute pkg-config.  Either disable building with "
+            "text rendering using CELIAGG_NO_TEXT_RENDERING environment "
+            "variable; install pkg-config; or supply appropriate "
+            "CFLAGS and LDFLAGS environment variables for FreeType2 and "
+            "Harfbuzz.\n\n",
+            file=sys.stderr,
+        )
+        return False
+
+
 def run_pkgconfig(name, exit_on_fail=True):
     """ Use pkg-config to locate a library installed on the system.
 
@@ -96,19 +108,15 @@ def collect_data(env=None):
 
     if len(data) < 2:
         msg = ("Failed to execute pkg-config {name}. If {name} is "
-               "installed in standard system locations, it may work to run "
-               "this script with --no-pkg-config. Otherwise, appropriate "
-               "CFLAGS and LDFLAGS environment variables must be set.\n\n"
+               "installed in standard system locations, this may still work. "
+               "Otherwise, appropriate CFLAGS and LDFLAGS environment "
+               "variables must be set.\n\n"
                "If you wish to disable text rendering, you can re-run this "
                "script with the --no-text-rendering flag.")
         print(msg.format(name=name), file=sys.stderr)
 
-        # NOTE: Avoid exiting when pip is running an egg_info command. Without
-        # this, it's not possible to avoid freetype when installing from pip.
-        if exit_on_fail and 'egg_info' not in sys.argv:
-            exit(-1)
-        else:
-            return [], []
+        # couldn't find flags, so return empty lists
+        return [], []
     return data['cflags'], data['ldflags']
 
 
@@ -168,15 +176,16 @@ def create_extension():
         ('NPY_NO_DEPRECATED_API', 'NPY_1_7_API_VERSION'),
     ]
 
-    if with_text_rendering:
+    if has_text_rendering():
+        print("Text rendering enabled.", file=sys.stderr)
         if platform.system() == 'Windows':
             extra_link_args.extend(['Gdi32.lib', 'User32.lib'])
             include_dirs.append('agg-svn/agg-2.4/font_win32_tt')
             font_source = 'agg-svn/agg-2.4/font_win32_tt/agg_font_win32_tt.cpp'
 
             # XXX: Figure out how to enable Harfbuzz!
         else:
-            if with_pkgconfig:
+            if has_pkgconfig():
                 cflags, ldflags = run_pkgconfig('freetype2')
                 extra_compile_args.extend(cflags)
                 extra_link_args.extend(ldflags)
@@ -191,8 +200,11 @@ def create_extension():
             define_macros.append(('_USE_FREETYPE', None))
             include_dirs.append('agg-svn/agg-2.4/font_freetype')
             font_source = 'agg-svn/agg-2.4/font_freetype/agg_font_freetype.cpp'
+
         sources.append(font_source)
         define_macros.append(('_ENABLE_TEXT_RENDERING', None))
+    else:
+        print("Text rendering disabled.", file=sys.stderr)
 
     return Extension(
         'celiagg._celiagg',
@@ -208,11 +220,6 @@ def create_extension():
 with open('README.rst', 'r') as fp:
     long_description = fp.read()
 
-requires = ['numpy']
-if sys.platform not in ('win32', 'cygwin'):
-    # Windows doesn't use FreeType.
-    requires.append('freetype')
-
 cmdclass = {'sdist': PatchedSdist}
 if cython_build_ext is not None:
     cmdclass['build_ext'] = cython_build_ext
@@ -240,7 +247,7 @@ def create_extension():
         'Operating System :: Unix',
         'Operating System :: MacOS',
     ],
-    requires=requires,
+    install_requires=['numpy'],
     cmdclass=cmdclass,
     ext_modules=[create_extension()],
     packages=['celiagg', 'celiagg.tests'],