Add building of pyodide universal wheels (#918)

.github/workflows/pypi.yml

@@ -57,6 +57,31 @@ jobs:
           name: wheels-${{ matrix.platform }}
           path: ./wheelhouse/*.whl
 
+  build_universal_wheel:
+    name: Build universal wheel for Pyodide
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Set up Python
+        uses: actions/setup-python@v4
+        with:
+          python-version: '3.11'
+
+      - name: Install dependencies
+        run: pip install numpy versioneer wheel
+
+      - name: Build universal wheel
+        run: |
+          PYODIDE=1 python setup.py bdist_wheel --universal
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: universal_wheel
+          path: dist/*.whl
+
   check_dist:
     name: Check dist
     needs: [make_sdist,build_wheels]
@@ -103,6 +128,11 @@ jobs:
           path: dist
           merge-multiple: true
 
+      - uses: actions/download-artifact@v4
+        with:
+          name: universal_wheel
+          path: dist
+
       - uses: pypa/gh-action-pypi-publish@v1.9.0
         with:
           user: __token__

setup.py

 #!/usr/bin/env python
+import os
+
 import numpy
 import versioneer
 from setuptools import Extension, setup
@@ -11,17 +13,26 @@ dist.parse_config_files()
 
 NAME: str = dist.get_name()  # type: ignore
 
+# Check if building for Pyodide
+is_pyodide = os.getenv("PYODIDE", "0") == "1"
+
+if is_pyodide:
+    # For pyodide we build a universal wheel that must be pure-python
+    # so we must omit the cython-version of scan.
+    ext_modules = []
+else:
+    ext_modules = [
+        Extension(
+            name="pytensor.scan.scan_perform",
+            sources=["pytensor/scan/scan_perform.pyx"],
+            include_dirs=[numpy.get_include()],
+        ),
+    ]
 
 if __name__ == "__main__":
     setup(
         name=NAME,
         version=versioneer.get_version(),
         cmdclass=versioneer.get_cmdclass(),
-        ext_modules=[
-            Extension(
-                name="pytensor.scan.scan_perform",
-                sources=["pytensor/scan/scan_perform.pyx"],
-                include_dirs=[numpy.get_include()],
-            ),
-        ],
+        ext_modules=ext_modules,
     )