Build Pyodide (WebAssembly) wheels

.github/workflows/pytests.yml

@@ -97,3 +97,20 @@ jobs:
     - name: Build wheel
       run: |
         python -m build --wheel
+
+  pyodide:
+    # WebAssembly (32-bit): cibuildwheel builds the wheels and runs the tests
+    # in Node.
+    name: Pyodide (WebAssembly)
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        submodules: recursive
+
+    - name: Build and test
+      uses: pypa/cibuildwheel@v4.3.5
+      env:
+        CIBW_PLATFORM: pyodide
+      with:
+        config-file: "{package}/pyproject-cibuildwheel.toml"

.github/workflows/wheels.yml

@@ -60,8 +60,28 @@ jobs:
           path: ./wheelhouse/*.whl
           if-no-files-found: error
 
+  build_pyodide:
+    name: Build Pyodide (WebAssembly) wheels
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v5
+        with:
+          submodules: true
+      - name: Build wheels
+        uses: pypa/cibuildwheel@v4.3.5
+        env:
+          CIBW_PLATFORM: pyodide
+        with:
+          config-file: "{package}/pyproject-cibuildwheel.toml"
+
+      - uses: actions/upload-artifact@v4
+        with:
+          name: wheel-artifact-pyodide
+          path: ./wheelhouse/*.whl
+          if-no-files-found: error
+
   upload_all:
-    needs: [build_wheels, sdist]
+    needs: [build_wheels, build_pyodide, sdist]
     name: Uploading built packages to pypi for release.
     runs-on: ubuntu-latest
     # Only upload to PyPI when triggered by a tag (not manual workflow_dispatch).

pyfusefilter/ffibuild.py

@@ -14,8 +14,14 @@
   all_src += src.read()
 
 
+# Under Pyodide (WebAssembly), a wheel is tied to one Pyodide version anyway,
+# so the limited API (abi3) gains nothing; and Pyodide 315 names abi3
+# extensions with quotes (_xorfilter.abi3-"wasm32-emscripten".so), which
+# Python then cannot import.
+import sysconfig
 ffi.set_source(
   "_xorfilter", all_src,
+  py_limited_api=not sysconfig.get_platform().startswith("emscripten"),
 )
 
 ffi.cdef(

pyproject-cibuildwheel.toml

@@ -13,5 +13,11 @@ archs = ["x86_64", "universal2", "arm64"]
 # The workflow runs on both x86_64 and aarch64 runners; build natively on each.
 archs = ["native"]
 
+[tool.cibuildwheel.pyodide]
+# WebAssembly wheels, one per Pyodide ABI (cp313: Pyodide 0.28 and 0.29;
+# cp314: Pyodide 314; cp315). In a Pyodide venv, the pytest script starts
+# with a shebang to a shell script, which macOS cannot run: python -m pytest.
+test-command = "python -m pytest {project}/tests -q --import-mode=importlib"
+
 [tool.cibuildwheel.windows]
 archs = ["AMD64"]

tests/test_fuse16.py

@@ -1,5 +1,5 @@
 from pyfusefilter import Fuse16
-from random import sample
+from random import randrange
 import tempfile, os
 
 
@@ -66,7 +66,10 @@ def test_fuse16_few_segments():
     # https://github.com/FastFilter/xor_singleheader/issues/77
     for size in (3551, 11504, 11521, 12372, 13224, 37454):
         for _ in range(5):
-            keys = sample(range(1 << 62), size)
+            keys = set()
+            while len(keys) < size:
+                keys.add(randrange(1 << 62))
+            keys = list(keys)
             filter = Fuse16(keys)
             for key in keys:
                 assert key in filter

tests/test_fuse8.py

@@ -1,5 +1,5 @@
 from pyfusefilter import Fuse8
-from random import sample
+from random import randrange
 import tempfile, os
 
 def test_readme():
@@ -65,7 +65,10 @@ def test_fuse8_few_segments():
     # https://github.com/FastFilter/xor_singleheader/issues/77
     for size in (3551, 11504, 11521, 12372, 13224, 37454):
         for _ in range(5):
-            keys = sample(range(1 << 62), size)
+            keys = set()
+            while len(keys) < size:
+                keys.add(randrange(1 << 62))
+            keys = list(keys)
             filter = Fuse8(keys)
             for key in keys:
                 assert key in filter