Add CI tests in Pyodide

.github/workflows/ci.yml

@@ -3,6 +3,7 @@ on:
   push:
     branches:
       - main
+      - emscripten-ci2
   pull_request:
 
 concurrency:
@@ -350,3 +351,33 @@ jobs:
           CIBW_BUILD_VERBOSITY: 1
         with:
           package-dir: examples/namespace_package
+
+  emscripten:
+    name: emscripten
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v2
+      - uses: actions/setup-python@v2
+        id: setup-python
+        with:
+          python-version: "3.10"
+      - name: Install Rust toolchain
+        uses: actions-rs/toolchain@v1
+        with:
+          toolchain: stable
+          target: wasm32-unknown-emscripten
+      - uses: actions/setup-node@v3
+        with:
+          node-version: 18
+      - run: pip install nox
+      - uses: actions/cache@v3
+        id: cache
+        with:
+          path: |
+            emscripten/pyodide
+          key: ${{ hashFiles('emscripten/*') }} - ${{ hashFiles('noxfile.py') }} - ${{ steps.setup-python.outputs.python-path }}
+      - uses: Swatinem/rust-cache@v1
+        with:
+          key: cargo-emscripten-wasm32
+      - name: Test
+        run: nox -s test-emscripten

emscripten/.gitignore

@@ -0,0 +1,6 @@
+builddir
+main.*
+!main.c
+pybuilddir.txt
+pyodide
+node_modules

emscripten/_sysconfigdata__emscripten_wasm32-emscripten.py

@@ -0,0 +1,16 @@
+# system configuration generated and used by the sysconfig module
+build_time_vars = {
+    "ABIFLAGS": "",
+    "AR": "/src/emsdk/emsdk/upstream/emscripten/emar",
+    "ARFLAGS": "rcs",
+    "BLDSHARED": "emcc -sSIDE_MODULE=1",
+    "CC": "emcc -I../../emscripten",
+    "CCSHARED": "",
+    "CFLAGS": "-Wno-unused-result -Wsign-compare -Wunreachable-code -DNDEBUG -g "
+    "-fwrapv -O3 -Wall -O2 -g0 -fPIC",
+    "EXT_SUFFIX": ".cpython-310-wasm32-emscripten.so",
+    "HOST_GNU_TYPE": "wasm32-unknown-emscripten",
+    "LDSHARED": "emcc -sSIDE_MODULE=1",
+    "Py_DEBUG": "0",
+    "py_version_nodot": "310",
+}

emscripten/emcc_wrapper.py

@@ -0,0 +1,42 @@
+#!/usr/bin/env python3
+import subprocess
+import sys
+
+
+def update_args(args):
+    # https://github.com/emscripten-core/emscripten/issues/17109
+    args.insert(0, "-Wl,--no-whole-archive")
+
+    # Remove -s ASSERTIONS=1
+    # See https://github.com/rust-lang/rust/pull/97928
+    for i in range(len(args)):
+        if "ASSERTIONS" in args[i]:
+            del args[i - 1 : i + 1]
+            break
+
+    # remove -lc. Not sure if it makes a difference but -lc doesn't belong here.
+    # https://github.com/emscripten-core/emscripten/issues/17191
+    for i in reversed(range(len(args))):
+        if args[i] == "c" and args[i - 1] == "-l":
+            del args[i - 1 : i + 1]
+
+    # Prevent a bunch of errors caused by buggy behavior in
+    # `esmcripten/tools/building.py:lld_flags_for_executable` REQUIRED_EXPORTS
+    # contains symbols that should come from the main module.
+    # https://github.com/emscripten-core/emscripten/issues/17202
+    args.append("-sERROR_ON_UNDEFINED_SYMBOLS=0")
+    # Seems like --no-entry should be implied by SIDE_MODULE but apparently it
+    # isn't?
+    args.append("-Wl,--no-entry")
+
+    return args
+
+
+def main(args):
+    args = update_args(args)
+    return subprocess.call(["emcc"] + args)
+
+
+if __name__ == "__main__":
+    args = sys.argv[1:]
+    sys.exit(main(args))