Add Alpine to CI

.github/workflows/ci.yml

@@ -179,6 +179,31 @@ jobs:
           name: macOS (${{ matrix.python }})
           flags: macOS,${{ matrix.python }}
 
+  # run CI on a musl linux
+  Alpine:
+    name: "Alpine"
+    runs-on: ubuntu-latest
+    container: alpine
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v3
+      - name: Install necessary packages
+        # can't use setup-python because that python doesn't seem to work;
+        # `python3-dev` (rather than `python:alpine`) for some ctypes reason,
+        # `nodejs` for pyright (`node-env` pulls in nodejs but that takes a while and can time out the test).
+        run: apk update && apk add python3-dev bash nodejs
+      - name: Enter virtual environment
+        run: python -m venv .venv
+      - name: Run tests
+        run: source .venv/bin/activate && ./ci.sh
+      - if: always()
+        uses: codecov/codecov-action@v3
+        with:
+          directory: empty
+          token: 87cefb17-c44b-4f2f-8b30-1fff5769ce46
+          name: Alpine
+          flags: Alpine,3.12
+
   # https://github.com/marketplace/actions/alls-green#why
   check:  # This job does nothing and is only used for the branch protection
 
@@ -188,6 +213,7 @@ jobs:
       - Windows
       - Ubuntu
       - macOS
+      - Alpine
 
     runs-on: ubuntu-latest
 

src/trio/_tests/test_socket.py

@@ -624,8 +624,8 @@ async def res(
                 sock.setsockopt(tsocket.IPPROTO_IPV6, tsocket.IPV6_V6ONLY, True)
                 with pytest.raises(tsocket.gaierror) as excinfo:
                     await res(("1.2.3.4", 80))
-                # Windows, macOS
-                expected_errnos = {tsocket.EAI_NONAME}
+                # Windows, macOS, musl/Linux
+                expected_errnos = {tsocket.EAI_NONAME, tsocket.EAI_NODATA}
                 # Linux
                 if hasattr(tsocket, "EAI_ADDRFAMILY"):
                     expected_errnos.add(tsocket.EAI_ADDRFAMILY)