test(multiplayer): make local gate portable

scripts/test_verify_multiplayer_local.py

@@ -0,0 +1,19 @@
+from pathlib import Path
+import unittest
+
+
+ROOT = Path(__file__).parents[1]
+
+
+class LocalMultiplayerGateTest(unittest.TestCase):
+    def test_godot_gate_has_a_digest_pinned_container_fallback(self):
+        script = (ROOT / "scripts" / "verify_multiplayer_local.sh").read_text()
+        self.assertIn("run_godot_harness()", script)
+        self.assertIn("barichello/godot-ci@sha256:", script)
+        self.assertIn("docker run --rm --platform linux/amd64", script)
+        self.assertIn("type=bind,src=$root_dir,dst=/workspace", script)
+        self.assertIn("Godot executable not found", script)
+
+
+if __name__ == "__main__":
+    unittest.main()

scripts/verify_multiplayer_local.sh

@@ -3,11 +3,23 @@ set -euo pipefail
 
 root_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 godot_bin="${GODOT_BIN:-/Applications/Godot.app/Contents/MacOS/Godot}"
+godot_image="barichello/godot-ci@sha256:622e5ca81b54cd8038ecf7de5d157b47efc800d7cf635af2eec18a6aee4bab7e"
 
-if [[ ! -x "$godot_bin" ]]; then
-  echo "local multiplayer gate: Godot executable not found: $godot_bin" >&2
-  exit 2
-fi
+run_godot_harness() {
+  if [[ -x "$godot_bin" ]]; then
+    "$godot_bin" --headless --path "$root_dir/Game" res://tests/test_runner.tscn
+    return
+  fi
+  if ! command -v docker >/dev/null 2>&1 || ! docker info >/dev/null 2>&1; then
+    echo "local multiplayer gate: Godot executable not found ($godot_bin), and Docker is unavailable for the pinned headless fallback" >&2
+    return 2
+  fi
+  echo "local multiplayer gate: using pinned headless Godot container fallback"
+  docker run --rm --platform linux/amd64 \
+    --mount "type=bind,src=$root_dir,dst=/workspace" \
+    -w /workspace "$godot_image" \
+    godot --headless --path Game res://tests/test_runner.tscn
+}
 
 echo "local multiplayer gate: Go tests"
 (cd "$root_dir/server" && go test ./...)
@@ -22,7 +34,7 @@ echo "local multiplayer gate: bounded fuzz targets"
 (cd "$root_dir/server" && go test ./domain -fuzz FuzzSyncEventApplicationDoesNotPanic -fuzztime=2s)
 
 echo "local multiplayer gate: Godot harness"
-"$godot_bin" --headless --path "$root_dir/Game" res://tests/test_runner.tscn
+run_godot_harness
 
 echo "local multiplayer gate: contracts and manifests"
 python3 -m json.tool "$root_dir/server/contracts/v1/openapi.json" >/dev/null