fix(tests): run sandbox integration on firecracker

tests/_docker.py

@@ -30,3 +30,16 @@ def docker_available() -> bool:
 
 def skip_unless_docker(reason: str = "docker unreachable"):
     return unittest.skipUnless(docker_available(), reason)
+
+
+def skip_unless_docker_or_firecracker(
+    reason: str = "neither Docker nor Firecracker selected",
+):
+    """Skip a backend-agnostic test unless one supported backend can run.
+
+    Firecracker does not require the host Docker daemon. The KVM coverage job
+    deliberately sets ``SKIP_DOCKER_TESTS`` to exclude Docker-only integration
+    classes while still exercising this path.
+    """
+    firecracker_selected = os.environ.get("BOT_BOTTLE_BACKEND") == "firecracker"
+    return unittest.skipUnless(firecracker_selected or docker_available(), reason)

tests/integration/test_sandbox_escape.py

@@ -31,7 +31,7 @@ from pathlib import Path
 from bot_bottle.backend import BottleSpec, get_bottle_backend
 from bot_bottle.bottle_state import cleanup_state
 from bot_bottle.manifest import ManifestIndex
-from tests._docker import skip_unless_docker
+from tests._docker import skip_unless_docker_or_firecracker
 
 
 # Secrets planted in the bottle env as literals (agents substitute via
@@ -67,7 +67,7 @@ _DUMMY_HOST_KEY = (
 )
 
 
-@skip_unless_docker()
+@skip_unless_docker_or_firecracker()
 @unittest.skipIf(
     os.environ.get("GITEA_ACTIONS") == "true"
     and os.environ.get("BOT_BOTTLE_BACKEND") != "firecracker",
@@ -91,11 +91,9 @@ class TestSandboxEscape(unittest.TestCase):
 
     @classmethod
     def setUpClass(cls) -> None:
-        # Docker is always required (the agent + companion containers run under it,
-        # and VM backends still use it for the gateway); the
-        # class-level @skip_unless_docker already covers that. Pin
-        # Docker when BOT_BOTTLE_BACKEND is unset to preserve the
-        # Docker-backed CI path.
+        # Pin Docker when BOT_BOTTLE_BACKEND is unset to preserve the
+        # Docker-backed CI path. Firecracker uses its persistent infra VM for
+        # the shared gateway and therefore does not require host Docker.
         cls._backend_name = os.environ.get("BOT_BOTTLE_BACKEND", "docker")
 
         # Throwaway static key for the git-gate fixture. It need not

tests/unit/test_docker_test_helpers.py

@@ -0,0 +1,35 @@
+"""Tests for integration-test backend selection helpers."""
+
+from __future__ import annotations
+
+import os
+import unittest
+from unittest.mock import patch
+
+from tests._docker import skip_unless_docker_or_firecracker
+
+
+class TestSkipUnlessDockerOrFirecracker(unittest.TestCase):
+    def test_firecracker_runs_when_docker_tests_are_disabled(self):
+        with patch.dict(
+            os.environ,
+            {"BOT_BOTTLE_BACKEND": "firecracker", "SKIP_DOCKER_TESTS": "1"},
+            clear=True,
+        ):
+            decorated = skip_unless_docker_or_firecracker()(type("Case", (), {}))
+
+        self.assertFalse(getattr(decorated, "__unittest_skip__", False))
+
+    def test_non_firecracker_still_skips_when_docker_tests_are_disabled(self):
+        with patch.dict(
+            os.environ,
+            {"BOT_BOTTLE_BACKEND": "docker", "SKIP_DOCKER_TESTS": "1"},
+            clear=True,
+        ):
+            decorated = skip_unless_docker_or_firecracker()(type("Case", (), {}))
+
+        self.assertTrue(decorated.__unittest_skip__)
+
+
+if __name__ == "__main__":
+    unittest.main()