fix resource leaks in qmp tests

pkgs/clan-cli/tests/test_vms_cli.py

@@ -83,15 +83,15 @@ def test_vm_qmp(
     vm = run_vm_in_thread("my_machine")
 
     # connect with qmp
-    qmp = qmp_connect("my_machine", vm)
+    with qmp_connect("my_machine", vm) as qmp:
+        # verify that issuing a command works
+        # result = qmp.cmd_obj({"execute": "query-status"})
+        result = qmp.command("query-status")
+        assert result["status"] == "running", result
 
-    # verify that issuing a command works
-    # result = qmp.cmd_obj({"execute": "query-status"})
-    result = qmp.command("query-status")
-    assert result["status"] == "running", result
-
-    # shutdown machine (prevent zombie qemu processes)
-    qmp.command("system_powerdown")
+        # shutdown machine (prevent zombie qemu processes)
+        qmp.command("system_powerdown")
+    vm.join()
 
 
 @pytest.mark.skipif(no_kvm, reason="Requires KVM")
@@ -130,48 +130,49 @@ def test_vm_persistence(
     vm = run_vm_in_thread("my_machine")
 
     # wait for the VM to start and connect qga
-    qga = qga_connect("my_machine", vm)
+    with qga_connect("my_machine", vm) as qga:
+        # create state via qmp command instead of systemd service
+        qga.run("echo 'dream2nix' > /var/my-state/root", check=True)
+        qga.run("echo 'dream2nix' > /var/my-state/test", check=True)
+        qga.run("chown test /var/my-state/test", check=True)
+        qga.run("chown test /var/user-state", check=True)
+        qga.run("touch /var/my-state/rebooting", check=True)
+        qga.exec_cmd("poweroff")
 
-    # create state via qmp command instead of systemd service
-    qga.run("echo 'dream2nix' > /var/my-state/root", check=True)
-    qga.run("echo 'dream2nix' > /var/my-state/test", check=True)
-    qga.run("chown test /var/my-state/test", check=True)
-    qga.run("chown test /var/user-state", check=True)
-    qga.run("touch /var/my-state/rebooting", check=True)
-    qga.exec_cmd("poweroff")
+        # wait for socket to be down (systemd service 'poweroff' rebooting machine)
+        wait_vm_down("my_machine", vm)
 
-    # wait for socket to be down (systemd service 'poweroff' rebooting machine)
-    wait_vm_down("my_machine", vm)
+    vm.join()
 
-    # start vm again
+    ## start vm again
     vm = run_vm_in_thread("my_machine")
 
-    # connect second time
-    qga = qga_connect("my_machine", vm)
-    # check state exists
-    qga.run("cat /var/my-state/test", check=True)
-    # ensure root file is owned by root
-    qga.run("stat -c '%U' /var/my-state/root", check=True)
-    # ensure test file is owned by test
-    qga.run("stat -c '%U' /var/my-state/test", check=True)
-    # ensure /var/user-state is owned by test
-    qga.run("stat -c '%U' /var/user-state", check=True)
+    ## connect second time
+    with qga_connect("my_machine", vm) as qga:
+        # check state exists
+        qga.run("cat /var/my-state/test", check=True)
+        # ensure root file is owned by root
+        qga.run("stat -c '%U' /var/my-state/root", check=True)
+        # ensure test file is owned by test
+        qga.run("stat -c '%U' /var/my-state/test", check=True)
+        # ensure /var/user-state is owned by test
+        qga.run("stat -c '%U' /var/user-state", check=True)
 
-    # ensure that the file created by the service is still there and has the expected content
-    exitcode, out, err = qga.run("cat /var/my-state/test")
-    assert exitcode == 0, err
-    assert out == "dream2nix\n", out
+        # ensure that the file created by the service is still there and has the expected content
+        exitcode, out, err = qga.run("cat /var/my-state/test")
+        assert exitcode == 0, err
+        assert out == "dream2nix\n", out
 
-    # check for errors
-    exitcode, out, err = qga.run("cat /var/my-state/error")
-    assert exitcode == 1, out
+        # check for errors
+        exitcode, out, err = qga.run("cat /var/my-state/error")
+        assert exitcode == 1, out
 
-    # check all systemd services are OK, or print details
-    exitcode, out, err = qga.run(
-        "systemctl --failed | tee /tmp/yolo | grep -q '0 loaded units listed' || ( cat /tmp/yolo && false )"
-    )
-    assert exitcode == 0, out
+        # check all systemd services are OK, or print details
+        exitcode, out, err = qga.run(
+            "systemctl --failed | tee /tmp/yolo | grep -q '0 loaded units listed' || ( cat /tmp/yolo && false )"
+        )
+        assert exitcode == 0, out
 
-    # use qmp to shutdown the machine (prevent zombie qemu processes)
-    qmp = qmp_connect("my_machine", vm)
-    qmp.command("system_powerdown")
+        with qmp_connect("my_machine", vm) as qmp:
+            qmp.command("system_powerdown")
+    vm.join()