WIP ZFS-ng: test chain of VDI clones and their destuction

FIXME:
* cloning a VDI without a snapshot is not implemented yet

tests/storage/zfs_ng/test_zfs_sr.py

@@ -125,3 +125,29 @@ def test_vdi_and_snaps_destroy_intermediate_vdi(self, vdi_and_snaps_chain):
         vdi.destroy()
         # tell fixture we destroyed that one
         vdi_and_snaps_chain[2:3] = []
+
+@pytest.fixture(scope='package')
+def vdi_chain(zfs_sr):
+    """ A chain of VDI clones on first host. """
+    vdis = [zfs_sr.create_vdi('ZFS-local-VDI-test')]
+    for i in range(2):
+        vdis.append(vdis[-1].clone())
+    yield vdis
+    # teardown
+    for vdi in reversed(vdis):
+        vdi.destroy()
+
+@pytest.mark.xfail
+@pytest.mark.usefixtures("vdi_chain")
+class TestZfsngSrVdiDestroy:
+    def test_destroy(self, vdi_chain):
+        assert len(vdi_chain) == 3
+
+    def test_destroy_last(self, vdi_chain):
+        vdi_chain[-1].destroy()
+
+    def test_destroy_first(self, vdi_chain):
+        vdi_chain[0].destroy()
+
+    def test_destroy_intermediate(self, vdi_chain):
+        vdi_chain[1].destroy()