livemerge_test: fake prune_bitmaps errors

Add support to fake errors in prune_bitmaps calls
to the IRS fake class.

Signed-off-by: Albert Esteve <aesteve@redhat.com>

tests/virt/livemerge_test.py

@@ -17,6 +17,7 @@
 from vdsm.common.config import config
 from vdsm.common.units import GiB, MiB
 
+from vdsm.virt import errors
 from vdsm.virt import metadata
 from vdsm.virt import migration
 from vdsm.virt import thinp
@@ -889,6 +890,23 @@ def test_internal_merge():
     assert vm.volume_monitor.enabled
 
 
+def test_internal_merge_prune_error():
+    config = Config('internal-merge')
+    merge_params = config.values["merge_params"]
+
+    vm = RunningVM(config)
+
+    assert vm.query_jobs() == {}
+
+    # Simulate prune_bitmaps error.
+    error_msg = "Failed to remove bitmap"
+    vm.cif.irs.errors["prune_bitmaps"] = exception.RemoveBitmapError(error_msg)
+
+    with pytest.raises(errors.StorageUnavailableError) as e:
+        vm.merge(**merge_params)
+    assert error_msg in str(e)
+
+
 def test_extend_timeout_recover(fake_time):
     config = Config('active-merge')
     sd_id = config.values["drive"]["domainID"]

tests/virt/vmfakelib.py

@@ -41,6 +41,7 @@ def __init__(self):
         self.extend_requests = []
         self.sd_types = {}
         self.measure_info = {}
+        self.errors = {}
 
     def getDeviceVisibility(self, guid):
         pass
@@ -53,6 +54,9 @@ def inappropriateDevices(self, ident):
 
     @recorded
     def prune_bitmaps(self, sdUUID, imgUUID, volUUID, baseUUID):
+        error = self.errors.get("prune_bitmaps")
+        if error:
+            return response.error_raw(error.code, error.msg)
         return response.success(result=None)
 
     def measure(self, sdUUID, imgUUID, volUUID, dest_format, backing=True,