diff --git a/tools/sp-rand/unit_tests/test_cleanup.py b/tools/sp-rand/unit_tests/test_cleanup.py
index c54c53e..c3efb2d 100644
--- a/tools/sp-rand/unit_tests/test_cleanup.py
+++ b/tools/sp-rand/unit_tests/test_cleanup.py
@@ -5,7 +5,7 @@
 import pathlib
 import tempfile
 
-from typing import DefaultDict, Dict, List, NamedTuple, Tuple  # noqa: H301
+from typing import DefaultDict, Dict, List, NamedTuple  # noqa: H301
 
 import pytest
 
@@ -15,37 +15,58 @@
 from sp_rand import defs as r_defs
 
 
-T_ATTACHED = {
-    False: ["something-else", "testvol-42"],
-    True: ["testvol-9000", "another.snapshot", "testvol-616", "some-testvol-12"],
-}
+class VolSnapData(NamedTuple):
+    """Test data: what volumes and snapshots should be shown as attached."""
+
+    volumes: List[str]
+    snapshots: List[str]
+
+
+class ExportsData(NamedTuple):
+    """Test data: which volumes are exported to an initiator."""
+
+    portal_group: str
+    volume_name: str
+
+
+class TargetData(NamedTuple):
+    """Test data: an iSCSI target record for a StorPool volume."""
+
+    name: str
+    volume: str
+
+
+T_ATTACHED = VolSnapData(
+    volumes=["something-else", "testvol-42"],
+    snapshots=["testvol-9000", "another.snapshot", "testvol-616", "some-testvol-12"],
+)
 
 T_EXPORTED = {
     "beleriand": [
-        ("neighbors", "testvol-451"),
-        ("ours", "something-else"),
-        ("ours", "testvol-616"),
+        ExportsData(portal_group="neighbors", volume_name="testvol-451"),
+        ExportsData(portal_group="ours", volume_name="something-else"),
+        ExportsData(portal_group="ours", volume_name="testvol-616"),
     ],
-    "gondor": [("ours", "testvol-12")],
+    "gondor": [ExportsData(portal_group="ours", volume_name="testvol-12")],
 }
 
 T_TARGETS = {
-    1: {"name": "ouriqn:target-something-else", "volume": "something-else"},
-    2: {"name": "ouriqn:target-testvol-12", "volume": "testvol-12"},
-    3: {"name": "ouriqn:target-testvol-616", "volume": "testvol-616"},
-    4: {"name": "neiqn:whee-testvol-451", "volume": "testvol-451"},
+    1: TargetData(name="ouriqn:target-something-else", volume="something-else"),
+    2: TargetData(name="ouriqn:target-testvol-12", volume="testvol-12"),
+    3: TargetData(name="ouriqn:target-testvol-616", volume="testvol-616"),
+    4: TargetData(name="neiqn:whee-testvol-451", volume="testvol-451"),
 }
 
-T_VOLS = {
-    False: ["something-else", "testvol-42", "testvol-451"],
-    True: [
+T_VOLS = VolSnapData(
+    volumes=["something-else", "testvol-42", "testvol-451"],
+    snapshots=[
         "another.snapshot",
         "testvol-616",
         "testvol-9000",
         "some-testvol-12",
         "yet.another.thing",
     ],
-}
+)
 
 
 def test_parse_file() -> None:
@@ -120,24 +141,28 @@
 class MockApi:
     """Mock the StorPool API."""
 
-    attached: Dict[bool, List[str]]
-    exported: Dict[str, List[Tuple[str, str]]]
+    attached: VolSnapData
+    exported: Dict[str, List[ExportsData]]
     invoked: DefaultDict[str, int]
-    targets: Dict[int, Dict[str, str]]
-    vols: Dict[bool, List[str]]
+    targets: Dict[int, TargetData]
+    vols: VolSnapData
 
     def __init__(
         self,
-        attached: Dict[bool, List[str]],
-        exported: Dict[str, List[Tuple[str, str]]],
-        targets: Dict[int, Dict[str, str]],
-        vols: Dict[bool, List[str]],
+        attached: VolSnapData,
+        exported: Dict[str, List[ExportsData]],
+        targets: Dict[int, TargetData],
+        vols: VolSnapData,
     ) -> None:
         """Store deep copies of the passed definitions."""
-        self.attached = {key: list(value) for key, value in attached.items()}
+        self.attached = VolSnapData(
+            volumes=list(attached.volumes), snapshots=list(attached.snapshots)
+        )
         self.exported = {key: list(value) for key, value in exported.items()}
-        self.targets = {key: dict(value) for key, value in targets.items()}
-        self.vols = {key: list(value) for key, value in vols.items()}
+        self.targets = dict(targets)
+        self.vols = VolSnapData(
+            volumes=list(vols.volumes), snapshots=list(vols.snapshots)
+        )
         self.invoked = collections.defaultdict(lambda: 0)
 
     # pylint: disable=invalid-name
@@ -149,18 +174,18 @@
             sptypes.AttachmentDesc(
                 volume=name, snapshot=False, client=11, rights="rw", pos=0
             )
-            for name in self.attached[False]
+            for name in self.attached.volumes
         ] + [
             sptypes.AttachmentDesc(
                 volume=name, snapshot=True, client=11, rights="ro", pos=0
             )
-            for name in self.attached[True]
+            for name in self.attached.snapshots
         ]
 
     def iSCSIConfig(self) -> sptypes.iSCSIConfig:
         """Return the current view of the iSCSI configuration."""
         self.invoked["iSCSIConfig"] += 1
-        target_dict = {tgt["volume"]: tgt["name"] for tgt in self.targets.values()}
+        target_dict = {tgt.volume: tgt.name for tgt in self.targets.values()}
 
         return sptypes.iSCSIConfig(
             iscsi=sptypes.iSCSIConfigData(
@@ -173,7 +198,8 @@
                         nets=[],
                         exports=[
                             sptypes.iSCSIExport(
-                                portalGroup=exp[0], target=target_dict[exp[1]]
+                                portalGroup=exp.portal_group,
+                                target=target_dict[exp.volume_name],
                             )
                             for exp in explist
                         ],
@@ -184,8 +210,8 @@
                 targets={
                     tid: sptypes.iSCSITarget(
                         currentControllerId=65535,
-                        name=tgt["name"],
-                        volume=tgt["volume"],
+                        name=tgt.name,
+                        volume=tgt.volume,
                     )
                     for tid, tgt in self.targets.items()
                 },
@@ -201,14 +227,16 @@
             tgtdel = cmd.deleteTarget
             if expdel is not None:
                 initiator = self.exported[expdel.initiator]
-                data = (expdel.portalGroup, expdel.volumeName)
+                data = ExportsData(
+                    portal_group=expdel.portalGroup, volume_name=expdel.volumeName
+                )
                 assert data in initiator
                 initiator.remove(data)
             elif tgtdel is not None:
                 found = [
                     tid
                     for tid, tgt in self.targets.items()
-                    if tgt["volume"] == tgtdel.volumeName
+                    if tgt.volume == tgtdel.volumeName
                 ]
                 assert len(found) == 1
                 del self.targets[found[0]]
@@ -222,38 +250,35 @@
         for item in req.reassign:
             if isinstance(item, sptypes.VolumeReassignDesc):
                 assert item.volume.startswith("testvol-")
-                self.attached[False].remove(item.volume)
+                self.attached.volumes.remove(item.volume)
             else:
                 assert isinstance(item, sptypes.SnapshotReassignDesc)
                 assert item.snapshot.startswith("testvol-")
-                self.attached[True].remove(item.snapshot)
+                self.attached.snapshots.remove(item.snapshot)
 
             assert item.detach == [11]
 
     def volumesList(self) -> List[MockVolumeSummary]:
         """Return the current view of the available volumes."""
         self.invoked["volumesList"] += 1
-        return [MockVolumeSummary(name=name) for name in self.vols[False]]
+        return [MockVolumeSummary(name=name) for name in self.vols.volumes]
 
     def snapshotsList(self) -> List[MockVolumeSummary]:
         """Return the current view of the available snapshots."""
         self.invoked["snapshotsList"] += 1
-        return [MockVolumeSummary(name=name) for name in self.vols[True]]
-
-    def _volumeDelete(self, name: str, snapshot: bool) -> None:
-        """Remove a snapshot or a volume from our view."""
-        assert name not in self.attached[snapshot]
-        self.vols[snapshot].remove(name)
+        return [MockVolumeSummary(name=name) for name in self.vols.snapshots]
 
     def volumeDelete(self, name: str) -> None:
         """Remove a volume from our view."""
         self.invoked["volumeDelete"] += 1
-        self._volumeDelete(name, False)
+        assert name not in self.attached.volumes
+        self.vols.volumes.remove(name)
 
     def snapshotDelete(self, name: str) -> None:
         """Remove a snapshot from our view."""
         self.invoked["snapshotDelete"] += 1
-        self._volumeDelete(name, True)
+        assert name not in self.attached.snapshots
+        self.vols.snapshots.remove(name)
 
 
 def test_remove_volumes() -> None:
@@ -265,23 +290,31 @@
 
     r_cleanup.remove_volumes(cfg, mock_api, "testvol-")
 
-    assert mock_api.attached == {
-        key: [name for name in value if not name.startswith("testvol-")]
-        for key, value in T_ATTACHED.items()
-    }
+    assert mock_api.attached == VolSnapData(
+        volumes=[
+            name for name in T_ATTACHED.volumes if not name.startswith("testvol-")
+        ],
+        snapshots=[
+            name for name in T_ATTACHED.snapshots if not name.startswith("testvol-")
+        ],
+    )
     assert mock_api.exported == {
-        initiator: [item for item in exports if not item[1].startswith("testvol-")]
+        initiator: [
+            item for item in exports if not item.volume_name.startswith("testvol-")
+        ]
         for initiator, exports in T_EXPORTED.items()
     }
     assert mock_api.targets == {
         tid: tgt
         for tid, tgt in T_TARGETS.items()
-        if not tgt["volume"].startswith("testvol-")
+        if not tgt.volume.startswith("testvol-")
     }
-    assert mock_api.vols == {
-        key: [name for name in value if not name.startswith("testvol-")]
-        for key, value in T_VOLS.items()
-    }
+    assert mock_api.vols == VolSnapData(
+        volumes=[name for name in T_VOLS.volumes if not name.startswith("testvol-")],
+        snapshots=[
+            name for name in T_VOLS.snapshots if not name.startswith("testvol-")
+        ],
+    )
 
     assert mock_api.invoked == {
         "attachmentsList": 1,