fstab: Use 'mount_type' when writing filesystem type to fstab

FOr some formats the 'type' value is not valid for mounting/fstab,
for example for Stratis devices we internally use 'stratis xfs'
but we need to use 'xfs' for mounting and fstab.

blivet/fstab.py

@@ -396,7 +396,11 @@ def entry_from_device(self, device):
         entry.spec = self._get_spec(device)
         if entry.spec is None:
             entry.spec = getattr(device, "fstab_spec", None)
-        entry.vfstype = device.format.type
+
+        if hasattr(device.format, "mount_type") and device.format.mount_type is not None:
+            entry.vfstype = device.format.mount_type
+        else:
+            entry.vfstype = device.format.type
 
         return entry
 
@@ -434,7 +438,10 @@ def entry_from_action(self, action):
         if entry.spec is None:
             entry.spec = getattr(action.device, "fstab_spec", None)
 
-        entry.vfstype = action.device.format.type
+        if hasattr(action.device.format, "mount_type") and action.device.format.mount_type is not None:
+            entry.vfstype = action.device.format.mount_type
+        else:
+            entry.vfstype = action.device.format.type
 
         return entry
 

tests/unit_tests/fstab_test.py

@@ -8,8 +8,9 @@
 import copy
 
 from blivet.fstab import FSTabManager, FSTabEntry, HAVE_LIBMOUNT
-from blivet.devices import DiskDevice
+from blivet.devices import DiskDevice, StratisPoolDevice, StratisFilesystemDevice
 from blivet.formats import get_format
+from blivet.size import Size
 from blivet import Blivet
 
 FSTAB_WRITE_FILE = "/tmp/test-blivet-fstab2"
@@ -100,6 +101,15 @@ def test_entry_from_device(self):
         _entry = self.fstab.entry_from_device(device)
         self.assertEqual(_entry, FSTabEntry('/dev/test_device', '/media/fstab_test', 'ext4', None, 0, 0))
 
+    def test_entry_from_device_stratis(self):
+        pool = StratisPoolDevice("testpool", parents=[], exists=True)
+        device = StratisFilesystemDevice("testfs", parents=[pool], size=Size("1 GiB"), exists=True)
+        device.format = get_format("stratis xfs")
+        device.format.mountpoint = "/media/fstab_test"
+
+        _entry = self.fstab.entry_from_device(device)
+        self.assertEqual(_entry, FSTabEntry('/dev/stratis/testpool/testfs', '/media/fstab_test', 'xfs', None, 0, 0))
+
     def test_update(self):
 
         # Reset table