From f29ee64f76e353757e1db7a6501e29e65d953c95 Mon Sep 17 00:00:00 2001
From: Michael Hudson-Doyle <michael.hudson@canonical.com>
Date: Mon, 1 Apr 2019 20:46:46 +1300
Subject: [PATCH] Relax constraints on what can be deleted slightly

Allow a compound device (i.e. VG or raid) to be deleted if none of its
partitions are mounted or part of another device.

This makes it a lot easier to remove existing devices that probing for
existing partitions / compound devices can find.
---
 subiquity/models/filesystem.py | 48 ++++++++++++++++++++--------------
 1 file changed, 29 insertions(+), 19 deletions(-)

diff --git a/subiquity/models/filesystem.py b/subiquity/models/filesystem.py
index bf7d3297..e897a7d3 100644
--- a/subiquity/models/filesystem.py
+++ b/subiquity/models/filesystem.py
@@ -356,6 +356,35 @@ class _Device(_Formattable, ABC):
                 return True
         return False
 
+    @property
+    def _can_DELETE(self):
+        mounted_partitions = 0
+        for p in self._partitions:
+            if p.fs() and p.fs().mount():
+                mounted_partitions += 1
+            elif p.constructed_device():
+                cd = p.constructed_device()
+                return _(
+                    "Cannot delete {selflabel} as partition {partnum} is part "
+                    "of the {cdtype} {cdname}.").format(
+                        selflabel=self.label,
+                        partnum=p._number,
+                        cdtype=cd.desc(),
+                        cdname=cd.label,
+                        )
+        if mounted_partitions > 1:
+            return _(
+                "Cannot delete {selflabel} because it has {count} mounted "
+                "partitions.").format(
+                    selflabel=self.label,
+                    count=mounted_partitions)
+        elif mounted_partitions == 1:
+            return _(
+                "Cannot delete {selflabel} because it has 1 mounted partition."
+                ).format(selflabel=self.label)
+        else:
+            return _generic_can_DELETE(self)
+
 
 @attr.s(cmp=False)
 class Disk(_Device):
@@ -574,15 +603,6 @@ class Raid(_Device):
         self._constructed_device is None)
     _can_REMOVE = property(_generic_can_REMOVE)
 
-    @property
-    def _can_DELETE(self):
-        if len(self._partitions) > 0:
-            return _(
-                "Cannot delete {selflabel} because it has partitions.").format(
-                    selflabel=self.label)
-        else:
-            return _generic_can_DELETE(self)
-
     @property
     def ok_for_raid(self):
         if self._fs is not None:
@@ -647,16 +667,6 @@ class LVM_VolGroup(_Device):
 
     _can_CREATE_LV = Disk._can_PARTITION
 
-    @property
-    def _can_DELETE(self):
-        if len(self._partitions) > 0:
-            return _(
-                "Cannot delete {selflabel} because it has logical "
-                "volumes.").format(
-                    selflabel=self.label)
-        else:
-            return _generic_can_DELETE(self)
-
     ok_for_raid = False
     ok_for_lvm_vg = False