[PATCH 4/4] Remove partitions in reverse order when clearing disks.

[David Lehman <dlehman redhat com>]

This helps us to avoid parted's renumbering nonsense.

This patch also streamlines clearPartitions so that it removes the
partitions inside the loop instead of building a list and iterating over
it separately to remove the partitions.
---
 partIntfHelpers.py      |   41 ++++++++++++++++++++++++++++-------------
 storage/partitioning.py |   14 +++++---------
 2 files changed, 33 insertions(+), 22 deletions(-)

diff --git a/partIntfHelpers.py b/partIntfHelpers.py
index a68704f..cf136fb 100644
--- a/partIntfHelpers.py
+++ b/partIntfHelpers.py
@@ -144,7 +144,11 @@ def doDeleteDevice(intf, storage, device, confirm=1, quiet=0):
     return True
 
 def doDeleteDependentDevices(intf, storage, device, confirm=1, quiet=0):
-    """ Remove all devices/partitions currently on device """
+    """ Remove all devices/partitions currently on device.
+
+            device -- a partitioned device such as a disk
+
+     """
     if confirm:
 	rc = intf.messageWindow(_("Confirm Delete"),
 				_("You are about to delete all partitions on "
@@ -155,20 +159,31 @@ def doDeleteDependentDevices(intf, storage, device, confirm=1, quiet=0):
 	if not rc:
 	    return False
 
-    deps = storage.deviceDeps(device)
-    if not deps:
-        # nothing to do
+    immutable = []
+    partitions = [p for p in storage.partitions if p.disk == device]
+    if not partitions:
         return False
 
-    immutable = []
-    while deps:
-        leaves = [d for d in deps if d.isleaf]
-        for leaf in leaves:
-            if storage.deviceImmutable(leaf):
-                immutable.append(leaf.path)
-            else:
-                storage.destroyDevice(leaf)
-            deps.remove(leaf)
+    partitions.sort(key=lambda p: p.partedPartition.number, reverse=True)
+    for p in partitions:
+        deps = storage.deviceDeps(p)
+        clean = True    # true if part and its deps were removed
+        while deps:
+            leaves = [d for d in deps if d.isleaf]
+            for leaf in leaves:
+                if storage.deviceImmutable(leaf):
+                    immutable.append(leaf.path)
+                    clean = False
+                else:
+                    storage.destroyDevice(leaf)
+                deps.remove(leaf)
+
+        if storage.deviceImmutable(p):
+            immutable.append(p.path)
+            clean = False
+
+        if clean:
+            storage.destroyDevice(p)
 
     if immutable and not quiet:
         remaining = "\t" + "\n\t".join(immutable) + "\n"
diff --git a/storage/partitioning.py b/storage/partitioning.py
index e1c2a8d..80724d6 100644
--- a/storage/partitioning.py
+++ b/storage/partitioning.py
@@ -324,8 +324,11 @@ def clearPartitions(storage):
 
     # we are only interested in partitions that physically exist
     partitions = [p for p in storage.partitions if p.exists]
-    disks = []  # a list of disks from which we've removed partitions
-    clearparts = [] # list of partitions we'll remove
+    # Sort partitions by descending partition number to minimize confusing
+    # things like multiple "destroy sda5" actions due to parted renumbering
+    # partitions. This can still happen through the UI but it makes sense to
+    # avoid it where possible.
+    partitions.sort(key=lambda p: p.partedPartition.number, reverse=True)
     for part in partitions:
         log.debug("clearpart: looking at %s" % part.name)
         if not shouldClear(part, storage.clearPartType, storage.clearPartDisks):
@@ -345,13 +348,6 @@ def clearPartitions(storage):
                 devices.remove(leaf)
 
         log.debug("partitions: %s" % [p.getDeviceNodeName() for p in part.partedPartition.disk.partitions])
-        disk_name = os.path.basename(part.partedPartition.disk.device.path)
-        if disk_name not in disks:
-            disks.append(disk_name)
-
-        clearparts.append(part)
-
-    for part in clearparts:
         storage.destroyDevice(part)
 
     # now remove any empty extended partitions
-- 
1.6.0.6