[virt-tools-list] [virt-manager PATCH] inspection: fix check of null icon

[Pino Toscano]

Recently the Python binding of libguestfs was adapted to properly use
bytes in APIs that return data, instead of (ab)using strings [1].
This change was done only when built for Python 3, which has this
distinct bytes and strings.

Because of that, now the 'icon == ""' (empty string) checks fail, using
whatever inspect_get_icon() returns, including empty arrays of bytes.
Hence, change the checks to use the length of the data as condition, as
also the libguestfs Python API documentation says.  Leave also the
checks for None, in the remote case the API will return None in the
future for no data.

[1] https://github.com/libguestfs/libguestfs/commit/0ee02e0117527b86a31b2a88a14994ce7f15571f
---
 virtManager/inspection.py | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/virtManager/inspection.py b/virtManager/inspection.py
index ea6123b8..fde48474 100644
--- a/virtManager/inspection.py
+++ b/virtManager/inspection.py
@@ -268,10 +268,10 @@ class vmmInspection(vmmGObject):
         if filesystems_mounted:
             # string containing PNG data
             icon = g.inspect_get_icon(root, favicon=0, highquality=1)
-            if icon == "" or icon is None:
+            if icon is None or len(icon) == 0:
                 # no high quality icon, try a low quality one
                 icon = g.inspect_get_icon(root, favicon=0, highquality=0)
-                if icon == "":
+                if icon is None or len(icon) == 0:
                     icon = None
 
             # Inspection applications.
-- 
2.20.1