util: Fix generate_name start_num logic

We would start at start_num+1 which was confusing, fix it to do
the right thing.

virtinst/cloner.py

@@ -480,7 +480,7 @@ class Cloner(object):
         basename = self.original_guest
 
         match = re.search("-clone[1-9]*$", basename)
-        start_num = 0
+        start_num = 1
         if match:
             num_match = re.search("[1-9]+$", match.group())
             if num_match:

virtinst/storage.py

@@ -461,32 +461,15 @@ class StorageVolume(_StorageObject):
     Base class for building and installing libvirt storage volume xml
     """
     @staticmethod
-    def find_free_name(pool_object, basename,
-                       suffix="", collidelist=None, start_num=0):
+    def find_free_name(pool_object, basename, **kwargs):
         """
         Finds a name similar (or equal) to passed 'basename' that is not
-        in use by another pool
-
-        This function scans the list of existing Volumes on the passed or
-        looked up pool object for a collision with the passed name. If the
-        name is in use, it append "-1" to the name and tries again, then "-2",
-        continuing to 100000 (which will hopefully never be reached.") If
-        suffix is specified, attach it to the (potentially incremented) name
-        before checking for collision.
-
-        Ex name="test", suffix=".img" -> name-3.img
-
-        @param collidelist: An extra list of names to check for collision
-        @type collidelist: C{list}
-        @returns: A free name
-        @rtype: C{str}
+        in use by another pool. Extra params are passed to generate_name
         """
-        collidelist = collidelist or []
         pool_object.refresh(0)
-
-        return util.generate_name(basename, pool_object.storageVolLookupByName,
-                                  suffix, collidelist=collidelist,
-                                  start_num=start_num)
+        return util.generate_name(basename,
+                                  pool_object.storageVolLookupByName,
+                                  **kwargs)
 
     TYPE_FILE = getattr(libvirt, "VIR_STORAGE_VOL_FILE", 0)
     TYPE_BLOCK = getattr(libvirt, "VIR_STORAGE_VOL_BLOCK", 1)

virtinst/util.py

@@ -166,7 +166,7 @@ def validate_macaddr(val):
 
 
 def generate_name(base, collision_cb, suffix="", lib_collision=True,
-                  start_num=0, sep="-", force_num=False, collidelist=None):
+                  start_num=1, sep="-", force_num=False, collidelist=None):
     """
     Generate a new name from the passed base string, verifying it doesn't
     collide with the collision callback.
@@ -201,9 +201,13 @@ def generate_name(base, collision_cb, suffix="", lib_collision=True,
         else:
             return collision_cb(tryname)
 
-    for i in range(start_num, start_num + 100000):
+    numrange = range(start_num, start_num + 100000)
+    if not force_num:
+        numrange = [None] + numrange
+
+    for i in numrange:
         tryname = base
-        if i != start_num or force_num:
+        if i is not None:
             tryname += ("%s%d" % (sep, i))
         tryname += suffix