[meld] dirdiff: Minor refactoring of state filter patch

[Kai Willadsen <kaiw src gnome org>]

commit fe0b5974f6cac9010db06e82c131fcc458c5d8ec
Author: Kai Willadsen <kai willadsen gmail com>
Date:   Sun Jan 12 06:47:15 2014 +1000

    dirdiff: Minor refactoring of state filter patch

 meld/dirdiff.py |   19 +++++++++----------
 1 files changed, 9 insertions(+), 10 deletions(-)
---
diff --git a/meld/dirdiff.py b/meld/dirdiff.py
index ec2aebc..6bc4fe5 100644
--- a/meld/dirdiff.py
+++ b/meld/dirdiff.py
@@ -801,25 +801,24 @@ class DirDiff(melddoc.MeldDoc, gnomeglade.Component):
                     child = self.model.add_entries(it, entries)
                     differences |= self._update_item_state(child)
             else:
-                all_present = False not in [ os.path.exists(f) for f in roots ]
-                all_dir = False not in [ os.path.isdir(f) for f in roots ]
-                if (not all_present) or (not all_dir) or (tree.STATE_NORMAL in self.state_filters):
+                all_dir = all(os.path.isdir(f) for f in roots)
+                if (not all_dir) or (tree.STATE_NORMAL in self.state_filters):
                     self.model.add_empty(it)
-                    if self.model.iter_parent(it) == None:
+                    if self.model.iter_parent(it) is None:
                         expanded.add(rootpath)    # expand rootpath to show entire tree is empty
                 else:
-                    # assert ( roots all_present and all_dir and all_empty, STATE_NORMAL not in 
state_filters )
+                    # assert ( roots all_dir and all_empty, STATE_NORMAL not in state_filters )
 
                     # roots (and all their ancestors to top of tree) were let through in _filter_on_state()
                     # although STATE_NORMAL is disabled, so that their contents could be compared; as roots
                     # turned out empty their (and every empty ancestor's) branch in the tree can be removed
 
-                    assert (it != None) and (not self.model.iter_has_child(it))
+                    assert (it is not None) and (not self.model.iter_has_child(it))
                     while not self.model.iter_has_child(it):
-                        if self.model.iter_next(it) == None:
+                        if self.model.iter_next(it) is None:
                             # all siblings of it have been processed, none are left on the todo stack
                             parent = self.model.iter_parent(it)
-                            if parent == None:             # don't remove top of the tree
+                            if parent is None:             # don't remove top of the tree
                                 self.model.add_empty(it)
                                 expanded.add(rootpath)     # expand roothpath to show entire tree is empty
                                 break
@@ -831,8 +830,8 @@ class DirDiff(melddoc.MeldDoc, gnomeglade.Component):
                             self.model.remove(it)   # all paths of sibling dirs still on the stack are now 
invalid!
                             index = 0
                             # siblings that are on the stack, all occupy the top positions (in reverse order)
-                            while it != None:
-                                one_dir = True in [ os.path.isdir(f) for f in self.model.value_paths(it) ]
+                            while it is not None:
+                                one_dir = any(os.path.isdir(f) for f in self.model.value_paths(it))
                                 if one_dir:
                                     index += 1
                                     todo[-index] = self.model.get_path(it)   # correct the path for this 
sibling