[gobject-introspection] giscanner: simplify the MainTransformer().transform() method

[Dieter Verfaillie <dieterv src gnome org>]

commit 0dbd46680a7fac7ac74c2945e23b95dd04ff79dc
Author: Dieter Verfaillie <dieterv optionexplicit be>
Date:   Thu Apr 25 17:08:56 2013 +0200

    giscanner: simplify the MainTransformer().transform() method
    
    The ast.Namespace.names instance attribute is an OrderedDict
    which itself is a specialised dict() subclass. There are any
    number of ways to test if a dict() is empty or not. Creating
    a copy of it's keys by iterating over them just to count the
    number of items in the copy is not the most elegant way though.
    
    https://bugzilla.gnome.org/show_bug.cgi?id=699533

 giscanner/maintransformer.py |   10 ++++------
 1 files changed, 4 insertions(+), 6 deletions(-)
---
diff --git a/giscanner/maintransformer.py b/giscanner/maintransformer.py
index 6cf5a00..d2a8be7 100644
--- a/giscanner/maintransformer.py
+++ b/giscanner/maintransformer.py
@@ -48,12 +48,10 @@ class MainTransformer(object):
     # Public API
 
     def transform(self):
-        contents = list(self._namespace.itervalues())
-        if len(contents) == 0:
-            message.fatal("""Namespace is empty; likely causes are:
-* Not including .h files to be scanned
-* Broken --identifier-prefix
-""")
+        if not self._namespace.names:
+            message.fatal('Namespace is empty; likely causes are:\n'
+                          '* Not including .h files to be scanned\n'
+                          '* Broken --identifier-prefix')
 
         # Some initial namespace surgery
         self._namespace.walk(self._pass_fixup_hidden_fields)