--- a/fetch.py	Mon Nov 14 22:12:49 2011 -0800
+++ b/fetch.py	Tue Nov 15 10:13:47 2011 -0800
@@ -60,7 +60,7 @@
 class FileFetcher(Fetcher):
     """fetch a single file"""
     # Note: subpath and clobber for single files are ignored
-  
+
     type = 'file'
 
     @classmethod
@@ -130,7 +130,7 @@
             # can only export with a subpath
             self.export(dest, subpath=self.subpath)
             return
-            
+
         if os.path.exists(dest):
             assert os.path.isdir(dest)
         else:
@@ -179,7 +179,7 @@
     def versioned(self, directory):
         return os.path.exists(os.path.join(directory, self.vcs_dir))
 
-        
+
 if which('hg'):
 
     class HgFetcher(VCSFetcher):
@@ -195,7 +195,7 @@
             if os.path.exists(dest):
                 assert os.path.isdir(dest)
             call([self.hg, 'clone', self.url, dest])
-            
+
         def update(self, dest):
             assert os.path.versioned(dest)
             assert os.path.exists(dest)
@@ -232,7 +232,7 @@
 __all__ += [i.__name__ for i in fetchers]
 
 class Fetch(object):
-  
+
     def __init__(self, fetchers=fetchers[:], relative_to=None, strict=True):
         self.fetchers = fetchers
         self.relative_to = relative_to
@@ -256,7 +256,8 @@
             # ensure all the required fetchers are available
             types = set([i['type'] for i in items])
             assert not [i for i in types
-                        if [True for fetcher in fetchers if fetcher.match(i)]]
+                        if not [True for fetcher in fetchers
+                                if fetcher.match(i)]]
 
         for item in items:
 
@@ -274,18 +275,21 @@
 def read_manifests(*manifests):
     """
     read some manifests and return the items
-    
+
     Format:
     %s
     """ % format_string
 
-    # sanity check
-    assert not [i for i in manifests if not os.path.exists(i)]
-
     retval = []
 
     for manifest in manifests:
-        for line in file(i).readlines():
+        if isinstance(manifest, basestring):
+            assert os.path.exists(manifest), "manifest '%s' not found" % manifest
+            f = file(manifest)
+        else:
+            f = manifest
+
+        for line in f.readlines():
             line = line.strip()
             if line.startswith('#') or not line:
                 continue
@@ -316,7 +320,7 @@
                 return description + '\n'
             else:
                 return ''
-  
+
     parser = optparse.OptionParser(usage=usage, description=__doc__, formatter=PlainDescriptionFormatter())
     parser.add_option('-o', '--output',
                       help="output relative to this location vs. the manifest location")
@@ -345,6 +349,9 @@
         parser.print_help()
         parser.exit()
 
+    # sanity check
+    assert not [i for i in args if not os.path.exists(i)]
+
     items = read_manifests(*args)
     fetch = Fetch(fetchers, strict=options.strict)
 
@@ -352,5 +359,5 @@
     fetch.fetch(*items)
 
 if __name__ == '__main__':
-    main()  
+    main()