Fix: cgi.FieldStorage had a misleading implementation of __nonzero__ …

…and returned False for bool(request.files.name). This now returns True for existing files.

Thanks to Pascal Rosin via Twitter

bottle.py

@@ -122,6 +122,11 @@ def touni(s, enc='utf8', err='strict'):
     class NCTextIOWrapper(TextIOWrapper):
         def close(self): pass # Keep wrapped buffer open.
 
+# The truth-value of cgi.FieldStorage is misleading.
+class FieldStorage(cgi.FieldStorage):
+    def __nonzero__(self):
+        return bool(self.list or self.file)
+
 # A bug in functools causes it to break if the wrapper is an instance method
 def update_wrapper(wrapper, wrapped, *a, **ka):
     try: functools.update_wrapper(wrapper, wrapped, *a, **ka)
@@ -1092,7 +1097,7 @@ def POST(self):
                                          newline='\n')
         elif py3k:
             args['encoding'] = 'ISO-8859-1'
-        data = cgi.FieldStorage(**args)
+        data = FieldStorage(**args)
         for item in (data.list or [])[:self.MAX_PARAMS]:
             post[item.name] = item if item.filename else item.value
         return post

test/test_environ.py

@@ -285,6 +285,8 @@ def test_multipart(self):
         self.assertTrue('file2' in request.files)
         self.assertTrue('file2' not in request.forms)
         self.assertEqual('filename2.py', request.POST['file2'].filename)
+        self.assertTrue(request.files.file2)
+        self.assertFalse(request.files.file77)
         # UTF-8 files
         x = request.POST['file2'].file.read()
         if (3,2,0) > sys.version_info >= (3,0,0):