Style and misc fixes to the script

src/objective-c/change-comments.py

-#!/usr/bin/python
+#!/usr/bin/env python2.7
+# Copyright 2015, Google Inc.
+# All rights reserved.
+#
+# Redistribution and use in source and binary forms, with or without
+# modification, are permitted provided that the following conditions are
+# met:
+#
+#     * Redistributions of source code must retain the above copyright
+# notice, this list of conditions and the following disclaimer.
+#     * Redistributions in binary form must reproduce the above
+# copyright notice, this list of conditions and the following disclaimer
+# in the documentation and/or other materials provided with the
+# distribution.
+#     * Neither the name of Google Inc. nor the names of its
+# contributors may be used to endorse or promote products derived from
+# this software without specific prior written permission.
+#
+# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+"""Change comments style of source files from // to /** */"""
 
 import re
 import sys
@@ -11,14 +41,12 @@ if len(sys.argv) < 2:
 for file_name in sys.argv[1:]:
 
   print("Modifying format of {file} comments in place...".format(
-      file = file_name,
+      file=file_name,
   ))
 
 
   # Input
 
-  lines = []
-
   with open(file_name, "r") as input_file:
     lines = input_file.readlines()
 
@@ -40,9 +68,9 @@ for file_name in sys.argv[1:]:
     output_lines.append(line)
 
   def flush_output():
-    with open(file_name, "w") as otuput_file:
+    with open(file_name, "w") as output_file:
       for line in output_lines:
-        otuput_file.write(line)
+        output_file.write(line)
 
 
   # Pattern matching
@@ -56,9 +84,7 @@ for file_name in sys.argv[1:]:
     return not is_comment(line)
 
   def next_line(predicate):
-    if not more_input_available():
-      return False
-    return predicate(peek())
+    return more_input_available() and predicate(peek())
 
 
   # Transformation