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 #!/usr/bin/env python

 # This Source Code Form is subject to the terms of the Mozilla Public

 # License, v. 2.0. If a copy of the MPL was not distributed with this

 # file, You can obtain one at http://mozilla.org/MPL/2.0/.

 # Usage: check_source_count.py SEARCH_TERM COUNT ERROR_LOCATION REPLACEMENT [FILES...]

 #   Checks that FILES contains exactly COUNT matches of SEARCH_TERM. If it does

 #   not, an error message is printed, quoting ERROR_LOCATION, which should

 #   probably be the filename and line number of the erroneous call to

 #   check_source_count.py.

 from __future__ import print_function

 import sys

 import os

 import re

 search_string = sys.argv[1]

 expected_count = int(sys.argv[2])

 error_location = sys.argv[3]

 replacement = sys.argv[4]

 files = sys.argv[5:]

 details = {}

 count = 0

 for f in files:

     text = file(f).read()

     match = re.findall(search_string, text)

     if match:

         num = len(match)

         count += num

         details[f] = num

 if count == expected_count:

     print("TEST-PASS | check_source_count.py {0} | {1}"

           .format(search_string, expected_count))

 else:

     print("TEST-UNEXPECTED-FAIL | check_source_count.py {0} | "

           .format(search_string),

           end='')

     if count < expected_count:

         print("There are fewer occurrences of /{0}/ than expected. "

               "This may mean that you have removed some, but forgotten to "

               "account for it {1}.".format(search_string, error_location))

     else:

         print("There are more occurrences of /{0}/ than expected. We're trying "

               "to prevent an increase in the number of {1}'s, using {2} if "

               "possible. If it is unavoidable, you should update the expected "

               "count {3}.".format(search_string, search_string, replacement, 

                                  error_location))

     print("Expected: {0}; found: {1}".format(expected_count, count))

     for k in sorted(details):

         print("Found {0} occurences in {1}".format(details[k],k))

     sys.exit(-1)