[libfuzzer] Turn warnings from zipfile into errors while archiving seed corpus.

testing/libfuzzer/archive_corpus.py

 #!/usr/bin/python2
 #
 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 """Archive corpus file into zip and generate .d depfile.
 
 Invoked by GN from fuzzer_test.gni.
 """
 
 from __future__ import print_function
 import argparse
 import os
 import sys
+import warnings
 import zipfile
 
 
 def main():
   parser = argparse.ArgumentParser(description="Generate fuzzer config.")
   parser.add_argument('--corpus', required=True)
   parser.add_argument('--output', required=True)
   parser.add_argument('--fuzzer', required=True)
   args = parser.parse_args()
 
   corpus_files = []
 
   for (dirpath, _, filenames) in os.walk(args.corpus):
     for filename in filenames:
       full_filename = os.path.join(dirpath, filename)
       corpus_files.append(full_filename)
 
   with zipfile.ZipFile(args.output, 'w') as z:
-    for corpus_file in corpus_files:
-        z.write(corpus_file, os.path.basename(corpus_file))
+    # Turn warnings into errors to interrupt the build: crbug.com/653920.
+    with warnings.catch_warnings():
+      warnings.simplefilter("error")
+      for i, corpus_file in enumerate(corpus_files):
+        # To avoid duplication of filenames inside the archive, use numbers.
+        arcname = '%016d' % i

[mmoroz, 2016/11/29 13:53:41]

I thought to use subdirectory_name + '_' + os.path.basename(corpus_file), but
names of corpus files are not important, so that complication wouldn't make
sense.

+        z.write(corpus_file, arcname)
 
 
 if __name__ == '__main__':
   main()