Fixing how --gtest-filter-file handles negative patterns.

build/android/pylib/gtest/gtest_test_instance.py

 # Copyright 2014 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.
 
 import HTMLParser
 import logging
 import os
 import re
 import tempfile
 import xml.etree.ElementTree
@@ skipping 180 matching lines @@
 
       results.append(base_test_result.BaseTestResult(
           '%s.%s' % (suite_name, case_name),
           result_type,
           int(float(testcase.attrib['time']) * 1000),
           log=('\n'.join(log) if log else '')))
 
   return results
 
 
+# Converts file contents described by //testing/buildbot/filters/README.md

[jbudorick, 2016/11/03 18:21:18]

Nit: make this a docstring, please.

[Łukasz Anforowicz, 2016/11/03 19:34:38]

Ooops.  Thanks for catching this.  I guess I've been doing too much C++ and too
little Python recently :-)

The docstring turned out to be relatively long, but I think this is okay.

+# into an argument for --gtest_filter command line parameter.
+def ConvertTestFilterFileIntoGTestFilterArgument(input_lines):
+  # Strip whitespace + skip empty lines and lines beginning with '#'.
+  stripped_lines = (l.strip() for l in input_lines)
+  filter_lines = list(l for l in stripped_lines if l and l[0] != '#')
+
+  # Split the tests into positive and negative patterns (gtest treats
+  # every pattern after the first '-' sign as an exclusion).
+  positive_patterns = ':'.join(l for l in filter_lines if l[0] != '-')
+  negative_patterns = ':'.join(l[1:] for l in filter_lines if l[0] == '-')
+  if negative_patterns:
+    negative_patterns = '-' + negative_patterns
+
+  # Join the filter lines into one, big --gtest_filter argument.
+  return positive_patterns + negative_patterns
+
+
 class GtestTestInstance(test_instance.TestInstance):
 
   def __init__(self, args, isolate_delegate, error_func):
     super(GtestTestInstance, self).__init__()
     # TODO(jbudorick): Support multiple test suites.
     if len(args.suite_name) > 1:
       raise ValueError('Platform mode currently supports only 1 gtest suite')
     self._extract_test_list_from_filter = args.extract_test_list_from_filter
     self._shard_timeout = args.shard_timeout
     self._suite = args.suite_name[0]
@@ skipping 34 matching lines @@
         self._shard_timeout = 10 * self._shard_timeout
 
     if not self._apk_helper and not self._exe_dist_dir:
       error_func('Could not find apk or executable for %s' % self._suite)
 
     self._data_deps = []
     if args.test_filter:
       self._gtest_filter = args.test_filter
     elif args.test_filter_file:
       with open(args.test_filter_file, 'r') as f:
-        # Strip whitespace + skip empty lines and lines beginning with '#'.
-        # This should be consistent with processing of
-        # --test-launcher-filter-file in base/test/launcher/test_launcher.cc.
-        stripped_lines = (l.strip() for l in f)
-        filter_lines = (l for l in stripped_lines if l and l[0] != '#')
-        # Join the filter lines into one, big --gtest_filter argument.
-        self._gtest_filter = ':'.join(filter_lines)
+        self._gtest_filter = ConvertTestFilterFileIntoGTestFilterArgument(f)
     else:
       self._gtest_filter = None
 
     if (args.isolate_file_path and
         not isolator.IsIsolateEmpty(args.isolate_file_path)):
       self._isolate_abs_path = os.path.abspath(args.isolate_file_path)
       self._isolate_delegate = isolate_delegate
       self._isolated_abs_path = os.path.join(
           constants.GetOutDirectory(), '%s.isolated' % self._suite)
     else:
@@ skipping 151 matching lines @@
             if l and not l.startswith('#')]
 
     return '*-%s' % ':'.join(disabled_filter_items)
 
   #override
   def TearDown(self):
     """Clear the mappings created by SetUp."""
     if self._isolate_delegate:
       self._isolate_delegate.Clear()