Fix subtle flakiness from ZipTest.

chrome/common/zip_unittest.cc

 // Copyright (c) 2011 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.
 
 #include <set>
 
 #include "base/file_util.h"
 #include "base/path_service.h"
 #include "base/scoped_temp_dir.h"
 #include "base/string_util.h"
@@ skipping 81 matching lines @@
 }
 
 TEST_F(ZipTest, UnzipUncompressed) {
   TestUnzipFile(FILE_PATH_LITERAL("test_nocompress.zip"), true);
 }
 
 TEST_F(ZipTest, UnzipEvil) {
   FilePath path;
   ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &path));
   path = path.AppendASCII("zip").AppendASCII("evil.zip");
-  ASSERT_FALSE(zip::Unzip(path, test_dir_));
-  FilePath evil_file = test_dir_;
+  // Unzip the zip file into a sub directory of test_dir_ so evil.zip
+  // won't create a persistent file outside test_dir_ in case of a
+  // failure.
+  FilePath output_dir = test_dir_.AppendASCII("out");
+  ASSERT_FALSE(zip::Unzip(path, output_dir));
+  FilePath evil_file = output_dir;
   evil_file = evil_file.AppendASCII(
       "../levilevilevilevilevilevilevilevilevilevilevilevil");
   ASSERT_FALSE(file_util::PathExists(evil_file));
 }
 
 TEST_F(ZipTest, UnzipEvil2) {
   FilePath path;
   ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &path));
   path = path.AppendASCII("zip").AppendASCII("evil_via_invalid_utf8.zip");
-  ASSERT_TRUE(zip::Unzip(path, test_dir_));
-  FilePath evil_file = test_dir_;
+  // See the comment at UnzipEvil() for why we do this.
+  FilePath output_dir = test_dir_.AppendASCII("out");
+  ASSERT_TRUE(zip::Unzip(path, output_dir));
+  FilePath evil_file = output_dir;
   evil_file = evil_file.AppendASCII("../evil.txt");
   ASSERT_FALSE(file_util::PathExists(evil_file));
 }
 
 TEST_F(ZipTest, Zip) {
   FilePath src_dir;
   ASSERT_TRUE(PathService::Get(chrome::DIR_TEST_DATA, &src_dir));
   src_dir = src_dir.AppendASCII("zip").AppendASCII("test");
 
   ScopedTempDir temp_dir;
@@ skipping 11 matching lines @@
 
   ScopedTempDir temp_dir;
   ASSERT_TRUE(temp_dir.CreateUniqueTempDir());
   FilePath zip_file = temp_dir.path().AppendASCII("out.zip");
 
   EXPECT_TRUE(zip::Zip(src_dir, zip_file, false));
   TestUnzipFile(zip_file, false);
 }
 
 }  // namespace