[cronet] make startNetLogToFile write to correct file

components/cronet/ios/test/cronet_netlog_test.mm

+// 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.
+
+#import <Cronet/Cronet.h>
+#import <Foundation/Foundation.h>
+
+#include "base/logging.h"

[mef, 2016/11/17 15:58:48]

IWYU - remove unused includes.

[lilyhoughton, 2016/11/22 20:48:42]

Done.

+#include "base/mac/scoped_nsobject.h"
+#include "base/strings/sys_string_conversions.h"
+#include "components/cronet/ios/test/quic_test_server.h"
+#include "components/cronet/ios/test/test_server.h"
+#include "net/base/mac/url_conversions.h"
+#include "net/base/net_errors.h"
+#include "net/cert/mock_cert_verifier.h"
+#include "testing/gtest/include/gtest/gtest.h"
+#include "testing/gtest_mac.h"
+#include "url/gurl.h"
+
+namespace cronet {
+
+void StartCronetIfNecessary();
+
+class NetLogTest : public ::testing::Test {
+ protected:
+  NetLogTest() {}
+  ~NetLogTest() override {}
+
+  void SetUp() override { StartCronetIfNecessary(); }
+};
+
+TEST(NetLogTest, OpenFile) {
+  bool netlog_started =
+      [Cronet startNetLogToFile:@"cronet_netlog.json" logBytes:YES];
+  [Cronet stopNetLog];
+
+  EXPECT_TRUE(netlog_started);

[kapishnikov, 2016/11/18 22:17:27]

Can we check that the file was created? The file name should be unique in that
case.

[lilyhoughton, 2016/12/02 16:30:07]

Done.

+}
+
+TEST(NetLogTest, NonExistantDir) {
+  NSString* notdir = [[[NSProcessInfo processInfo] globallyUniqueString]
+      stringByAppendingString:@"/netlog.json"];
+  bool netlog_started = [Cronet startNetLogToFile:notdir logBytes:NO];
+
+  EXPECT_FALSE(netlog_started);
+}
+
+TEST(NetLogTest, EmptyFilename) {
+  bool netlog_started = [Cronet startNetLogToFile:@"" logBytes:NO];
+
+  EXPECT_FALSE(netlog_started);
+}
+}