[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"
+#include "base/mac/scoped_nsobject.h"
+#include "base/strings/sys_string_conversions.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];

[mef, 2016/12/09 18:30:41]

this may behave differently during first and consecutive runs.

[lilyhoughton, 2016/12/09 19:42:50]

Not sure how to account for that besides just having a second identical test?

+  [Cronet stopNetLog];
+
+  EXPECT_TRUE(netlog_started);
+}
+
+TEST(NetLogTest, CreateFile) {
+  NSString* filename = [[[NSProcessInfo processInfo] globallyUniqueString]
+      stringByAppendingString:@"_netlog.json"];
+  bool netlog_started = [Cronet startNetLogToFile:filename logBytes:YES];
+  [Cronet stopNetLog];
+
+  bool file_created = [[NSFileManager defaultManager]
+      fileExistsAtPath:[Cronet netLogPath:filename]];
+
+  EXPECT_TRUE(netlog_started);
+  EXPECT_TRUE(file_created);

[mef, 2016/12/09 18:30:41]

Delete that [Cronet netLogPath:filename] at the end?

[lilyhoughton, 2016/12/09 19:42:50]

Done.

+}
+
+TEST(NetLogTest, NonExistantDir) {

[mef, 2016/12/09 18:30:41]

Add test for creating netlog in existing directory? 

[lilyhoughton, 2016/12/09 19:42:50]

Done.

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

[mef, 2016/12/09 18:30:41]

Add test for passing absolute path name.

[lilyhoughton, 2016/12/09 19:42:50]

Added a check to startNetLogToFile just to make sure, too.

+  bool netlog_started = [Cronet startNetLogToFile:@"" logBytes:NO];
+
+  EXPECT_FALSE(netlog_started);
+}
+}