Rewrite std::string("") to std::string(), Linux edition.

net/dns/host_resolver_impl_unittest.cc

 // Copyright (c) 2012 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 "net/dns/host_resolver_impl.h"
 
 #include <algorithm>
 #include <string>
 
 #include "base/bind.h"
@@ skipping 89 matching lines @@
 
   void AddRule(const std::string& hostname, AddressFamily family,
                const AddressList& result) {
     base::AutoLock lock(lock_);
     rules_[ResolveKey(hostname, family)] = result;
   }
 
   void AddRule(const std::string& hostname, AddressFamily family,
                const std::string& ip_list) {
     AddressList result;
-    int rv = ParseAddressList(ip_list, "", &result);
+    int rv = ParseAddressList(ip_list, std::string(), &result);
     DCHECK_EQ(OK, rv);
     AddRule(hostname, family, result);
   }
 
   void AddRuleForAllFamilies(const std::string& hostname,
                              const std::string& ip_list) {
     AddressList result;
-    int rv = ParseAddressList(ip_list, "", &result);
+    int rv = ParseAddressList(ip_list, std::string(), &result);
     DCHECK_EQ(OK, rv);
     AddRule(hostname, ADDRESS_FAMILY_UNSPECIFIED, result);
     AddRule(hostname, ADDRESS_FAMILY_IPV4, result);
     AddRule(hostname, ADDRESS_FAMILY_IPV6, result);
   }
 
   virtual int Resolve(const std::string& hostname,
                       AddressFamily address_family,
                       HostResolverFlags host_resolver_flags,
                       AddressList* addrlist,
                       int* os_error) OVERRIDE {
     base::AutoLock lock(lock_);
     capture_list_.push_back(ResolveKey(hostname, address_family));
     ++num_requests_waiting_;
     requests_waiting_.Broadcast();
     while (!num_slots_available_)
       slots_available_.Wait();
     DCHECK_GT(num_requests_waiting_, 0u);
     --num_slots_available_;
     --num_requests_waiting_;
     if (rules_.empty()) {
-      int rv = ParseAddressList("127.0.0.1", "", addrlist);
+      int rv = ParseAddressList("127.0.0.1", std::string(), addrlist);
       DCHECK_EQ(OK, rv);
       return OK;
     }
     ResolveKey key(hostname, address_family);
     if (rules_.count(key) == 0)
       return ERR_NAME_NOT_RESOLVED;
     *addrlist = rules_[key];
     return OK;
   }
 
@@ skipping 369 matching lines @@
   Request* req = CreateRequest("just.testing", 80);
   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
   EXPECT_EQ(OK, req->WaitForResult());
 
   EXPECT_TRUE(req->HasOneAddress("192.168.1.42", 80));
 
   EXPECT_EQ("just.testing", proc_->GetCaptureList()[0].hostname);
 }
 
 TEST_F(HostResolverImplTest, FailedAsynchronousLookup) {
-  proc_->AddRuleForAllFamilies("", "0.0.0.0");  // Default to failures.
+  proc_->AddRuleForAllFamilies(std::string(),
+                               "0.0.0.0");  // Default to failures.
   proc_->SignalMultiple(1u);
 
   Request* req = CreateRequest("just.testing", 80);
   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->WaitForResult());
 
   EXPECT_EQ("just.testing", proc_->GetCaptureList()[0].hostname);
 
   // Also test that the error is not cached.
   EXPECT_EQ(ERR_DNS_CACHE_MISS, req->ResolveFromCache());
@@ skipping 34 matching lines @@
 TEST_F(HostResolverImplTest, NumericIPv6Address) {
   // Resolve a plain IPv6 address.  Don't worry about [brackets], because
   // the caller should have removed them.
   Request* req = CreateRequest("2001:db8::1", 5555);
   EXPECT_EQ(OK, req->Resolve());
 
   EXPECT_TRUE(req->HasOneAddress("2001:db8::1", 5555));
 }
 
 TEST_F(HostResolverImplTest, EmptyHost) {
-  Request* req = CreateRequest("", 5555);
+  Request* req = CreateRequest(std::string(), 5555);
   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->Resolve());
 }
 
 TEST_F(HostResolverImplTest, LongHost) {
   Request* req = CreateRequest(std::string(4097, 'a'), 5555);
   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req->Resolve());
 }
 
 TEST_F(HostResolverImplTest, DeDupeRequests) {
   // Start 5 requests, duplicating hosts "a" and "b". Since the resolver_proc is
@@ skipping 741 matching lines @@
   EXPECT_TRUE(requests_[2]->HasAddress("::1", 80));
   EXPECT_EQ(1u, requests_[3]->NumberOfAddresses());
   EXPECT_TRUE(requests_[3]->HasAddress("192.168.1.101", 80));
 }
 
 TEST_F(HostResolverImplDnsTest, ServeFromHosts) {
   // Initially, use empty HOSTS file.
   DnsConfig config = CreateValidDnsConfig();
   ChangeDnsConfig(config);
 
-  proc_->AddRuleForAllFamilies("", "");  // Default to failures.
+  proc_->AddRuleForAllFamilies(std::string(),
+                               std::string());  // Default to failures.
   proc_->SignalMultiple(1u);  // For the first request which misses.
 
   Request* req0 = CreateRequest("er_ipv4", 80);
   EXPECT_EQ(ERR_IO_PENDING, req0->Resolve());
   EXPECT_EQ(ERR_NAME_NOT_RESOLVED, req0->WaitForResult());
 
   IPAddressNumber local_ipv4, local_ipv6;
   ASSERT_TRUE(ParseIPLiteralToNumber("127.0.0.1", &local_ipv4));
   ASSERT_TRUE(ParseIPLiteralToNumber("::1", &local_ipv6));
 
@@ skipping 31 matching lines @@
 
   // Request with upper case.
   Request* req6 = CreateRequest("er_IPV4", 80);
   EXPECT_EQ(OK, req6->Resolve());
   EXPECT_TRUE(req6->HasOneAddress("127.0.0.1", 80));
 }
 
 TEST_F(HostResolverImplDnsTest, BypassDnsTask) {
   ChangeDnsConfig(CreateValidDnsConfig());
 
-  proc_->AddRuleForAllFamilies("", "");  // Default to failures.
+  proc_->AddRuleForAllFamilies(std::string(),
+                               std::string());  // Default to failures.
 
   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok.local", 80)->Resolve());
   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok.local.", 80)->Resolve());
   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("oklocal", 80)->Resolve());
   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("oklocal.", 80)->Resolve());
   EXPECT_EQ(ERR_IO_PENDING, CreateRequest("ok", 80)->Resolve());
 
   proc_->SignalMultiple(requests_.size());
 
   for (size_t i = 0; i < 2; ++i)
     EXPECT_EQ(ERR_NAME_NOT_RESOLVED, requests_[i]->WaitForResult()) << i;
 
   for (size_t i = 2; i < requests_.size(); ++i)
     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
 }
 
 TEST_F(HostResolverImplDnsTest, DisableDnsClientOnPersistentFailure) {
   ChangeDnsConfig(CreateValidDnsConfig());
 
-  proc_->AddRuleForAllFamilies("", "");  // Default to failures.
+  proc_->AddRuleForAllFamilies(std::string(),
+                               std::string());  // Default to failures.
 
   // Check that DnsTask works.
   Request* req = CreateRequest("ok_1", 80);
   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
   EXPECT_EQ(OK, req->WaitForResult());
 
   for (unsigned i = 0; i < 20; ++i) {
     // Use custom names to require separate Jobs.
     std::string hostname = base::StringPrintf("err_%u", i);
     // Ensure fallback to ProcTask succeeds.
@@ skipping 33 matching lines @@
                                         : base::StringPrintf("ok_%u", i);
     EXPECT_EQ(ERR_IO_PENDING, CreateRequest(hostname, 80)->Resolve()) << i;
   }
 
   proc_->SignalMultiple(requests_.size());
 
   for (size_t i = 0; i < requests_.size(); ++i)
     EXPECT_EQ(OK, requests_[i]->WaitForResult()) << i;
 
   // Make |proc_| default to failures.
-  proc_->AddRuleForAllFamilies("", "");
+  proc_->AddRuleForAllFamilies(std::string(), std::string());
 
   // DnsTask should still be enabled.
   Request* req = CreateRequest("ok_last", 80);
   EXPECT_EQ(ERR_IO_PENDING, req->Resolve());
   EXPECT_EQ(OK, req->WaitForResult());
 }
 
 }  // namespace net