Add unittest for r37566 (on PAC failure, should fallback to DIRECT).

To make it more testable, I had to move the fallback code in question from HttpNetworkTransaction to ProxyService.
Although I think this is a better fit for that code anway, so it should be an overall readability improvement.

BUG=32316
TEST=ProxyServiceTest.ProxyFallback_BadConfig, ProxyServiceTest.ProxyResolverFails

Review URL: http://codereview.chromium.org/556087

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@38177 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 23 insertions, 9 deletions

diff --git a/net/proxy/proxy_service.cc b/net/proxy/proxy_service.cc
index fb607ec..90fd297 100644
--- a/net/proxy/proxy_service.cc
+++ b/net/proxy/proxy_service.cc
@@ -492,13 +492,23 @@ int ProxyService::DidFinishResolvingProxy(ProxyInfo* result,
           load_log,
           std::string("Resolved proxy list: ") + result->ToPacString());
     }
+    result->DeprioritizeBadProxies(proxy_retry_info_);
   } else {
+    LoadLog::AddStringLiteral(
+        load_log,
+        "Got an error from proxy resolver, falling-back to DIRECT.");
     LoadLog::AddErrorCode(load_log, result_code);
-  }
 
-  // Clean up the results list.
-  if (result_code == OK)
-    result->DeprioritizeBadProxies(proxy_retry_info_);
+    // Fall-back to direct when the proxy resolver fails. This corresponds
+    // with a javascript runtime error in the PAC script.
+    //
+    // This implicit fall-back to direct matches Firefox 3.5 and
+    // Internet Explorer 8. For more information, see:
+    //
+    // http://www.chromium.org/developers/design-documents/proxy-settings-fallback
+    result->UseDirect();
+    result_code = OK;
+  }
 
   LoadLog::EndEvent(load_log, LoadLog::TYPE_PROXY_SERVICE);
   return result_code;
diff --git a/net/proxy/proxy_service_unittest.cc b/net/proxy/proxy_service_unittest.cc
index 2e57e51..b6804ce 100644
--- a/net/proxy/proxy_service_unittest.cc
+++ b/net/proxy/proxy_service_unittest.cc
@@ -330,7 +330,10 @@ TEST(ProxyServiceTest, ProxyResolverFails) {
   // Fail the first resolve request in MockAsyncProxyResolver.
   resolver->pending_requests()[0]->CompleteNow(ERR_FAILED);
 
-  EXPECT_EQ(ERR_FAILED, callback1.WaitForResult());
+  // Although the proxy resolver failed the request, ProxyService implicitly
+  // falls-back to DIRECT.
+  EXPECT_EQ(OK, callback1.WaitForResult());
+  EXPECT_TRUE(info.is_direct());
 
   // The second resolve request will try to run through the proxy resolver,
   // regardless of whether the first request failed in it.
@@ -642,10 +645,11 @@ TEST(ProxyServiceTest, ProxyFallback_BadConfig) {
   // This simulates a javascript runtime error in the PAC script.
   resolver->pending_requests()[0]->CompleteNow(ERR_FAILED);
 
-  // No proxy servers are returned, since we failed.
-  EXPECT_EQ(ERR_FAILED, callback3.WaitForResult());
-  EXPECT_FALSE(info2.is_direct());
-  EXPECT_TRUE(info2.is_empty());
+  // Although the resolver failed, the ProxyService will implicitly fall-back
+  // to a DIRECT connection.
+  EXPECT_EQ(OK, callback3.WaitForResult());
+  EXPECT_TRUE(info2.is_direct());
+  EXPECT_FALSE(info2.is_empty());
 
   // The PAC script will work properly next time and successfully return a
   // proxy list. Since we have not marked the configuration as bad, it should