Issue #2402 - Move code to fill InternalHeaders from an nsIChannel response into utility method. https://bugzilla.mozilla.org/show_bug.cgi?id=1337543

dom/fetch/FetchDriver.cpp

@@ -12,7 +12,6 @@
 #include "nsIOutputStream.h"
 #include "nsIHttpChannel.h"
 #include "nsIHttpChannelInternal.h"
-#include "nsIHttpHeaderVisitor.h"
 #include "nsIScriptSecurityManager.h"
 #include "nsIThreadRetargetableRequest.h"
 #include "nsIUploadChannel2.h"
@@ -449,38 +448,6 @@ FetchDriver::FailWithNetworkError()
   mChannel = nullptr;
 }
 
-namespace {
-class FillResponseHeaders final : public nsIHttpHeaderVisitor {
-  InternalResponse* mResponse;
-
-  ~FillResponseHeaders()
-  { }
-public:
-  NS_DECL_ISUPPORTS
-
-  explicit FillResponseHeaders(InternalResponse* aResponse)
-    : mResponse(aResponse)
-  {
-  }
-
-  NS_IMETHOD
-  VisitHeader(const nsACString & aHeader, const nsACString & aValue) override
-  {
-    ErrorResult result;
-    mResponse->Headers()->Append(aHeader, aValue, result);
-    if (result.Failed()) {
-      NS_WARNING(nsPrintfCString("Fetch ignoring illegal header - '%s': '%s'",
-                                 PromiseFlatCString(aHeader).get(),
-                                 PromiseFlatCString(aValue).get()).get());
-      result.SuppressException();
-    }
-    return NS_OK;
-  }
-};
-
-NS_IMPL_ISUPPORTS(FillResponseHeaders, nsIHttpHeaderVisitor)
-} // namespace
-
 NS_IMETHODIMP
 FetchDriver::OnStartRequest(nsIRequest* aRequest,
                             nsISupports* aContext)
@@ -540,11 +507,7 @@ FetchDriver::OnStartRequest(nsIRequest* aRequest,
     response = new InternalResponse(responseStatus, statusText,
                                     mRequest->GetCredentialsMode());
 
-    RefPtr<FillResponseHeaders> visitor = new FillResponseHeaders(response);
+    response->Headers()->FillResponseHeaders(httpChannel);
-    rv = httpChannel->VisitResponseHeaders(visitor);
-    if (NS_WARN_IF(NS_FAILED(rv))) {
-      NS_WARNING("Failed to visit all headers.");
-    }
 
     // If Content-Encoding or Transfer-Encoding headers are set, then the actual
     // Content-Length (which refer to the decoded data) is obscured behind the encodings.

dom/fetch/InternalHeaders.cpp

@@ -11,6 +11,7 @@
 
 #include "nsCharSeparatedTokenizer.h"
 #include "nsContentUtils.h"
+#include "nsIHttpHeaderVisitor.h"
 #include "nsNetUtil.h"
 #include "nsReadableUtils.h"
 
@@ -478,6 +479,48 @@ InternalHeaders::Fill(const Record<nsCString, nsCString>& aInit, ErrorResult& aR
   }
 }
 
+namespace {
+
+class FillHeaders final : public nsIHttpHeaderVisitor
+{
+  RefPtr<InternalHeaders> mInternalHeaders;
+
+  ~FillHeaders() = default;
+
+public:
+  NS_DECL_ISUPPORTS
+
+  explicit FillHeaders(InternalHeaders* aInternalHeaders)
+    : mInternalHeaders(aInternalHeaders)
+  {
+    MOZ_DIAGNOSTIC_ASSERT(mInternalHeaders);
+  }
+
+  NS_IMETHOD
+  VisitHeader(const nsACString& aHeader, const nsACString& aValue) override
+  {
+    IgnoredErrorResult result;
+    mInternalHeaders->Append(aHeader, aValue, result);
+    return NS_OK;
+  }
+};
+
+NS_IMPL_ISUPPORTS(FillHeaders, nsIHttpHeaderVisitor)
+
+} // namespace
+
+void
+InternalHeaders::FillResponseHeaders(nsIRequest* aRequest)
+{
+  nsCOMPtr<nsIHttpChannel> httpChannel = do_QueryInterface(aRequest);
+  if (!httpChannel) {
+    return;
+  }
+
+  RefPtr<FillHeaders> visitor = new FillHeaders(this);
+  httpChannel->VisitResponseHeaders(visitor);
+}
+
 bool
 InternalHeaders::HasOnlySimpleHeaders() const
 {

dom/fetch/InternalHeaders.h

@@ -114,6 +114,7 @@ public:
   void Fill(const InternalHeaders& aInit, ErrorResult& aRv);
   void Fill(const Sequence<Sequence<nsCString>>& aInit, ErrorResult& aRv);
   void Fill(const Record<nsCString, nsCString>& aInit, ErrorResult& aRv);
+  void FillResponseHeaders(nsIRequest* aRequest);
 
   bool HasOnlySimpleHeaders() const;