Fixes silent header duplication that occurs upon successful revalidation when duplicate headers are present

proxy/http/HttpTransact.cc

@@ -5042,11 +5042,17 @@ HttpTransact::merge_response_header_with_cached_header(HTTPHdr *cached_header, H
     //
     if (field.m_next_dup) {
       if (dups_seen == false) {
+        const char *name2;
+        int name_len2;
+
         // use a second iterator to delete the
         // remaining response headers in the cached response,
         // so that they will be added in the next iterations.
         for (auto spot2 = spot; spot2 != limit; ++spot2) {
-          cached_header->field_delete(&*spot2, true);
+          MIMEField &field2{*spot2};
+          name2 = field2.name_get(&name_len2);
+
+          cached_header->field_delete(name2, name_len2);
         }
         dups_seen = true;
       }

proxy/http/Makefile.am

@@ -86,7 +86,7 @@ if BUILD_TESTS
 libhttp_a_SOURCES += RegressionHttpTransact.cc
 endif
 
-check_PROGRAMS = test_proxy_http test_PreWarm
+check_PROGRAMS = test_proxy_http test_PreWarm test_HttpTransact
 
 TESTS = $(check_PROGRAMS)
 
@@ -122,6 +122,33 @@ test_PreWarm_LDADD = \
 test_PreWarm_SOURCES = \
 	unit_tests/test_PreWarm.cc
 
+test_HttpTransact_CPPFLAGS = \
+	$(AM_CPPFLAGS) \
+	-I$(abs_top_srcdir)/tests/include
+
+if OS_LINUX
+test_HttpTransact_LDFLAGS = $(AM_LDFLAGS)\
+	-Wl,--unresolved-symbols=ignore-all
+else
+test_HttpTransact_LDFLAGS = $(AM_LDFLAGS)\
+    -Wl,-undefined -Wl,suppress -Wl,-flat_namespace -Wl,-dead_strip
+endif
+
+test_HttpTransact_LDADD = \
+	$(top_builddir)/src/tscore/libtscore.la \
+	$(top_builddir)/src/records/librecords_p.a \
+	$(top_builddir)/proxy/ProxySession.o \
+	$(top_builddir)/proxy/http/HttpTransact.o \
+	$(top_builddir)/proxy/http/HttpTransactHeaders.o \
+	$(top_builddir)/proxy/hdrs/libhdrs.a \
+	$(top_builddir)/iocore/eventsystem/libinkevent.a \
+	@SWOC_LIBS@
+
+test_HttpTransact_SOURCES = \
+	../../iocore/cache/test/stub.cc \
+	unit_tests/main.cc \
+	unit_tests/test_HttpTransact.cc
+
 clang-tidy-local: $(libhttp_a_SOURCES) $(noinst_HEADERS)
 	$(CXX_Clang_Tidy)
 

proxy/http/unit_tests/main.cc

@@ -0,0 +1,60 @@
+/** @file
+
+    The main file for tests
+
+    @section license License
+
+    Licensed to the Apache Software Foundation (ASF) under one
+    or more contributor license agreements.  See the NOTICE file
+    distributed with this work for additional information
+    regarding copyright ownership.  The ASF licenses this file
+    to you under the Apache License, Version 2.0 (the
+    "License"); you may not use this file except in compliance
+    with the License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+    Unless required by applicable law or agreed to in writing, software
+    distributed under the License is distributed on an "AS IS" BASIS,
+    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+    See the License for the specific language governing permissions and
+    limitations under the License.
+*/
+
+#define CATCH_CONFIG_MAIN
+#include "catch.hpp"
+
+#include "tscore/I_Layout.h"
+
+#include "I_EventSystem.h"
+#include "records/I_RecordsConfig.h"
+
+#include "diags.i"
+
+#define TEST_THREADS 1
+
+struct EventProcessorListener : Catch::TestEventListenerBase {
+  using TestEventListenerBase::TestEventListenerBase;
+
+  void
+  testRunStarting(Catch::TestRunInfo const & /* testRunInfo */) override
+  {
+    Layout::create();
+    init_diags("", nullptr);
+    RecProcessInit();
+    LibRecordsConfigInit();
+
+    ink_event_system_init(EVENT_SYSTEM_MODULE_PUBLIC_VERSION);
+    eventProcessor.start(TEST_THREADS);
+
+    EThread *main_thread = new EThread;
+    main_thread->set_specific();
+  }
+
+  void
+  testRunEnded(Catch::TestRunStats const & /* testRunStats */) override
+  {
+  }
+};
+
+CATCH_REGISTER_LISTENER(EventProcessorListener);