1 files changed, 24 insertions, 2 deletions
diff --git a/src/mongo/db/pipeline/document_source_union_with.cpp b/src/mongo/db/pipeline/document_source_union_with.cpp
index 67c9fe032e3..a6a31657dbf 100644
--- a/src/mongo/db/pipeline/document_source_union_with.cpp
+++ b/src/mongo/db/pipeline/document_source_union_with.cpp
@@ -30,6 +30,8 @@
 
 #include "mongo/platform/basic.h"
 
+#include <iterator>
+
 #include "mongo/db/pipeline/document_source_union_with.h"
 #include "mongo/db/pipeline/document_source_union_with_gen.h"
 #include "mongo/util/log.h"
@@ -40,6 +42,26 @@ REGISTER_TEST_DOCUMENT_SOURCE(unionWith,
                               DocumentSourceUnionWith::LiteParsed::parse,
                               DocumentSourceUnionWith::createFromBson);
 
+namespace {
+std::unique_ptr<Pipeline, PipelineDeleter> buildPipelineFromViewDefinition(
+    const boost::intrusive_ptr<ExpressionContext>& expCtx,
+    ExpressionContext::ResolvedNamespace resolvedNs,
+    std::vector<BSONObj> currentPipeline) {
+    if (resolvedNs.pipeline.empty()) {
+        return uassertStatusOK(Pipeline::parse(currentPipeline, expCtx->copyWith(resolvedNs.ns)));
+    }
+    auto resolvedPipeline = std::move(resolvedNs.pipeline);
+    resolvedPipeline.reserve(currentPipeline.size() + resolvedPipeline.size());
+    resolvedPipeline.insert(resolvedPipeline.end(),
+                            std::make_move_iterator(currentPipeline.begin()),
+                            std::make_move_iterator(currentPipeline.end()));
+
+    return uassertStatusOK(
+        Pipeline::parse(std::move(resolvedPipeline), expCtx->copyWith(resolvedNs.ns)));
+}
+
+}  // namespace
+
 std::unique_ptr<DocumentSourceUnionWith::LiteParsed> DocumentSourceUnionWith::LiteParsed::parse(
     const NamespaceString& nss, const BSONElement& spec) {
     uassert(ErrorCodes::FailedToParse,
@@ -112,8 +134,8 @@ boost::intrusive_ptr<DocumentSource> DocumentSourceUnionWith::createFromBson(
     }
     return make_intrusive<DocumentSourceUnionWith>(
         expCtx,
-        uassertStatusOK(
-            Pipeline::parse(std::move(pipeline), expCtx->copyWith(std::move(unionNss)))));
+        buildPipelineFromViewDefinition(
+            expCtx, expCtx->getResolvedNamespace(std::move(unionNss)), std::move(pipeline)));
 }
 
 DocumentSource::GetNextResult DocumentSourceUnionWith::doGetNext() {