1 files changed, 7 insertions, 16 deletions

diff --git a/src/mongo/db/pipeline/window_function/partition_iterator.cpp b/src/mongo/db/pipeline/window_function/partition_iterator.cpp
index 83925b862b3..d8992aec28c 100644
--- a/src/mongo/db/pipeline/window_function/partition_iterator.cpp
+++ b/src/mongo/db/pipeline/window_function/partition_iterator.cpp
@@ -116,8 +116,8 @@ optional<Document> PartitionIterator::operator[](int index) {
     for (int i = _cache->getHighestIndex(); i < docDesired; i++) {
         // Pull in document from prior stage.
         getNextDocument();
-        // Check whether the next document is available.
-        if (isPaused() || _state == IteratorState::kAwaitingAdvanceToNext ||
+        // Check for EOF or the next partition.
+        if (_state == IteratorState::kAwaitingAdvanceToNext ||
             _state == IteratorState::kAwaitingAdvanceToEOF) {
             return boost::none;
         }
@@ -163,7 +163,6 @@ PartitionIterator::AdvanceResult PartitionIterator::advanceInternal() {
     // whether to pull from the prior stage.
     switch (_state) {
         case IteratorState::kNotInitialized:
-        case IteratorState::kPauseExecution:
         case IteratorState::kIntraPartition:
             // Pull in the next document and advance the pointer.
             getNextDocument();
@@ -302,13 +301,8 @@ optional<std::pair<int, int>> PartitionIterator::getEndpointsRangeBased(
                 for (int i = start; (doc = (*this)[i]); ++i) {
                     Value v = (*_sortExpr)->evaluate(*doc, &_expCtx->variables);
                     if (!lessThan(v, threshold)) {
-                        // This is the first doc we've scanned that crossed the threshold,
-                        // so it's the first doc in the window (as long as it's the expected type).
-                        if (hasExpectedType(v)) {
-                            return i;
-                        } else {
-                            return boost::none;
-                        }
+                        // This is the first doc we've scanned that crossed the threshold.
+                        return i;
                     }
                 }
                 // We scanned every document in the partition, and none crossed the
@@ -473,20 +467,17 @@ void PartitionIterator::getNextDocument() {
         return;
     }
 
-    if (getNextRes.isPaused()) {
-        _state = IteratorState::kPauseExecution;
+    if (!getNextRes.isAdvanced())
         return;
-    }
 
-    tassert(7169100, "getNextResult must have advanced", getNextRes.isAdvanced());
     auto doc = getNextRes.releaseDocument();
 
     // Greedily populate the internal document cache to enable easier memory tracking versus
     // detecting the changing document size during execution of each function.
-    doc = doc.shred();
+    doc.fillCache();
 
     if (_partitionExpr) {
-        if (!_partitionComparator) {
+        if (_state == IteratorState::kNotInitialized) {
             _partitionComparator =
                 std::make_unique<PartitionKeyComparator>(_expCtx, *_partitionExpr, doc);
             _nextPartitionDoc = std::move(doc);