1 files changed, 9 insertions, 0 deletions
diff --git a/src/mongo/db/query/sort_pattern.h b/src/mongo/db/query/sort_pattern.h
index 1b55472a79b..bed9b338535 100644
--- a/src/mongo/db/query/sort_pattern.h
+++ b/src/mongo/db/query/sort_pattern.h
@@ -105,10 +105,19 @@ public:
         return _sortPattern[idx];
     }
 
+    /**
+     * Returns true if this SortPattern is an extension of the other.
+     */
+    bool isExtensionOf(const SortPattern& other) const;
+
     bool operator==(const SortPattern& other) const {
         return _sortPattern == other._sortPattern && _paths == other._paths;
     }
 
+    bool operator!=(const SortPattern& other) const {
+        return !(*this == other);
+    }
+
     std::vector<SortPatternPart>::const_iterator begin() const {
         return _sortPattern.cbegin();
     }