SERVER-26462 Check if _buffer is allocated in DocumentStorage::clone()

1 files changed, 29 insertions, 0 deletions

diff --git a/jstests/aggregation/bugs/server26462.js b/jstests/aggregation/bugs/server26462.js
new file mode 100644
index 00000000000..b0ef33ae35b
--- /dev/null
+++ b/jstests/aggregation/bugs/server26462.js
@@ -0,0 +1,29 @@
+// Tests that adding a field that only contains metadata does not cause a segmentation fault when
+// grouping on the added field.
+(function() {
+    "use strict";
+
+    // Drop the old test collection, if any.
+    db.server26462.drop();
+
+    // Insert some test documents into the collection.
+    assert.writeOK(db.server26462.insert({"_id": 1, "title": "cakes and ale"}));
+    assert.writeOK(db.server26462.insert({"_id": 2, "title": "more cakes"}));
+    assert.writeOK(db.server26462.insert({"_id": 3, "title": "bread"}));
+    assert.writeOK(db.server26462.insert({"_id": 4, "title": "some cakes"}));
+
+    // Create a text index on the documents.
+    assert.commandWorked(db.server26462.createIndex({title: "text"}));
+
+    // Add a metadata only field in the aggregation pipeline and use that field in the $group _id.
+    let res = db.server26462
+                  .aggregate([
+                      {$match: {$text: {$search: "cake"}}},
+                      {$addFields: {fooScore: {$meta: "textScore"}}},
+                      {$group: {_id: "$fooScore", count: {$sum: 1}}}
+                  ])
+                  .itcount();
+
+    // Assert that the command worked.
+    assert.eq(2, res);
+})();