1 files changed, 63 insertions, 0 deletions
diff --git a/jstests/noPassthrough/ttl_monitor_does_not_unregister_index_during_collection_creation.js b/jstests/noPassthrough/ttl_monitor_does_not_unregister_index_during_collection_creation.js
new file mode 100644
index 00000000000..fd1f45902bf
--- /dev/null
+++ b/jstests/noPassthrough/ttl_monitor_does_not_unregister_index_during_collection_creation.js
@@ -0,0 +1,63 @@
+/**
+ * Ensures that the TTLMonitor does not remove the cached index information from the
+ * TTLCollectionCache object for a newly created index before the implicitly created collection is
+ * registered and visible in the CollectionCatalog.
+ * Removing this cached index information prevents the TTLMonitor from removing expired documents
+ * for that collection.
+ */
+(function() {
+'use strict';
+
+const conn = MongoRunner.runMongod({setParameter: 'ttlMonitorSleepSecs=1'});
+
+const dbName = "test";
+const collName = "ttlMonitor";
+
+const db = conn.getDB(dbName);
+const coll = db.getCollection(collName);
+
+TestData.dbName = dbName;
+TestData.collName = collName;
+
+coll.drop();
+
+const failPoint = "hangTTLCollectionCacheAfterRegisteringInfo";
+assert.commandWorked(db.adminCommand({configureFailPoint: failPoint, mode: "alwaysOn"}));
+
+// Create an index on a non-existent collection. This will implicitly create the collection.
+let awaitEnsureIndex = startParallelShell(() => {
+    const testDB = db.getSiblingDB(TestData.dbName);
+    assert.commandWorked(
+        testDB.getCollection(TestData.collName).ensureIndex({x: 1}, {expireAfterSeconds: 0}));
+}, db.getMongo().port);
+
+// Wait for the TTL monitor to run and register the index in the TTL collection cache.
+checkLog.containsJson(db.getMongo(), 4664000);
+
+// Let the TTL monitor run once. It should not remove the index from the cached TTL information
+// until the collection is committed.
+let ttlPass = assert.commandWorked(db.serverStatus()).metrics.ttl.passes;
+assert.soon(function() {
+    return coll.getDB().serverStatus().metrics.ttl.passes >= ttlPass + 1;
+}, "TTL monitor didn't run.");
+
+// Finish the index build.
+assert.commandWorked(db.adminCommand({configureFailPoint: failPoint, mode: "off"}));
+awaitEnsureIndex();
+
+// Insert documents, which should expire immediately and be removed on the next TTL pass.
+const now = new Date();
+for (let i = 0; i < 10; i++) {
+    assert.commandWorked(coll.insert({x: now}));
+}
+
+// Let the TTL monitor run once to remove the expired documents.
+ttlPass = assert.commandWorked(db.serverStatus()).metrics.ttl.passes;
+assert.soon(function() {
+    return coll.getDB().serverStatus().metrics.ttl.passes >= ttlPass + 1;
+}, "TTL monitor didn't run.");
+
+assert.eq(0, coll.find({}).count());
+
+MongoRunner.stopMongod(conn);
+}());