1 files changed, 37 insertions, 0 deletions
diff --git a/jstests/noPassthroughWithMongod/coll_mod_takes_collection_x_lock.js b/jstests/noPassthroughWithMongod/coll_mod_takes_collection_x_lock.js
new file mode 100644
index 00000000000..46b055209db
--- /dev/null
+++ b/jstests/noPassthroughWithMongod/coll_mod_takes_collection_x_lock.js
@@ -0,0 +1,37 @@
+/**
+ * Ensures that the 'collMod' command takes a Collection MODE_X lock during a no-op.
+ */
+(function() {
+'use strict';
+
+// Note: failpoint name may not be changed due to backwards compatibility problem in
+// multiversion suites running JS tests using the failpoint.
+// In reality this hangs after acquiring a collection MODE_X lock (w/ database MODE_IX)."
+const failpoint = 'hangAfterDatabaseLock';
+assert.commandWorked(db.adminCommand({configureFailPoint: failpoint, mode: "alwaysOn"}));
+
+const conn = db.getMongo();
+assert.commandWorked(db.createCollection('foo'));
+
+// Run a no-op collMod command.
+const awaitParallelShell = startParallelShell(() => {
+    assert.commandWorked(db.runCommand({collMod: 'foo'}));
+}, conn.port);
+
+// Check that the Collection MODE_X lock is being held by checking in lockInfo.
+assert.soon(() => {
+    let lockInfo = assert.commandWorked(db.adminCommand({lockInfo: 1})).lockInfo;
+    for (let i = 0; i < lockInfo.length; i++) {
+        let resourceId = lockInfo[i].resourceId;
+        const mode = lockInfo[i].granted[0].mode;
+        if (resourceId.includes("Collection") && resourceId.includes("test.foo") && mode === "X") {
+            return true;
+        }
+    }
+
+    return false;
+});
+
+assert.commandWorked(db.adminCommand({configureFailPoint: failpoint, mode: "off"}));
+awaitParallelShell();
+})();