SERVER-66622 fail to createCollection when running in 5.x compatibility mode

2 files changed, 48 insertions, 2 deletions

diff --git a/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downgrade.js b/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downgrade.js
index 0808e2be307..670d8afa572 100644
--- a/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downgrade.js
+++ b/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downgrade.js
@@ -44,8 +44,8 @@ function runTest(targetFCV) {
     assert.commandWorked(db.adminCommand({setFeatureCompatibilityVersion: latestFCV}));
 }
 
-targetFCV(lastLTSFCV);
-targetFCV(lastContinuousFCV);
+runTest(lastLTSFCV);
+runTest(lastContinuousFCV);
 
 rst.stopSet();
 }());
\ No newline at end of file
diff --git a/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downlevel_nocreate.js b/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downlevel_nocreate.js
new file mode 100644
index 00000000000..b34933ac7a3
--- /dev/null
+++ b/jstests/multiVersion/targetedTestsLastLtsFeatures/fle2_downlevel_nocreate.js
@@ -0,0 +1,46 @@
+/**
+ * Tests that the cluster cannot be downgraded when encrypted fields present
+ *
+ * @tags: [
+ * requires_fcv_60
+ * ]
+ */
+
+load("jstests/fle2/libs/encrypted_client_util.js");
+
+(function() {
+"use strict";
+
+const rst = new ReplSetTest({nodes: 1});
+rst.startSet();
+rst.initiate();
+rst.awaitReplication();
+
+let dbName = 'downgrade_test';
+let conn = rst.getPrimary();
+let db = conn.getDB("admin");
+let client = new EncryptedClient(conn, dbName);
+let dbTest = db.getSiblingDB('create_encrypted_collection_db');
+
+const sampleEncryptedFields = {
+    "fields": [
+        {
+            "path": "firstName",
+            "keyId": UUID("11d58b8a-0c6c-4d69-a0bd-70c6d9befae9"),
+            "bsonType": "string",
+            "queries": {"queryType": "equality"}  // allow single object or array
+        },
+    ]
+};
+
+assert.commandWorked(db.adminCommand({setFeatureCompatibilityVersion: lastLTSFCV}));
+assert.commandFailedWithCode(
+    dbTest.createCollection("basic2", {encryptedFields: sampleEncryptedFields}),
+    6662201,
+    "Create in 5.0 FCV passed");
+
+assert.commandWorked(db.adminCommand({setFeatureCompatibilityVersion: latestFCV}));
+assert.commandWorked(dbTest.createCollection("basic", {encryptedFields: sampleEncryptedFields}));
+
+rst.stopSet();
+}());