SERVER-37930 Add test coverage for createIndexes inside nested applyOps

jstests/replsets/nested_apply_ops_create_indexes.js

@@ -0,0 +1,62 @@
+/**
+ * Test createIndexes while recursively locked in a nested applyOps.
+ */
+(function() {
+    "use strict";
+
+    let ensureIndexExists = function(testDB, collName, indexName, expectedNumIndexes) {
+        let cmd = {listIndexes: collName};
+        let res = testDB.runCommand(cmd);
+        assert.commandWorked(res, "could not run " + tojson(cmd));
+        let indexes = testDB[collName].getIndexes();
+
+        assert.eq(indexes.length, expectedNumIndexes);
+
+        let foundIndex = indexes.some(index => index.name === indexName);
+        assert(foundIndex,
+               "did not find the index '" + indexName + "' amongst the collection indexes: " +
+                   tojson(indexes));
+    };
+
+    let rst = new ReplSetTest({nodes: 3});
+    rst.startSet();
+    rst.initiate();
+
+    let collName = "col";
+    let dbName = "nested_apply_ops_create_indexes";
+
+    let primaryTestDB = rst.getPrimary().getDB(dbName);
+    let cmd = {"create": collName};
+    let res = primaryTestDB.runCommand(cmd);
+    assert.commandWorked(res, "could not run " + tojson(cmd));
+    rst.awaitReplication();
+
+    let uuid = primaryTestDB.getCollectionInfos()[0].info.uuid;
+    let cmdFormatIndexNameA = "a_1";
+    cmd = {
+        applyOps: [{
+            op: "c",
+            ns: dbName + ".$cmd",
+            ui: uuid,
+            o: {
+                applyOps: [{
+                    op: "c",
+                    ns: dbName + "." + collName,
+                    ui: uuid,
+                    o: {
+                        createIndexes: collName,
+                        v: 2,
+                        key: {a: 1},
+                        name: cmdFormatIndexNameA
+                    }
+                }]
+            }
+        }]
+    };
+    res = primaryTestDB.runCommand(cmd);
+    assert.commandWorked(res, "could not run " + tojson(cmd));
+    rst.awaitReplication();
+    ensureIndexExists(primaryTestDB, collName, cmdFormatIndexNameA, 2);
+
+    rst.stopSet();
+})();