refactor!: CreateIndexOp returns string, CreateIndexesOp returns array

src/operations/indexes.ts

@@ -153,24 +153,23 @@ export class IndexesOperation extends AbstractOperation<Document> {
 export class CreateIndexesOperation extends CommandOperation<Document> {
   options: CreateIndexesOptions;
   collectionName: string;
-  onlyReturnNameOfCreatedIndex?: boolean;
+  singular?: boolean;
   indexes: IndexDescription[];
 
   constructor(
     parent: OperationParent,
     collectionName: string,
     indexes: IndexDescription[],
-    options?: CreateIndexesOptions
+    options?: CreateIndexesOptions,
+    singular?: boolean
   ) {
     super(parent, options);
 
     this.options = options ?? {};
+    this.singular = singular ?? false;
     this.collectionName = collectionName;
 
     this.indexes = indexes;
-    if (indexes.length === 1) {
-      this.onlyReturnNameOfCreatedIndex = true;
-    }
   }
 
   execute(server: Server, session: ClientSession, callback: Callback<Document>): void {
@@ -219,13 +218,14 @@ export class CreateIndexesOperation extends CommandOperation<Document> {
     // collation is set on each index, it should not be defined at the root
     this.options.collation = undefined;
 
-    super.executeCommand(server, session, cmd, (err, result) => {
+    super.executeCommand(server, session, cmd, err => {
       if (err) {
         callback(err);
         return;
       }
 
-      callback(undefined, this.onlyReturnNameOfCreatedIndex ? indexes[0].name : result);
+      const names = indexes.map(index => index.name);
+      callback(undefined, (this.singular ? names[0] : names) as Document);
     });
   }
 }
@@ -244,7 +244,7 @@ export class CreateIndexOperation extends CreateIndexesOperation {
     //   coll.createIndex([['a', 1]]);
     // createIndexes is always called with an array of index spec objects
 
-    super(parent, collectionName, [makeIndexSpec(indexSpec, options)], options);
+    super(parent, collectionName, [makeIndexSpec(indexSpec, options)], options, true);
   }
 }
 

test/functional/index.test.js

@@ -831,10 +831,8 @@ describe('Indexes', function () {
     }
   });
 
-  it('should correctly execute createIndexes', {
-    metadata: {
-      requires: { mongodb: '>=2.6.0', topology: ['single', 'ssl', 'heap', 'wiredtiger'] }
-    },
+  it('should correctly execute createIndexes with multiple indexes', {
+    metadata: { requires: { mongodb: '>=2.6.0', topology: ['single'] } },
 
     test: function (done) {
       var configuration = this.configuration;
@@ -845,7 +843,7 @@ describe('Indexes', function () {
           [{ key: { a: 1 } }, { key: { b: 1 }, name: 'hello1' }],
           function (err, r) {
             expect(err).to.not.exist;
-            test.equal(3, r.numIndexesAfter);
+            expect(r).to.deep.equal(['a_1', 'hello1']);
 
             db.collection('createIndexes')
               .listIndexes()
@@ -868,6 +866,38 @@ describe('Indexes', function () {
     }
   });
 
+  it('should correctly execute createIndexes with one index', {
+    metadata: { requires: { mongodb: '>=2.6.0', topology: ['single'] } },
+
+    test: function (done) {
+      var configuration = this.configuration;
+      var client = configuration.newClient(configuration.writeConcernMax(), { maxPoolSize: 1 });
+      client.connect(function (err, client) {
+        var db = client.db(configuration.db);
+        db.collection('createIndexes').createIndexes([{ key: { a: 1 } }], function (err, r) {
+          expect(err).to.not.exist;
+          expect(r).to.deep.equal(['a_1']);
+
+          db.collection('createIndexes')
+            .listIndexes()
+            .toArray(function (err, docs) {
+              expect(err).to.not.exist;
+              var keys = {};
+
+              for (var i = 0; i < docs.length; i++) {
+                keys[docs[i].name] = true;
+              }
+
+              test.ok(keys['a_1']);
+              test.ok(keys['hello1']);
+
+              client.close(done);
+            });
+        });
+      });
+    }
+  });
+
   it('shouldCorrectlyCreateTextIndex', {
     metadata: {
       requires: { topology: ['single', 'replicaset', 'sharded', 'ssl', 'heap', 'wiredtiger'] }