Remove direct mongo access from Schema.spec.js.

spec/Schema.spec.js

@@ -1,3 +1,5 @@
+'use strict';
+
 var Config = require('../src/Config');
 var Schema = require('../src/Schema');
 var dd = require('deep-diff');
@@ -512,24 +514,31 @@ describe('Schema', () => {
   it('drops related collection when deleting relation field', done => {
     var obj1 = hasAllPODobject();
     obj1.save()
-    .then(savedObj1 => {
-      var obj2 = new Parse.Object('HasPointersAndRelations');
-      obj2.set('aPointer', savedObj1);
-      var relation = obj2.relation('aRelation');
-      relation.add(obj1);
-      return obj2.save();
-    })
-    .then(() => {
-      config.database.adapter.database.collection('test__Join:aRelation:HasPointersAndRelations', { strict: true }, (err, coll) => {
-        expect(err).toEqual(null);
-        config.database.loadSchema()
-        .then(schema => schema.deleteField('aRelation', 'HasPointersAndRelations', config.database))
-        .then(() => config.database.adapter.database.collection('test__Join:aRelation:HasPointersAndRelations', { strict: true }, (err, coll) => {
-          expect(err).not.toEqual(null);
-          done();
-        }));
+      .then(savedObj1 => {
+        var obj2 = new Parse.Object('HasPointersAndRelations');
+        obj2.set('aPointer', savedObj1);
+        var relation = obj2.relation('aRelation');
+        relation.add(obj1);
+        return obj2.save();
+      })
+      .then(() => config.database.collectionExists('_Join:aRelation:HasPointersAndRelations'))
+      .then(exists => {
+        if (!exists) {
+          fail('Relation collection should exist after save.');
+        }
+      })
+      .then(() => config.database.loadSchema())
+      .then(schema => schema.deleteField('aRelation', 'HasPointersAndRelations', config.database))
+      .then(() => config.database.collectionExists('_Join:aRelation:HasPointersAndRelations'))
+      .then(exists => {
+        if (exists) {
+          fail('Relation collection should not exist after deleting relation field.');
+        }
+        done();
+      }, error => {
+        fail(error);
+        done();
       });
-    })
   });
 
   it('can delete string fields and resave as number field', done => {

src/Adapters/Storage/Mongo/MongoStorageAdapter.js

@@ -30,8 +30,12 @@ export class MongoStorageAdapter {
     });
   }
 
-  dropCollection(name: string) {
-    return this.connect.then(() => this.collection(name).then(collection => collection.drop()));
+  collectionExists(name: string) {
+    return this.connect().then(() => {
+      return this.database.listCollections({ name: name }).toArray();
+    }).then(collections => {
+      return collections.length > 0;
+    });
   }
 
   dropCollection(name: string) {

src/Controllers/DatabaseController.js

@@ -38,6 +38,10 @@ DatabaseController.prototype.collection = function(className) {
   return this.rawCollection(className);
 };
 
+DatabaseController.prototype.collectionExists = function(className) {
+  return this.adapter.collectionExists(this.collectionPrefix + className);
+};
+
 DatabaseController.prototype.rawCollection = function(className) {
   return this.adapter.collection(this.collectionPrefix + className);
 };