From 8ac600696b51fbeca4eb89834d13e9b3ab08b304 Mon Sep 17 00:00:00 2001
From: Antonio Davi Macedo Coelho de Castro <adavimacedo@gmail.com>
Date: Tue, 10 Sep 2019 16:07:30 -0700
Subject: [PATCH 1/2] Fix: aggregate not matching null values

---
 spec/ParseQuery.Aggregate.spec.js             | 46 +++++++++++++++++++
 .../Storage/Mongo/MongoStorageAdapter.js      |  4 +-
 2 files changed, 49 insertions(+), 1 deletion(-)

diff --git a/spec/ParseQuery.Aggregate.spec.js b/spec/ParseQuery.Aggregate.spec.js
index 10552175a8..f259957e88 100644
--- a/spec/ParseQuery.Aggregate.spec.js
+++ b/spec/ParseQuery.Aggregate.spec.js
@@ -941,6 +941,52 @@ describe('Parse.Query Aggregate testing', () => {
       });
   });
 
+  it('match null values', async () => {
+    const obj1 = new Parse.Object('MyCollection');
+    obj1.set('language', 'en');
+    obj1.set('otherField', 1);
+    const obj2 = new Parse.Object('MyCollection');
+    obj2.set('language', 'en');
+    obj2.set('otherField', 2);
+    const obj3 = new Parse.Object('MyCollection');
+    obj3.set('language', null);
+    obj3.set('otherField', 3);
+    const obj4 = new Parse.Object('MyCollection');
+    obj4.set('language', null);
+    obj4.set('otherField', 4);
+    const obj5 = new Parse.Object('MyCollection');
+    obj5.set('language', 'pt');
+    obj5.set('otherField', 5);
+    const obj6 = new Parse.Object('MyCollection');
+    obj6.set('language', 'pt');
+    obj6.set('otherField', 6);
+    await Parse.Object.saveAll([obj1, obj2, obj3, obj4, obj5, obj6]);
+
+    expect(
+      (await new Parse.Query('MyCollection').aggregate([
+        {
+          match: {
+            language: { $in: [null, 'en'] },
+          },
+        },
+      ]))
+        .map(value => value.otherField)
+        .sort()
+    ).toEqual([1, 2, 3, 4]);
+
+    expect(
+      (await new Parse.Query('MyCollection').aggregate([
+        {
+          match: {
+            $or: [{ language: 'en' }, { language: null }],
+          },
+        },
+      ]))
+        .map(value => value.otherField)
+        .sort()
+    ).toEqual([1, 2, 3, 4]);
+  });
+
   it('project query', done => {
     const options = Object.assign({}, masterKeyOptions, {
       body: {
diff --git a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
index e79bec269b..ee3fd5bd81 100644
--- a/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
+++ b/src/Adapters/Storage/Mongo/MongoStorageAdapter.js
@@ -841,7 +841,9 @@ export class MongoStorageAdapter implements StorageAdapter {
   // As much as I hate recursion...this seemed like a good fit for it. We're essentially traversing
   // down a tree to find a "leaf node" and checking to see if it needs to be converted.
   _parseAggregateArgs(schema: any, pipeline: any): any {
-    if (Array.isArray(pipeline)) {
+    if (pipeline === null) {
+      return null;
+    } else if (Array.isArray(pipeline)) {
       return pipeline.map(value => this._parseAggregateArgs(schema, value));
     } else if (typeof pipeline === 'object') {
       const returnValue = {};

From a79b34b7845e20cb488c577194b33aeacac581e4 Mon Sep 17 00:00:00 2001
From: Antonio Davi Macedo Coelho de Castro <adavimacedo@gmail.com>
Date: Tue, 10 Sep 2019 21:04:58 -0700
Subject: [PATCH 2/2] Exclude Postgres from this new test - it does not even
 support  and  is not working correctly - should be addressed separately

---
 spec/ParseQuery.Aggregate.spec.js | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/spec/ParseQuery.Aggregate.spec.js b/spec/ParseQuery.Aggregate.spec.js
index f259957e88..56b61035dc 100644
--- a/spec/ParseQuery.Aggregate.spec.js
+++ b/spec/ParseQuery.Aggregate.spec.js
@@ -941,7 +941,7 @@ describe('Parse.Query Aggregate testing', () => {
       });
   });
 
-  it('match null values', async () => {
+  it_exclude_dbs(['postgres'])('match null values', async () => {
     const obj1 = new Parse.Object('MyCollection');
     obj1.set('language', 'en');
     obj1.set('otherField', 1);