test(query): repro #5775

test/model.discriminator.test.js

@@ -2,13 +2,13 @@
  * Test dependencies.
  */
 
-var start = require('./common'),
-    mongoose = start.mongoose,
-    Schema = mongoose.Schema,
-    assert = require('power-assert'),
-    util = require('util'),
-    clone = require('../lib/utils').clone,
-    random = require('../lib/utils').random;
+var start = require('./common');
+var mongoose = start.mongoose;
+var Schema = mongoose.Schema;
+var assert = require('power-assert');
+var util = require('util');
+var clone = require('../lib/utils').clone;
+var random = require('../lib/utils').random;
 
 /**
  * Setup
@@ -591,6 +591,36 @@ describe('model', function() {
         done();
       });
 
+      it('nested discriminator key with projecting in parent (gh-5775)', function(done) {
+        var itemSchema = new Schema({
+          type: { type: String },
+          active: { type: Boolean, default: true }
+        }, { discriminatorKey: 'type' });
+
+        var collectionSchema = new Schema({
+          items: [itemSchema]
+        });
+
+        var s = new Schema({ count: Number });
+        collectionSchema.path('items').discriminator('type1', s);
+
+        var MyModel = db.model('Collection', collectionSchema);
+        var doc = {
+          items: [{ type: 'type1', active: false, count: 3 }]
+        };
+        MyModel.create(doc, function(error) {
+          assert.ifError(error);
+          MyModel.findOne({}).select('items').exec(function(error, doc) {
+            assert.ifError(error);
+            assert.equal(doc.items.length, 1);
+            assert.equal(doc.items[0].type, 'type1');
+            assert.strictEqual(doc.items[0].active, false);
+            assert.strictEqual(doc.items[0].count, 3);
+            done();
+          });
+        });
+      });
+
       it('embedded discriminators with $push (gh-5009)', function(done) {
         var eventSchema = new Schema({ message: String },
           { discriminatorKey: 'kind', _id: false });