Island rhythms/gh 13906 handle changing discrim key

lib/cast.js

@@ -68,7 +68,13 @@ module.exports = function cast(schema, obj, options, context) {
         if (val[k] == null || typeof val[k] !== 'object') {
           throw new CastError('Object', val[k], path + '.' + k);
         }
-        val[k] = cast(schema, val[k], options, context);
+        const discriminatorValue = val[k][schema.options.discriminatorKey];
+        if (discriminatorValue == null) {
+          val[k] = cast(schema, val[k], options, context);
+        } else {
+          const discriminatorSchema = getSchemaDiscriminatorByValue(context.schema, discriminatorValue);
+          val[k] = cast(discriminatorSchema ? discriminatorSchema : schema, val[k], options, context);
+        }
       }
     } else if (path === '$where') {
       type = typeof val;
@@ -303,7 +309,6 @@ module.exports = function cast(schema, obj, options, context) {
         } else {
           const ks = Object.keys(val);
           let $cond;
-
           let k = ks.length;
 
           while (k--) {

lib/query.js

@@ -4889,7 +4889,6 @@ function _getPopulatedPaths(list, arr, prefix) {
 
 Query.prototype.cast = function(model, obj) {
   obj || (obj = this._conditions);
-
   model = model || this.model;
   const discriminatorKey = model.schema.options.discriminatorKey;
   if (obj != null &&

lib/schematype.js

@@ -1215,7 +1215,6 @@ SchemaType.prototype.applySetters = function(value, scope, init, priorVal, optio
   if (v == null) {
     return this._castNullish(v);
   }
-
   // do not cast until all setters are applied #665
   v = this.cast(v, scope, init, priorVal, options);
 

test/model.discriminator.test.js

@@ -2180,4 +2180,34 @@ describe('model', function() {
     assert.ok(innerBuildingsPath.schemaOptions.type.discriminators.Garage);
     assert.equal(innerBuildingsPath.schemaOptions.type.discriminators.Garage.discriminatorMapping.value, 'G');
   });
+  it('should not fail when using a discriminator key multiple times (gh-13906)', async function() {
+    const options = { discriminatorKey: 'type' };
+    const eventSchema = new Schema({ date: Schema.Types.Date }, options);
+    const Event = db.model('gh-13906-event', eventSchema);
+
+
+    const clickedLinkEventSchema = new Schema({ url: String }, options);
+    const ClickedLinkEvent = Event.discriminator('ClickedLinkEvent', clickedLinkEventSchema, 'clickedLinkEvent');
+
+
+    const clickedImageEventSchema = new Schema({ image: String }, options);
+    const ClickedImageEvent = Event.discriminator('ClickedImageEvent', clickedImageEventSchema, 'clickedImageEvent');
+
+    const clickedLinkEvent = new ClickedLinkEvent({ url: 'https://clicked-link.com' });
+    assert.equal(clickedLinkEvent.type, 'clickedLinkEvent');
+    assert.equal(clickedLinkEvent.url, 'https://clicked-link.com');
+
+    const clickedImageEvent = new ClickedImageEvent({ image: 'clicked-image.png' });
+    assert.equal(clickedImageEvent.type, 'clickedImageEvent');
+    assert.equal(clickedImageEvent.image, 'clicked-image.png');
+    const query = {
+      type: 'clickedLinkEvent',
+      $or: [
+        { type: 'clickedImageEvent' }
+      ]
+    };
+    const result = await Event.find(query).exec();
+    assert(result);
+
+  });
 });

test/types/models.test.ts

@@ -93,7 +93,7 @@ function gh13930() {
 
   const Test = connection.model<ITest>('Test', TestSchema);
 
-  Test.insertMany<{foo: string}>([{ foo: 'bar' }], { });
+  Test.insertMany<{ foo: string }>([{ foo: 'bar' }], { });
 }
 
 function gh10074() {