Fix loopbackio#1795 - Count issue with related models using though model

Author: regevbr

test/relations.test.js

@@ -605,6 +605,34 @@ describe('relations', function() {
       db.automigrate(['Physician', 'Patient', 'Appointment', 'Address'], done);
     });
 
+    it('should count scoped record with promises based on related model properties', function(done) {
+      let id;
+      Physician.create()
+        .then(function(physician) {
+          return physician.patients.create({name: 'a'})
+            .then(function(ch) {
+              id = ch.id;
+              return physician.patients.create({name: 'z'});
+            })
+            .then(function() {
+              return physician.patients.create({name: 'c'});
+            })
+            .then(function() {
+              return verify(physician);
+            });
+        }).catch(done);
+
+      function verify(physician) {
+        return physician.patients.count({
+          name: 'a',
+        }, function(err, count) {
+          if (err) return done(err);
+          count.should.equal(1);
+          done();
+        });
+      }
+    });
+
     it('should build record on scope', function(done) {
       Physician.create(function(err, physician) {
         const patient = physician.patients.build();